Category Archives: Equipment

The Future of Emcomm

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Here comes Starlink!

I’ve been reading a number of reports from the areas affected by the two major hurricanes (Helene and Milton). The North Carolina experience is particularly interesting because people have experienced the loss of communication and electrical service for several weeks. I can imagine this same thing happening in other parts of the country, including my area. As one example, read the on-the-ground disaster report from Thomas/K4SWL.

There are two important technology disruptions showing up in North Carolina: satellite-based internet (Starlink) and mobile-phone-to-satellite (SMS) text messaging. Starlink is having a significant impact during this incident, while mobile phone satellite messaging is still emerging. Steve N8GNJ has some worthy thoughts on these topics in Zero Retires 173. Although I have served in many ARES/RACES deployments over the years, I don’t consider myself an expert in this area. I’d appreciate comments from Emcomm folks who have spent more time thinking about this.

A typical ham radio emcomm station with multiple radios covering multiple bands.

Types of Emergency Communication

Most relevant emergency comms lump into 1) short-range comms (< 5 miles) between family, friends, and neighbors. 2) medium-range comms (50 miles) to obtain information and resources. 3) long-range comms (beyond 50 miles) to connect with distant family, friends, and resources.

  1. Short-Range Comms: This is the type of communication that is well served by mobile phones, except when the mobile networks are down. This is happening a lot in North Carolina. Lightly licensed VHF/UHF radios such as FRS and GMRS can be used to replace your mobile phone. Think: wanting to call your neighbor 3 miles away to see if they are OK or can provide something you need. (I have a few FRS/GMRS radios in my stash to share with neighbors. See TIDRadio TD-H3) VHF/UHF ham radio is, of course, even better for this, except the parties involved need to be licensed. (OK, you can operate unlicensed in a true emergency, but that has other issues. See The Talisman Radio.)
  2. Medium-Range Comms: This is a great fit for VHF/UHF ham radio using repeaters or highly-capable base stations. GMRS repeaters can also serve this need. These communications will typically be about situational awareness and resource availability in the surrounding area. For example, someone on the local ham repeater may know whether the highway is open to the place you want to drive.
  3. Long-Range Comms: Historically, this has been done by HF ham radio and a lot of emergency traffic is still handled this way. The shift that is happening is that setting up a Starlink earth station feeding a local WiFi network can help a lot of people in a very effective manner.  Compare passing a formal piece of health-and-welfare traffic via ham radio to letting a non-licensed person simply get Wi-Fi access to their email or text messaging app. Hams are doing this, but many unlicensed techie folks have set up these systems and freely shared them with the public.

Mobile Satellite Messaging

Various providers now offer a basic text messaging capability using smartphones talking to satellites. Today, this capability is often limited to emergencies (“SOS”), and it is relatively slow. With time, this capability will certainly improve, and basic satellite texting will become ubiquitous on smartphones. This will be great for checking in with distant friends and families, but it may not be that useful for Short Range and Medium Range comms. Someday, it might include voice comms, but in the near term, it is probably just text-based.

Evan K2EJT provides some useful tips based on his experience here in this video. However, he doesn’t address the Starlink capability.

Summary

While much of the public appreciates the usefulness of ham radio during emergencies, I am already hearing questions like “Doesn’t Starlink cover this need?” My view is that Starlink (and similar commercial sats) is very useful and will play an important emcomm role, but it does not cover all of the communication needs during incidents such as hurricanes, blizzards, wildfires, earthquakes, etc. Similarly, Mobile Satellite communications will be a great help during emergencies in the future but will probably not cover every need. Emcomm folks (ARES and RACES) will need to adapt their approach to take this into account.

Those are my thoughts. What do you think?

73 Bob K0NR

Handie-Talkie or Walkie-Talkie?

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The Motorola HT-220 Handie-Talkie

In ham radio, we often use Handie-Talkie or HT to describe a compact, handheld transceiver. My first exposure to the term Handie-Talkie was when I became a licensed radio amateur in 1977. As a student at Purdue University (W9YB), the absolute coolest VHF radio to have was the Motorola HT-220. Even a used one commanded a high price so they were out of my price range and I never owned one. These were 6-channel crystal-controlled transceivers…back then you had to set up the radio with the particular 2m frequencies you wanted to use. Because it was such an iconic radio, there are many HT-220 enthusiasts still around with websites with tons of useful information. See the HT-220 Page.

Motorola trademarked the name Handie-Talkie and used that nomenclature for many years with its line of portable radios. However, this trademark has expired, so now Handie-Talkie is a generic term.

The First Handie-Talkie

But the HT-220 was not the first Handie-Talkie, so I started poking around to find out how this name originated. Back in World War II, the SCR-536 was a portable “hand-held” transceiver developed in 1940 by Galvin Manufacturing (later Motorola, Inc.)  I put “hand-held” in quotes because, by today’s standards, it was a Hand FULL. But most people consider the SCR-536 to be the first modern, self-contained HT transceiver. The Wikipedia article for the SCR-536 describes the radio quite well. The radio put out about 360 mW of RF power on 3.5 and 6.0 MHz (Oops, I mean 3500 to 6000 kilocycles) using Amplitude Modulation (AM). The circuitry relied on smallish vacuum tubes, creating quite a design challenge. Motorola has a page on its website that talks about the origins of the radio. IEEE Spectrum also published an excellent article: The SCR-536 Handie-Talkie Was the Modern Walkie-Talkie’s Finicky Ancestor. The January 2005 issue of QST has an interesting article by Gil McElroy, VE3PKD, A Short History of the Handheld Transceiver. It provides more history and insight into this fun topic.

The SCR-536 Handie-Talkie

 

 

 

 

 

 

 

 

 

The First Walkie-Talkie

A few years later (1942), a backpack portable radio was introduced, called the SCR-300. I always assumed that the backpack-style radio would have come first and the more compact radio SCR-536 would be later. (Actually, there were previous backpack radios, such as the SCR-194). This new backpack-style radio was referred to as a Walkie-Talkie. According to the manual, the SCR-300 was “primarily intended as a walkie-talkie for foot combat troops”. I suppose the emphasis was on how you can walk and talk, with a radio on your back.

The SCR-300 Walkie-Talkie transceiver.

This article: SCR-300 WW2 Radio Backpack: The “Walkie Talkie” That Shaped the War describes this radio as a game-changer for frontline troops. The radio weighed a heavy 35 pounds, and used Frequency Modulation (FM) on 40 to 48 Megacycles.

Of course, with technology development, there is always the question of “who was first”? The SCR-194 that predated the SCR-300 might be considered the first walkie-talkie. However, the SCR-300 and the SCR-536 seem to get all of the glory, probably due to their impact on the war effort. However, take a look here if you want to dig deeper: TALK the WALK or WALK the TALK: Who actually developed the first Walkie-Talkie?

This article describes the development and use of the SCR-300 and mentions some of the limitations of the SCR-194: SCR-300 History Development Employment and Details Final Draft This is a big file with many photos but worth reading if you have the time.

Today’s Terminology

The Yaesu FT-4X handheld transceiver

Fast forward to today and we see that the HT and Handie-Talkie nomenclature is common in the amateur radio world. The photo to the left shows a modern 2m/70cm HT, the Yaesu FT-4X.

The term “walkie-talkie” has morphed to something quite different and is used generically to describe a handheld radio. This term covers a wide range of radios, from low-cost Family Radio Service (FRS) radios to higher-quality professional radios. This is quite different from the original Walkie-Talkie, a backpack radio weighing 35 pounds.

The military has progressed with improved communication technology, still using backpack-style radios, now referred to as manpack radios. These are amazing radios that pack extensive capability into a relatively small package. The AN/PR-158 shown below covers 30 to 2500 MHz in frequency, satellite comms, advanced encryption, narrowband and wideband modes: AM, ASK, FM, FSK, PSK, CPM, GMSK, and plenty more. This radio weighs 12.7 pounds with the battery installed, so a lot lighter than the old SCR-300.

A modern military manpack radio (AN/PR-158)

So that’s a quick tour through some radio terminology along with a bit of historical perspective. I discovered there is an infinite supply of information out there on the history and technology of military radios. If you want to dig deeper, go for it!

73 Bob K0NR

Common Ham Shack Radio Configurations

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Amateur radio transceivers have improved dramatically over the decades and they pack a lot of capability into relatively compact radios. In this post, we will take a look at the typical configurations and how they may impact setting up a flexible amateur radio station today. This discussion is focused on currently available new gear, with 50 to 100 watts of RF power.

The Kenwood TS-430S was a popular HF transceiver in the 1980s.

The most common HF radio configuration used to be a 5-band model that offered CW, AM, and SSB on 80 meters, 40 meters, 20 meters, 15 meters, and 10 meters. In the early 1980s, the WARC bands were added (named for the World Administrative Radio Conference of 1979) that authorized these new bands. The WARC bands are 30 meters, 17 meters, and 12 meters. These attractive new bands were soon added to the standard HF rig.  Most HF radios include 160 meters (actually a Medium Frequency or MF band) on the low end and a general coverage receiver for 150 kHz to 30 MHz. So these days, the typical HF transceiver handles 9 bands and many different modes. (Actually, most of these rigs now include 6 meters, more on that later.)

Dominant Design

In the world of product development, the concept of a dominant design often emerges. This generally accepted approach dominates a particular market and is considered the standard way of doing things in a particular product category.

From Wikipedia:

Dominant design is a technology management concept introduced by James M. Utterback and William J. Abernathy in 1975, identifying key technological features that become a de facto standard. A dominant design is the one that wins the allegiance of the marketplace, the one to which competitors and innovators must adhere if they hope to command significant market following.

We will see that most ham radio gear conforms to the concept of a dominant design. That is, certain product configurations become standard, especially in terms of frequency bands and modes. Manufacturers still innovate by adding new features in an attempt to differentiate and obtain competitive advantage but the basic capabilities are standard. The dominant design for HF transceivers is the 100-watt radio that covers 160m through 6m.

VHF/UHF Radios

For VHF/UHF, the situation is a bit more scattered. 2-meter FM is the most popular band and back in the olden days, it was common to just have a single-band 2m FM rig in the shack. To cover 70 cm FM, a radio ham needed a second radio but later dual-band radios showed up that covered 2m and 70 cm. Today, the dominant design for VHF/UHF is the dual-band FM transceiver (typically 50 watts of output power) and there are so many of these available I won’t attempt to list them.

The IC-2730A is a basic 2m and 70cm transceiver with dual receivers.

VHF FM is the utility mode for amateur radio and many hams are just fine using FM (or one of the digital voice modes) on VHF/UHF. Those who want to stretch the limits of VHF/UHF operating usually go for all-mode rigs that offer CW, SSB, FM and various WSJT digital modes. Again, back in the olden days, a VHF+ enthusiast would acquire single-band all-mode radios for the bands of interest. A ham really into VHF/UHF might have single-band radios for 6m, 2m, 1.25m, and 70 cm stacked up in the ham shack. The 1.25-meter band has always been a bit neglected in terms of equipment availability because that band is not available worldwide. Transverters are another option to get all-mode capability on these bands using an HF transceiver to transvert to a single VHF or UHF band.

HF Plus 6 Meters

One important addition to the standard HF rig is that the 6m band is often included. Now this may not sound quite right because we all know that 6 meters is a VHF band, so what is it doing in an HF radio? It actually makes a lot of sense because a lot of 6-meter operating is similar to HF. (6 meters is the VHF band that often emulates HF.) There is FM activity on 6 meters but most of the action is on SSB, CW, and, yes, FT8. In fact, FT8 is seeing a lot of action on the band, so if you want to participate on 6m, you should consider that mode. Anyway, this all means you probably need an all-mode radio for 6 meters, and having it as a bonus band on an HF radio without a huge increase in cost is a good approach. (These radios usually support FM for the 10m and 6m bands.)

The IC-7300 transceiver covers all the HF bands and 6 meters (50 MHz).

There are many great HF/6m radios to choose from so I won’t try to list them all. Some of the more popular ones in the $1k to $1.5k range are: Icom IC-7300, Yaesu FT-710, and Yaesu FT-DX10.

All-Band All-Mode Rigs

Another common transceiver configuration is the All-Band All-Mode radio available from several manufacturers. A great example of this type of radio is the Yaesu FT-991A, which includes 160m through 10m plus 6m, 2m, and 70cm. Once again, 1.25m is passed over. This radio configuration has a lot of appeal because it covers pretty much everything with all-mode capability. (It also has a built-in sound card and USB connection which is handy for the WSJT digital modes.)

The Yaesu FT-991A covers 160m through 10m, plus 6m, 2m and 70cm.

The FT-991A is a good choice for the ham shack or operating portable but it is a bit large for a mobile installation. Icom offers the IC-7100 in a mobile form factor, with a novel sloping detachable front panel. Yaesu used to offer mobile products in this space such as the very popular FT-857D transceiver. However, the FT-857D is no longer made and its apparent replacement is the FT-891 which has only the HF + 6m bands.

The Icom IC-7100 is a mobile rig with HF, 6m, 2m, and 70 cm.

The main disadvantage of this type of radio is that it can only do one frequency at a time. Often, I want to be able to work HF while still monitoring the local 2m FM repeater and simplex channels. Or maybe I’d like to keep listening for 6 meter activity while working 2m SSB, especially during a contest. However, this type of radio is my first choice for portable operating for Parks On The Air because it covers all the bands and modes. This article is focused on 100-watt radios but note that there are all-mode all-band QRP radios such as the IC-705.

All Mode VHF/UHF Radios

One interesting and disappointing trend that has emerged is the distinct lack of VHF/UHF all-mode transceivers. There is only one such radio on the market today, the Icom IC-9700 which does all modes on 2m, 70cm, and 23 cm (1.2 GHz). It seems that Icom decided that if they are going to offer a VHF/UHF radio, they would go full-featured and include 23 cm. Note that if you pair this radio with an HF plus 6m radio, you can cover all the popular bands with all modes using two radios. This radio is not inexpensive, currently selling new for about $1800.

The Icom IC-9700 is a VHF/UHF transceiver that offers all modes on 2m, 70cm and 23cm.

I suppose we can declare this the dominant design for VHF/UHF but it is a lone product in this space. I have written previously about an all-mode dual-band portable radio for 2m/70cm that I desire. I own an IC-9700 and like it a lot but I would give up the 23 cm band to have a radio that is more portable and less expensive. I suspect that Icom is happily making good profit margins on the IC-9700 given that they have essentially no competition in this space. Yaesu has the technology to do something here but has been content to let the FT-991A cover the all-mode 2m/70cm space for them.

Common Ham Shack Setups

Now let’s take a look at some common ham shack configurations that consider these different radio configurations. When I say “ham shack” that may include your mobile or portable station, too.

Setup 1: FM VHF/UHF Only A Technician might decide they want to focus on 2m and 70cm, with FM being just fine for working simplex and repeaters on those bands. A basic dual-band FM transceiver will handle this nicely, see A VHF FM Station at Home. For some hams, their dual-band handheld radio serves this purpose.

Setup 2: All-Band All-Mode Transceiver As mentioned earlier, All-Band All-Mode radios cover the most popular ham bands and modes with one rig. They are a good way to get one radio that does everything. The disadvantage is not being able to monitor VHF/UHF at the same time as working HF.

Setup 3: HF/6m radio plus 2m/70cm FM radio This is a very common configuration for a ham shack because it separates the HF bands (and 6m) from the 2m/70cm FM operating. The FM rig can be left monitoring your favorite repeater or simplex frequency while you chase DX on 15 meters. If your 2m/70cm needs are basic, the FM radio might even be a handheld transceiver.

Setup 4: HF/6m radio plus all-mode VHF/UHF radio This is the setup for the ham that wants to cover all the bands and be able to do all modes on VHF/UHF. The band/mode coverage is similar to Setup 2 but we have two radios available which provides the monitoring flexibility associated with Setup 3. This configuration allows for having a really good HF/6m radio and a really good VHF/UHF radio.

Conclusions

The ham radio transceivers being offered tend to follow certain patterns consistent with the dominant design theory. If you buy a modern HF transceiver, you will likely get all of the HF bands plus the 6m bonus band. These radios vary in features and performance but they all have good band/mode coverage. The VHF/UHF situation is perhaps not quite as simple. The standard 2m/70cm FM rig is a popular option but is limited to FM only. The VHF/UHF weak-signal enthusiast does not have many choices beyond the IC-9700, which may represent an opportunity for another manufacturer to jump in with a more cost-effective 2m/70cm all-mode radio. The 1.25m band continues to be neglected and may be a good additional band to add to 2m/70cm radios.

That’s my analysis. What do you think?

73 Bob K0NR

An Easy HF Antenna

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When radio amateurs get ready to put an HF station on the air, they often have questions about what antenna to use. The good news is that there are many options to choose from. The bad news is that there are too many options to choose from. It can be overwhelming. This post describes an antenna I just installed that is easy to put up and works well.

The ponderosa pine tree supports the endfed wire antenna.

Having 30-foot tall pine trees on our property, my usual approach for HF antennas is “wires in the trees.” I have several ropes strung up over these tall trees so that I can raise and lower wire antennas as needed. These ropes were installed using a slingshot to launch a fishing line over the top of the tree, then I pulled up a lightweight rope.

The 9:1 UNUN provides the matching at the end of the wire antenna.

End Fed Long Wire

The antenna is the EFLW-1K from MyAntennas.com, which is an End Fed Long Wire Antenna. (This should not be confused with an End Fed Half Wave antenna.) This antenna is intentionally cut to not be a resonant length on any of the bands. The 9:1 UNUN transforms the high impedance at the end of the wire down to something closer to 50 ohms. The match is not perfect so an antenna tuner is required to cover all of the bands. MyAntennas offers this antenna with different lengths of wire, with longer wires required to support the lower HF bands. I purchased the 53-foot version but decided to shorten the wire. My interest is working 20 meters and higher and I wanted the antenna to be mostly vertical, so I shortened the wire to 36 feet. The MyAntennas products are good but other similar 9:1 UNUN products on the end of a wire will work.

An endfed antenna like this needs some kind of counterpoise to balance out the antenna operation. Many people have written about this and there are many different approaches. The MyAntenna UNUN has a connector intended to support adding a short length of counterpoise wire. I could have gone that route but a decent length of coaxial cable lying on the ground can function as this counterpoise. So that’s what I decided to use.

The B11ISO isolation transformer is inserted in line with the coaxial cable.

I also added an inline isolation transformer to minimize the common mode currents getting back to the transceiver. I don’t know that this is required but I had one available so I used it. The antenna has 50 feet of LMR 400 coax laying on the ground which connects to the inline transformer. Then, another 25 feet of RG-8X coax connects the transformer to my transceiver. The internal antenna tuner in my Icom IC-7610 handles this antenna quite well, tuning up on 20m, 17m, 15m, 12m and 10m. This means I can instantly switch between the bands and be ready to go.

I’ve been running SSB, FT8 and FT4 on this antenna, working many stations in all regions: Europe, Asia, Oceania, Africa, North and South America. Conditions are great and I keep telling newer folks: now is the time to be on HF! This basic antenna is a great way to get on the air and work some DX.

73 Bob K0NR

Update (18 Jan 2024): I gave this antenna a try on 6 meters using the IC-7610 (with tuner) and it works on that band, too.
Update (05 Feb 2024): Just for fun, I tried the antenna on 30m and 40m. I thought it would be too short but the tuner in the IC-7610 was happy and I am making contacts on those two bands.

Improved IC-705 SOTA/POTA station

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This past year, Joyce/\K0JJW and I did quite a few Summits On The Air (SOTA) and Parks On The Air (POTA) activations, often as part of an RV camping trip. During this time, we made some improvements to our portable gear. For SOTA, we primarily use the VHF/UHF bands but we have been sprinkling in a bit more HF activity. For POTA, we often don’t have a Height Above Average Terrain advantage, so we definitely use the HF bands.

The ICOM IC-705 is a great backpack portable rig for SOTA and POTA.

Our main goal was to have a backpack portable station for SOTA and POTA that can cover HF through 70 cm, on the most popular bands/modes including CW, SSB, FM and FT8.

Using The IC-705

Bioenno Power Battery
This 4.5 Ah battery from Bioenno is a compact, lightweight battery for portable operating.

The Icom IC-705 is a great transceiver for covering most HF, VHF and UHF bands. With an external battery, the transceiver puts out 10 watts of RF power. (This is a bit less than the 50 watts from our Yaesu FT-90, which is our default choice for 2m and 70 cm SOTA.) We have accumulated a number of Lithium Iron Phosphate batteries from Bioenno. They are all set up with PowerPole connectors and are easily interchanged. See a previous post, My SOTA Battery Journey.

Arguably the biggest weakness of the IC-705 is the lack of an internal antenna tuner for the HF bands. Of course, you can operate without a tuner by making sure your antenna is always 50 ohms. I find that limiting, especially under portable conditions where the antenna configuration might be compromised. Also, some common end-fed antennas that cover multiple bands are not a good match for all bands. There are external automatic antenna tuners available for the IC-705, so initially those looked like a good solution. Then I remembered that I had a small MFJ-902 Travel Tuner that could do the job. The MFJ-902 is a classic T-network with two variable capacitors and one variable inductor. I gave it a try and was impressed with how easy it was to tune using the SWR meter of the IC-705. This thing is simple and it works.

The MFJ-902 Travel Tuner is a simple T-network antenna tuner.

The rear panel of the tuner has two SO-239 connectors, one for the transceiver and one for the antenna. I put a BNC adapter onto the transceiver port and used a short BNC cable to connect to the IC-705.

The rear panel of the Travel Tuner, with an SO-239-to-BNC adapter installed.
A typical picnic table setup using the IC-705 with the MFJ-902 tuner.

The Travel Tuner is compact and not very heavy, so it works out well for backpack portable use. It can handle up to 150 watts, which is overkill for the IC-705 but it may come in handy when used with a higher power transceiver. Still, I am on the lookout for an even more compact (probably lower power) manual antenna tuner.

A typical end-fed half-wave wire antenna for 15 meters.

We have collected a variety of HF antennas, focused mostly on 20 meters and higher. These are typically end-fed, including single-band half-wave designs as well as multiband random-length antennas. These are used in the classic SOTA configuration with one end of the wire supported by a lightweight fishing pole and the coax connection on the ground, fed by a 25-foot length of RG-8X coaxial cable.

FT8 Solution

With the popularity of FT8 on the HF bands as well as 6 meters, I figured we should include that mode in our portable kit. My first thought was to use a compact Windows computer running the standard WSJT-X software. Ultimately, I chose the SDR Control app for the Apple iPad (by Marcus/DL8MRE), which supports specific Icom radios. The iPad connects to the IC-705 via its WiFi connection, which simplifies the connection/cabling challenge. The SDR Control app does cost $49.99, so it is not your inexpensive iOS app but I have found it to be worth the price. Because this app is focused only on iOS and certain Icom radios, it is well-tuned to be a no-fuss solution. I am currently using the app only for FT8 but it has other features and modes for me to explore.

The portable station for FT8, running SDR Control on an iPad.

The Powerwerx PWRbox is shown in the photo above, which we often use for operating POTA. (This box is a bit heavy for hiking.) The PWRbox holds a 20 Ah battery as described here. Also shown in the photo is a handy little stand for the IC-705, the NEEWER Folding Z Flex Tilt Head. It does a great job of holding and stabilizing the radio at a variety of angles. (Hat tip to Kyle/KD0TRD.) It is also a little heavy for backpack portable, so it usually gets left behind on a hike.

The Maxpedition bottle holder case works well with the IC-705.

For a protective case for the IC-705, we use the Maxpedition 12-Inch X 5-Inch Bottle Holder. I’ve seen other IC-705 users recommend it and OH8STN mentioned it on his blog. At first glance, the case seems a bit large but this provides enough room inside to stow a small Bioenno battery and other accessories. The side pouch is a good place for storing the microphone and power cord.

Wrap Up

This post shares some new equipment configurations we are using for SOTA and POTA, mostly focused on the IC-705. I really like that radio for portable ops as it is the best solution for operating HF through UHF. The SDR Control software on an iPad has also turned out to be a win for us.

What are you using for your portable station?
Do you have any tips or other operating ideas?

73 Bob K0NR

KB1HQS Arrow Antenna Mods

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I am a big fan of the Arrow II style antennas for VHF SOTA. Initially, I used the dualband 2m/70cm antenna for satellite work as well as mountaintop activity. This started before SOTA was even a thing, as I hiked in the Colorado mountains and made radio contacts just for fun. These days, we normally carry the 2m-only version of the antenna, with split boom and 3 elements. My personal seamstress (Joyce/K0JJW) worked up a really nice rollup case for it. Sometimes, we’ll take along a separate 5-element 70 cm Yagi, which can remain fully-assembled and strapped onto my pack.

Stuart/KB1HQS has been experimenting with various modifications of the Arrow II antennas. Recently, he put together a video of his mods, well done and interesting:

Ultimate Arrow Antenna Modifications

All antennas are a compromise between cost, size, weight, performance, convenience, and durability. I have found that the 3-element Yagi from Arrow fits my needs really well. I have not been motivated to modify it. The Arrow antenna has a gain of about 6 dBd and is 37.5 inches long. We handhold the antenna and that is about as big/long as I’d like to hold. I am still in search of a higher-gain antenna for those special situations when I know that a few more dB of gain could make a difference. I’ve not really found anything I like. A longer boom would likely require a mast and, therefore, a guy system, which adds more weight and complexity.

K0NR operating 2m FM from a summit using the Arrow II 3-element Yagi antenna.

Antennas are a never-ending source of options and experimentation, so go out and try something new.

73 Bob K0NR

Checking Out The KT-WP12 Transceiver

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I’ve been interested in the idea of a microphone-centric radio and wrote about it here: How About a Mic-Centric Mobile Transceiver? Shortly thereafter, I discovered that QYT has introduced a VHF/UHF ham rig that has the display and controls in the microphone (Model KT-WP12).

You may want to watch the video by Tech Minds, which does a good job of introducing the radio.

I was very keen on trying this radio out, so I purchased one, paying about $110.

On the Bench

First, I did some bench tests to check the basic performance of the radio. The receiver sensitivity, transmit frequency and FM deviation all looked very good. The one specification that was disappointing was the RF power output. On the 2m band, the output power was 20.6 W, while the 70cm band was 15 W. The specification for the radio is 25 W. The power was measured using an HP 8920A RF Communications Test

I’ve noticed this on other radios from Chinese manufacturers: the basic specs of the radio check out, except the RF power level is low.

User Interface

As you might expect, cramming all of the controls into the microphone is a challenging user interface design. I spend quite a bit of time playing with the radio at home before actually using it on the air. Overall, I found the user interface to be acceptable, but several areas that should be improved.

QYT relies on the menu system to provide control of many of the settings. This is similar to the various Chinese handhelds where you push the MENU button to access the menus, followed by UP/DOWN to sequence through the menus, followed by MENU to access the specific setting. Then the UP/DOWN buttons choose the value of the setting and another push on MENU to accept it. The volume control setting is buried in this menu system, which seems like a poor choice. Fortunately, Mick/M0VMK pointed out that the volume can also be set by enabling the monitor feature (big button on the top of the mic) and hitting UP/DOWN.

The portable SOTA station with Bioenno battery.

This design depends too much on the menu system. A few user-defined buttons would be a real help. This radio could benefit from a serious redesign using User-Centered Design.

This radio has one receiver but allows for three independent frequencies to be displayed simultaneously. There is a scanning mode that tries to emulate a multi-receiver radio. This too is all too common with the Chinese radios…somehow they have it in their heads that this adds value for the user. My experience is that it mostly confuses the user. Most users would be better served with a single frequency display, supplemented with dual-watch and scanning capability.

You probably won’t be surprised that the user manual is terrible, also common with Chinese manufacturers, but this one is particularly bad. Same with the programming software…it mostly works (I had a few crashes) but it is poorly written.

On The Air (SOTA)

I was very interested in trying out this radio for Summits On The Air (SOTA) use. The idea is that the radio can be stuffed into a fanny pack, with the microphone, speaker, display, and controls in your hand.

The QYT radio stuffed into a fanny pack.

The basic concept of holding everything in the palm of my hand worked out quite well. The display was visible in bright sunlight, the speaker audio was clear, and the microphone worked great. I made a number of SOTA contacts and received good signal reports. I held the microphone in one hand and pointed the 3-element Yagi antenna with the other hand. (Joyce/K0JJW assisted with logging and we took turns working the SOTA chasers.)

As soon as I fired up the radio, I heard interference on the 2m band, not very strong but noticable. It sounded like it was coming from an FM broadcast station. Pointing the Yagi antenna in the direction of the FM station on the adjacent mountain seemed to confirm the source. I did not hear any interference on the 70cm band. I’ve operated from this SOTA summit before and have not noticed any interference with other equipment, including Yaesu handhelds. Also, I switched to my Yaesu FT-90 and the broadcast station was not heard. As various people have suspected, this indicates that the receiver in the QYT is not very robust in terms of rejecting off-channel signals. Of course, this is an anecdotal report, not based on bench measurements.

Bob/K0NR on a SOTA summit with the KT-WP12 in a fanny pack.

I also encountered an anomaly where after my transmission, the radio did not revert back to receive quickly. There was a few seconds where no audio was coming out of the transceiver. This caused me to miss a few responses to my CQ call. This issue requires some additional investigation. It may have just been operator error on my part. However, I suspect that the radio was probably locking onto another frequency but I am not sure (see previous comments about the three frequency scanning mode). So file this issue under “stay tuned for more information.”

Note that I did not use the radio very much on repeaters, focusing on SOTA simplex operating with no transmit offset or CTCSS.

Conclusion

On the positive side, I really like the microphone-centric approach that this radio uses. The user interface can be improved but it is good enough.

The two big limitations of this radio are 1) low RF power output and 2) weak off-channel receiver performance. Now you might say that the RF power is not off by that much but my interest is having a SOTA radio that greatly exceeds the power of a typical 5 W handheld. On the 70 cm band, this radio only put out 15 W, so only 4.7 dB better than a handheld. The poor receiver performance will tend be an issue on summits that have radio installations nearby. In some cases, this can completely prevent a VHF SOTA activation.

I will probably use this radio again for SOTA activations but I’ll be bringing along a backup rig, just in case.

Power Box for Bioenno Battery

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When operating portable, I use Lithium Iron Phosphate batteries from Bioenno. Most of my portable operating is for Summits On The Air (SOTA) and I wrote about it here:

My SOTA Battery Journey

For POTA activations, I purchased a larger, 20 Ah Bioenno battery and use it to power a Yaesu FT-991 (and other radios). This battery has worked out really well. It is a bit large for backpack portable and weighs 5.4 pounds, but I have taken it along on a few SOTA activations.

Powerwerx PWRbox

I decided the battery could use a case to protect it while being tossed around in the back of the Jeep. Powerwerx has a really good battery box that includes a digital voltage readout, automotive (“cigarette lighter”) socket, dual PowerPole plugs and high-current binding posts.

The Powerwerx PWRbox

Initially, I did not think I needed the extra gizmos, and I did not want to take up more space with the battery system. Later, I figured that I could always pull the battery out of the box and use it in its original form.

The top of the battery box, with the connector covers open.

The power switch is handy for turning on/off the battery power and the digital voltmeter provides a simple view of the battery condition. Most of the time, I use the PowerPole connectors to connect up my radios but occasionally the automotive socket comes in handy.

The 20 Ah Bioenno battery sits inside the box with plenty of room to spare.

I used some of the plastic packing material that came with the box to hold the battery in place. A little bit of cutting with a sharp knife produced a good fit. There is enough room above the battery for the Bioenno charger, so it makes for a nice kit. The charger connects to the original charging plug on the battery.

The wiring underneath the lid of the box.

As expected, Powerwerx did a good job of wiring up the various components and included fuses in both the positive and negative cables. The box is big enough to hold a 40 Ah battery and I am tempted to upgrade it for larger capacity, but the 20 Ah battery has been sufficient, so far.

I’ve used this battery box for multiple POTA activations and a few other situations when I just needed to power up a radio at home. It works great. The voltmeter gives me a quick check of the battery status and the PowerPole connectors make for easy hookup.

The PWRbox costs $109.99, battery not included.

73 Bob K0NR

One Radio To Rule Them All (Ham, GMRS, FRS, MURS)?

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The common Baofeng UV-5R can transmit and receive on a wide range of frequencies…but not necessarily within FCC rules.

From time to time, the question is raised about using radio equipment in multiple radio services. One common example is a licensed radio amateur that wants one radio to cover the Family Radio Service (FRS), General Mobile Radio Service (GMRS), and the 2m/70cm ham bands. Some people also want the Multi-Use Radio Service (MURS)…or maybe even marine VHF or aircraft VHF. The thinking goes that if one radio can transmit and receive on all these frequencies and that person is authorized to use those frequencies, then one radio can do it all.

This seems like a reasonable objective but the problem is that the FCC has a few rules and regulations that come into play.  This leads to an important note: I am writing about the FCC rules and regs here…you may choose to ignore them but that’s on you.

Part 97: Amateur Radio Service

First, the good news. The Amateur Radio Service, governed by FCC Part 97, has very few restrictions on the type of equipment you can use. Heck,  you can build a transceiver from parts and put it on the air. So the ham rules are not going to be a major limitation.

Part 95: FRS, GMRS and MURS

FRS, GMRS, and MURS radios are governed by FCC Part 95.  Section 95.591 says this about FRS radios:

§ 95.591 Sales of FRS combination radios prohibited.

Effective September 30, 2019, no person shall sell or offer for sale hand-held portable radio equipment capable of operating under this subpart (FRS) and under any other licensed or licensed-by-rule radio services in this chapter (devices may be authorized under this subpart with part 15 unlicensed equipment authorizations).

Section 95.1761 says this about GMRS transmitters:

(c) No GMRS transmitter will be certified for use in the GMRS if it is equipped with a frequency capability not listed in § 95.1763, unless such transmitter is also certified for use in another radio service for which the frequency is authorized and for which certification is also required. No GMRS transmitter will be certified for use in the GMRS if it is equipped with the capabilities to operate in services that do not require equipment certification, such as the Amateur Radio Service. All frequency determining circuitry (including crystals) and programming controls in each GMRS transmitter must be internal to the transmitter and must not be accessible from the exterior of the transmitter operating panel or from the exterior of the transmitter enclosure.

(d) Effective December 27, 2017, the Commission will no longer issue a grant of equipment authorization for hand-held portable unit transmitter types under both this subpart (GMRS) and subpart B of this part (FRS).

The Midland MXT400 is a typical GMRS mobile transceiver.

Similarly, MURS radios have this restriction (Part 95.2761):

(c) A grant of equipment certification will not be issued for MURS transmitters capable of operating under both this subpart (MURS) and under any other subparts of this chapter (except part 15).

The FCC is saying (requiring) that FRS, GMRS and MURS radios must work on their designated frequencies and nothing else. At one time, it was legal to sell a combination FRS/GMRS radio but the FCC has specifically removed that option. Part 95.1761 seems to leave an opening for a GMRS radio that is also certified for use in another radio service, but that is a very thin opening and it specifically excludes the Amateur Radio Service.

Now, why would the FCC put these restrictions in the regulations? The answer is pretty simple: these radio services are intended to be used by everyday, non-technical folks. The radios need to be simple to use and not include the capability to wander off onto any old frequency. Hence, the rules lock down the frequencies that the radios can use.

(As a side note, this regulatory approach is good for amateur radio. Imagine if FRS radios had Channel 30 set up to transmit on 146.52 MHz, with a note in the manual that says “only use this channel if you have an amateur radio license.” We would have a crapton of unlicensed operating on 2 meters.)

Part 90: Private Land Mobile Radio Services

Part 90 regulates a broad range of land mobile radio, including public service, police/fire, search and rescue, forestry, utilities, and businesses. Licensing is very specific under Part 90. A radio license will specify a particular set of frequencies allowed, specific power levels and emission types, and even the allowed operating location of the radios.

Radios designed for Part 90 are usually programmed by a radio tech to operate only those specific frequencies that a licensee is authorized to use. This results in a relatively simple operating set up with the user just selecting from the preset channels on the radio. Part 90 radios normally cover a wide range of frequencies so that the manufacturer and the radio shop can sell one radio model to any licensed user.

In many cases, these Part 90 radios cover the adjacent amateur bands, such as 2m and 70cm. (For example, the Anytone AT-D878UV is Part 90 certified and covers 140-174 MHz and 400-480 MHz.)   So this does open up the possibility of using a Part 90 radio under a Part 90 license and using it on the ham bands. A typical scenario is when a Search and Rescue member has a Part 90 radio set up to use the S&R frequency as well as the 2m/70cm amateur bands. The key to this is starting with a radio that is Part 90 certified and then programming it for the amateur band.  Of course, you need to be authorized to use the Part 90 frequency and have an amateur radio license.

Getting Creative on Radio Configuration

A few years ago, Anytone Tech tried to market the TERMN-8R VHF/UHF radio as legal for the ham bands, GMRS, MURS and Part 90 use.  An early review of this radio is here on the PD0AC blog. Basically, the radio had three distinct operating modes: GMRS, MURS, and Commercial/Normal. Initially, the FCC approved the radio but later took a closer look and canceled the authorization. The TERMN-8R is still available but without the three modes. It is marketed as a Part 90 radio that also does the amateur bands.

The Anytone TERMN-8R handheld transceiver.

I recently became aware of the Anytone AT-779UV which is sold in the USA as a Part 95 GMRS radio. However, using the programming software, the radio can be configured to cover the 2m and 70cm amateur bands or a much broader range of frequencies (136-174 & 400-470 MHz). If you change the radio configuration to operate on the ham bands (or wider), the radio is no longer Part 95 certified. The configuration via software takes some knowledge and effort so it is not a mode that you can easily switch back and forth. It is really no different than other software-programmable radios.

 

 

 

Wrap It Up

So there you go, your dream of One Radio To Rule Them All (FRS, GMRS, MURS, and the 2m/70cm ham bands) is not going to happen. At least not legally. You can configure a radio to do this…but it will not meet FCC regulations.  However, you can configure a Part 90 radio to operate legally on Part 90 frequencies and on the amateur bands.

A Decibel Is Still A Decibel

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When discussing signal levels and power output, hams like to say things like:

Using higher power isn’t important because it only gives you one additional S unit

and

You’ll lose some power in the coax but you won’t even notice a few dB

These statements are often true and at the same time may be completely wrong. I’ve noticed that radio amateurs pushing the limits of their station pay close attention to every decibel they gain or lose. This is especially true at VHF/UHF frequencies where signals may be weak. A dB here, a dB there, the next thing you know it adds up to something big!

Definitions

First, let’s make sure we have a few definitions right. The decibel (dB) is defined as the ratio of two power levels:

dB = 10 log (P2/P1)

One decibel corresponds to a 26% increase in power level. A well-known rule of thumb is that doubling the power corresponds to a 3 dB increase. Similarly, chopping the power in half drops the signal level by 3 dB.  A 10 times increase in power is 10 dB. (Voltage can also be used to calculate decibel relationships but to keep it simple, I’ll just use power.)

The S Unit is normally defined as a 6-dB change in signal level, which is a factor of 4 in power. (Your S meter may or may not actually follow this rule but that is a topic for another day.)

Power Level

Let’s compare a few different power levels to get a feel for how decibels and S units behave. Let’s use a 5 watt QRP level as our reference power. If we crank up the power to 100 watts, we  have 10 log (100/5) = 13 dB increase in power level. This is slightly more than two S units (2 x 6 dB), so we would expect the S meter on the other end to read 2 units higher.

Now suppose we kick in our linear amplifier to produce a 1 kilowatt RF signal. This power level is 10 log (1000/5) = 23 dB higher than the 5 watt signal, or roughly four S units.

Now if our QRP signal was a solid S9 to start with, adding another 23 dB on top of it may not be that significant. The station can be heard at S9 or can be heard even louder at S9 + 23 dB. Except when there’s a pile of stations all calling that rare DX…then the loudest station tends to be heard. Crafty operating skill and good luck may overcome the power difference.

But consider the other extreme. Our QRP station is being heard right at the noise floor on the receive end. The two stations are struggling to complete the contact and the propagation path degrades by 2 dB. Now the QRP station is below the noise and uncopyable. We increase our power to 100 watts and gain 2 S units…still not very strong but the ability to receive the signal improves dramatically. Crank it up to 1000 watts and you gain another couple of S units and the copy is quite good. The key point is that changes in signal level matter most at the margin, when you can just barely copy the signal. (By the way, there is nothing wrong with running QRP…many ops enjoy the challenge of making contacts with low power.)

At the receiver, our ability to recover the signal is determined by the signal-to-noise ratio (SNR). A higher noise floor at the receiver means it will be more difficult to hear the signal coming in. The type of modulation being used may also make a big difference. Good old CW and the WSJT modes use a narrower bandwidth and will get through when wider-band modulation (SSB, FM) fails. In all cases, a stronger signal works better.

Antennas

Antenna systems also increase our signal level…and they do it for both transmit and receive. I recently did some comparisons of VHF antennas from a SOTA summit. My 2m Yagi antenna has 6 dB of gain (referenced to a dipole) and my comparisons showed that the performance of this antenna was good enough to pull some signals out of the noise to be solid copy. This occurred when the other station’s signal was right at the noise floor (using my lower gain antennas) such that the 6 dB improvement had a significant impact.

Sometimes hams will say that VHF is just line-of-sight propagation and that the signal level doesn’t matter much. This is partially true but often we are stretching for contacts beyond line-of-sight. Take a look at this article: The Myth of VHF Line-Of-Sight. This is another case where we are operating on the margin and every dB matters.

Feedline loss can cause us to lose decibels, which impacts both transmit and receive performance. If your coaxial cable is short, then the losses may be negligible. Increasing cable length and increasing frequency produce more loss. For example, 100 feet of RG-8X has only 1.1 dB of loss at 10 MHz. Increase the frequency to 146 MHz and the loss jumps to 4.5 dB, using the Times Microwave cable calculator. That means 50 watts of power at the transmitter turns into 17.7 watts at the other end of the cable. Using LMR-400 coax reduces the attenuation to 1.5 dB.

Summary

You can choose to ignore small changes in your signal level. A dB here or there may not make a big difference with casual ham radio operating. But these losses tend to add up and may become significant. Most importantly, just a few dB may be the critical difference between making a radio contact or not, when operating at the margin.

Parks, Summits and Roadtripping

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Getting out on the road and exploring is always fun, especially if you have ham radio on board. Joyce/K0JJW and I have been doing quite a bit of travel lately and we just completed our longest road trip so far with our RV.

Overview of the trip: Colorado to Key West, Florida and back again.

Our main destinations for the trip were four national parks: Congaree NP, Biscayne NP, Everglades NP, and Dry Tortugas NP. This determined the main route but we also found plenty of other things to do along the way. We started in Colorado, cut the corner across New Mexico into Texas, then east through Oklahoma, Arkansas, Mississippi, Alabama, Georgia and South Carolina. Then we headed south to Florida and ended up in Key West. Our return trip followed the gulf coast back to Texas, then back home.

Travel Philosopy

Planning a trip is full of trade-offs, so it is useful to have a general approach that the participants agree on. Our approach to this trip was to not drive too far every day but drive enough to hit the various places we wanted to visit. We are still working to find the right balance. This trip lasted 39 days, covering 6000 miles, which is about 150 miles per day. Some days we drove very little and other days were longer, maybe 400 miles.

Although the trip was created around the national parks, we filled in with interesting stops along the way. In particular,  we like to camp at state parks: the campgrounds are great and there’s usually something interesting about the park to enjoy. And did I mention they are natural Parks On The Air (POTA) opportunities? We also tried to work in some Summits On The Air (SOTA) activations that are relatively easy to access.

Rocky Victoria

Our recreational vehicle (RV) is a 2018 Winnebago Paseo, built on a Ford Transit chassis. We named her Rocky Victoria, using non-standard phonetics, but usually just refer to her as “Rocky”.

Rocky Victoria is our Winnebago Paseo RV.

Compared to your typical car or SUV, this Class B RV is huge. Compared to other RVs, this vehicle is small, about 22 feet long, usually fits in a standard parking space. With all of the normal RV stuff installed (stove, microwave, sink, refrigerator, toilet/shower combo, bed, etc.) there is not a lot of room left for personal gear.

Rocky fits us really well because it is easy to drive, getting in and out of places without much hassle. Also, setup and tear-down time at a campsite is minimal. One limitation is poor ground clearance, which is fine for forest service roads in good condition but not appropriate for offroad use. This affects what SOTA and POTA activations we do.

Radio Gear

We have an ICOM IC-2730A in Rocky, for normal 2m/70cm FM comms while running down the road. The antenna (not visible in the photo) is just a short whip on the driver’s side of the hood.

Rocky is not a big RV so by the time we load up all of our stuff, it is full. So the radio gear (and everything else we take along) must follow the backpacker principle of “take only what you need, use what you take.” No room for extra stuff you don’t use.

For this trip, we took along two ham stations:  A basic VHF SOTA station and a capable, picnic-table POTA station.

VHF SOTA Station

The VHF SOTA station is very compact and easy to carry. It covers the 2m and 70cm bands on FM, which is usually sufficient for us. The RF output power is only 5W, so it does not have the punch of one of our higher power radios. Not a bad tradeoff though.

Two Yaesu FT-1DR 2m/70cm handheld transceivers
Arrow 3-element Yagi 2m antenna
Two RH 770 dualband SMA antennas
HT chargers and other accessories

Picnic Table POTA Station

The POTA station is built around the FT-991, which is a 100 watt transceiver (HF/VHF/UHF) that is reasonably compact. We use a 20 Ah LFP battery to power the radio so it is portable and independent of the RV power sources.

Yaesu FT-991 Transceiver (HF, 6m, 2m, 70cm)
End-fed halfwave antennas for 40m, 20m, 17m, 15m, 10m
Roll-up j-pole antenna for 2m/70cm
20-foot fishing pole to support antennas
Two 25-foot lengths of RG-8X coaxial cable
12V, 20 Ah LFP Battery (Bioenno Power)

Joyce/K0JJW operates the picnic-table POTA station.

The POTA station does a great job at a campsite, usually on a picnic table. The POTA station fits inside my Kelty backpack so it can be taken for a hike. It is a bit heavy for a typical SOTA summit but works OK for drive-up and short-hike summits. It can also be set up inside the RV if required.

Single-band end-fed halfwave antenna (PAR EndFedz) for 20 meters.

Typically, we are going to try operating on 20m or 17m so that the halfwave antenna easily hangs from the fishing pole support. Depending on conditions, we often have to use 40m which takes a little more work to hang. Not a huge problem, though.

Collapsible fishing pole for supporting wire antennas.

For portable operating, I’ve tended to use a variety of end-fed wire antennas supported by a non-conductive pole of various sizes. For this trip, we used a 7 meter (21 feet) telescoping fishing pole that collapses to about 30 inches.  This pole will fit into my SOTA backpack.

20m halfwave antenna supported by the fishing pole mounted on the RV. (The 20m halfwave needs to be hung at an angle to be supported off the ground.)

To support the fishing pole directly from the RV, I attached a short length of plastic pipe to the ladder. It is a simple matter to slide the pole into pipe, resulting in the top of the pole being about 26 feet off the ground.

A short piece of plastic pipe is attached to the RV ladder so the fishing pole can be easily inserted.

The combination of the two stations gives us a lot of options for ham radio operating.

Summits On The Air

We activated three summits along the way: Mount Scott (W5O/WI-002) in Oklahoma, Choctaw County HP (W5M/MS-001) in Mississippi, and Monte Sano Mountain (W4A/HR-002) near Huntsville, AL.

Monte Sano Mountain is just east of Huntsville, AL inside Monte Sano State Park.

Monte Sano Mountain turned out to be a unique location because it is located in the Monte Sano State Park. The park surrounds the summit, which is broad and flat. We determined that the park campground is within the activation zone, so we camped there and did both SOTA and POTA activations.

Parks On The Air

We did a number of POTA activations along the way. This was done opportunistically, typically in the afternoon after we had set up our campsite. Our radio operating used SSB on 20m or 40m, along with a few 2m FM contacts.

K-0688  Lake Meredith National Recreation Area   US-TX
K-1090  Lake Chicot State Park   US-AR
K-1048  Monte Sano State Park  US-AL
K-0017  Congaree National Park US-SC
K-1832  Anastasia State Park  US-FL
K-0024  Everglades National Park  US-FL
K-0635  St. George State Park  US-FL
K-2992  Brazos Bend State Park  US-TX

Every one of these activations was a lot of fun. There’s nothing like sitting outdoors in the sunshine working a pileup of enthusiastic POTA hunter stations.

Summary

In this post, I emphasized the ham radio activity during this trip. Radio operating was not our main goal but it was a big part of the overall experience. Joyce and I had a fantastic time touring this section of the country, and we are looking forward to our next trip.

73 Bob K0NR

Here’s the SOTA Transceiver I’d Really Like

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Joyce/K0JJW and I did another activation of Mt Herman (W0C/FR-063) today. This is a repeat summit for us this year but we were looking for an easy hike not too far from home.

The Yaesu FT-90 transceiver is small and lightweight, perfect for portable operating when you need a little more RF power.

As usual, we were just using the VHF/UHF bands for the activation. My favorite rig for this type of SOTA activation is a Yaesu FT-90, a very compact mobile transceiver (4 x 1.2 x 5.4 inches) that is no longer manufactured. It has a unique heatsink with an integral fan that can handle the heat from the 50-watt transmitter.  We use a Bioenno 4.5 Ah LFP battery to supply the power for the radio.

I was trying to work Bob/W0BV about 65 miles away and we were not able to complete the contact. The distance is not too difficult but there are several mountain ranges in the way. Sometimes we can get the electromagnetic waves to sneak through, but not today. Hiking down the mountain, I was thinking about how we could have probably made the QSO on SSB or CW, instead of FM.  I chose not to bring the all-mode transceiver (FT-817) along today, so that was not an option.

That is when the idea hit me. The FT-90 is the right form-factor and power level for VHF/UHF SOTA but it is limited to FM. Yaesu, if you are listening, here’s what I’d really like to see in a small mobile transceiver:

  • FT-90 size radio, perhaps a little larger but not much
  • 2m and 70 cm bands (include 1.25m if you’d like)
  • At least 25 watts of output power, more would be better (say 50 watts)
  • All mode capability (CW/SSB/FM/Digital), sure go ahead and toss C4FM in too.
  • No internal battery…I’m going to have to use an external battery anyway to get enough battery capacity

At various times, I have had people ask “why don’t they put SSB in handheld radios?” They recognize that SSB has weak-signal advantages over FM, so they wish their handheld transceiver (HT) could do it. I say rather than shove more features into an HT, put it in an FT-90 size radio. It would be a much more usable solution.

Although I arrived at this radio concept thinking about SOTA, it would also be a great mobile rig for general use. The FT-90 was popular because it was very compact AND it had a removable faceplate that could be mounted almost anywhere. There really is no way to get VHF/UHF SSB into a vehicle other than those all-band radios like the FT-857 and the IC-7100. Oh, did I say FT-857? Sorry, that model has been discontinued. The satellite operators will love it, too, especially if it could work 2m/70cm crossband full-duplex.

So there you go, Yaesu (or Icom)…a fantastic product concept at no charge. I would be happy to beta test it for you.

That’s my idea for today. What do you think?

73 Bob K0NR

Best VHF SOTA Antenna?

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Charlie/NJ7V and Gaston/KT1RUN did a comparison of VHF antennas during a SOTA activation. Specifically, they compared a rubber duck antenna, a J-pole antenna on a tall mast, and a 3-element Yagi antenna. Spoiler Alert: the rubber duck sucks (they all do) but the Yagi and J-pole performed about the same.

Joyce/K0JJW and I use the Arrow 3-element Yagi antenna for most of our SOTA activations, so I am very familiar with that one. We also have a rollup J-pole that we use once in a while.

Charlie used the Yagi the same way we do: handheld at ground level. The J-pole was on a mast, maybe 12 feet (?) in the air. Although they were on a summit, there is some performance improvement getting the antenna higher than the surrounding terrain. The gain of the Arrow 3-element Yagi has been measured at about 6 dBd. The gain of a J-pole, being a halfwave radiator, is 0 dBd. The additional height of the J-pole has to make up this 6 dB of gain difference to be roughly equivalent.

A big difference, though, is that the Yagi antenna has to be held and pointed. The J-pole is always pointing in the right direction so you can just focus on operating and logging. We may have to consider using a omni antenna instead of the Yagi.

Good stuff!

73 Bob K0NR

Choosing A First Handheld Radio

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Once again, I was asked by a new ham “which handheld transceiver should I get?” This is a frequent and valid question that comes up. Often the question gets framed as “Baofeng or something better?” I say “something better.”  I am not writing to bash Baofeng radios or the people that use them. The radios are an incredible value on the low end of the market…amazing what they can do for $30 or so. Besides, I own several of them.  I just think that if you have a few more $$ to spend, you can get a much better radio. What’s wrong with these low-end Chinese radios? Out of spec harmonics on transmit and poor adjacent channel rejection on receive.

Digital? Probably Not

The other question that usually surfaces is “should I get a digital radio?” Here “digital radio” means D-STAR, Yaesu Fusion or DMR. My answer to that is “No,” unless you have a specific reason for going digital. Adding digital to a radio results in two things: 1) a higher price and 2) a more complex radio. Actually, the price difference may not be that significant, especially for a DMR radio. However, the complexity factor is always there.

What is a specific reason for going digital? You already know that there are digital repeaters in your area that you want to use, you have ham radio friends already using digital or you are technically-oriented and have researched the topic to know that it is something you want to try. If one of these things is true, then go for it.

Oh, you do need to know which digital format to get. No radio does them all and the industry is fragmented between D-STAR, Fusion and DMR. I find this very disappointing but life is sometimes like that.

Narrowing It Down

So narrowing the topic down, we are looking for an affordable (under $100) dual-band handheld that is not a cheap Chinese radio (Baofeng, etc.) and is not a fancy digital radio. My opinion is the quality ham radio manufacturers are pretty much Alinco, Icom, Kenwood, and Yaesu. The price points on basic handheld transceivers keep changing, so be sure to check the date on this post and do a little price shopping.

The Alinco DJ-VX50 is about $100, so not too expensive, but I am not seeing any eham.net product reviews on it. Also, it seems to be out of stock at several vendors, so I am not sure of its production status. Icom and Kenwood have exited the low-end handheld market, so nothing to consider there. This leaves Yaesu as the only “brand name” player in this space. I have been recommending the Yaesu FT-4XR as a good alternative: see What About the Yaesu FT-4XR? at about $80. I recently noticed that the Yaesu FT-65R has come down in price to about $85. With this price difference, it probably makes sense to go with the FT-65R. (I really wonder about Yaesu’s product line strategy at this point. Why are there two similar radios priced so close together?)

Here is a quick comparison of the two radios: Yaesu FT-4XR vs FT-65R, which is right for you? Conclusion: FT-65R is probably better for most people. Also, check out the HamRadioSchool.com article: Yaesu FT-65R Product Review.  The eham.net product reviews are generally positive on the FT-65R, but there are a few negative themes that surface. Some people are reporting radio failures that may indicate a manufacturing issue with the product. (It is made in China.)

The Good Old FT-60

The other theme that surfaces is that the FT-65R is not a complete replacement for the venerable FT-60R. Joyce/K0JJW and I have a couple of FT-60Rs that we really like and frequently use. Yaesu still sells this older model because it is so popular and, frankly, it is a really solid radio. The HamRadioSchool.com review of the FT-65R mentions several things that people tend to like on the FT-60R that were left out of the FT-65R (e.g., dedicated VFO and Squelch knobs.) The biggest complaint I hear about the FT-60R is that it has an old-school NiMH battery (the FT-65R has lithium-ion).

My conclusion is to recommend the FT-65R to newcomers to the hobby. At ~$85, it fits most people’s budgets. There is some risk that you will outgrow it down the road and want a more capable handheld for digital or APRS or whatnot. In that scenario, the FT-65R will still be a good second/backup radio. (Ya gotta have more than one, right?)

That’s my opinion. What y’all think?

73 Bob K0NR

How Much Does Emergency Power Cost?

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Some folks are criticizing the ARRL for not modifying the Field Day rules in response to the Wuhan virus epidemic. Most of them are looking for a way to operate Field Day from home but still have a club score of some kind. I posted my thoughts here: Don’t Mess With The Field Day Rules.

The Field Day (FD) rules allow for a home station with commercial power to participate in FD as a Class D station. However, Class D stations cannot work other Class D stations for points. If the home station has emergency power (batteries, gasoline generator, etc.), then it is a Class E station that can work all FD stations for point credit.

Emergency Power: Too Difficult?

I’ve heard some hams argue that it is too difficult to set up emergency power for their home station. In many cases, the argument is actually that it is too expensive to do this.  I can see this point if you run out and buy a name brand gasoline generator…a Honda EU1000i costs about $950.

This raises the question of what is the lowest-cost way to equip a home station for emergency power?  Let’s consider the case of a typical 100W HF transceiver such as an IC-7300 or FT-991A. These radios require a 12 V power supply at 22 A maximum on transmit. Receive current is much lower, typically 1 to 2 A. Under FD rules, we don’t need to power our computer or other accessories from emergency power, just the radio. [Update: if the computer performs the keying of the transmitter, as in WSJT modes, it must use emergency power.] If we assume a 50% duty cycle, this class of radio consumes about (22+2)/2 = 12 A average current. (Yes, you could choose to operate QRP and really stretch the battery but let’s stay with the 100 W scenario.)

Get A Battery

So what is the cheapest way to get this done? Let’s take a look at using a deep-cycle battery. Walmart has an RV/Marine battery for $75, rated at 101 AH. Assuming 12 A of current, this battery would support about 8 hours of radio operating. This is going to be way short of the 24 hour operating period of FD but it might be enough to support a less intense operation.  We could also do some things to stretch out the battery life, such as reducing our transmit power. Dropping to 50 W would roughly double the operating time to 16 hours, which should be enough for a single-operator station.

Of course, another option is to double the battery capacity by using two batteries. These amp-hour ratings on batteries are always a bit idealistic and our transmit duty cycle might be more than 50%. Let’s assume we buy two batteries to give extra margin and allow us to run 100W. We will also need a simple charger, which costs about $25. So there you have it, 2 x $75 plus $25 = $175 for a decent emergency power source.  (If we decide to use only one battery, the cost drops to $100.)

Now $175 is a significant investment and only you can judge how well your ham radio budget can support this. For many people, this is affordable and the real question becomes is this how you want to spend my hard-earned cash.

This is my best shot at a low-cost emergency power source. Do you have a better idea?

73 Bob K0NR

Update 25 May 2020: Various people have pointed out that your vehicle is a good emergency power source. You can either run your transmitter directly from the vehicle battery or use the vehicle to charge a separate battery.

Troubleshooting a Radio Interference Problem

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I recently encountered a problem when using my Yaesu FT-950. Sometime during the CQ WW WPX Contest, I noticed an annoying tone (“a birdie”) in my receiver. I’ve had this radio for many years, used it quite a bit and this was the first time I encountered this problem. It struck me as very odd because it did not go away when I disconnected the antenna and it did not change frequency when I tuned around.

I immediately had visions of needing to tear the radio apart or send it back to Yaesu for repair. Instead, this happened…

When it comes to troubleshooting problems, it usually pays to fiddle around with it and see what happens.

Aiwa Six-Band Radio Flashback

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Normally, I avoid posting items of a nostalgic nature, preferring to keep moving forward and not getting stuck in the past.  I am going to make an exception today because I stumbled across some photos of my first radio receiver that went beyond the standard AM/FM broadcast bands.

Aiwa AR-158 radio
This Aiwa AR-158 six-band receiver covered AM, FM, Marine Band (1.6 to 4 MHz), Shortwave (4 to 12 MHz), VHF1 (110 to 136 MHz), VHF2 (148 to 174 MHz).

Aiwa AR-158 Radio

As a kid, I remember saving up my money and buying this radio from the local “dime store” about 3 miles away from my house. It was a 6-band radio made by Aiwa, not a very common brand. I am not sure of the exact model number but it was probably the AR-158.

Of course, the radio had the standard AM and FM broadcast bands, but the real fun came from the other bands. The  “Marine Band”,  1.6 to 4 MHz, picked up some shortwave broadcast stations. The “Shortwave Band” covered 4 to 12 MHz, allowing me to listen to broadcast stations from around the world. The VHF1 band covered the aircraft band from 110 to 136 MHz. I probably did not realize it at the time but the radio must have selected AM for that band. The VHF2 band provided FM reception from 148 to 174 MHz.

Top view of the Aiwa six-band radio.

This receiver gave me my first experience with the wonderful world of radio. My best buddy, Denny/KB9DPF, bought a similar radio about the same time, so we were always comparing notes on what we heard: Radio Netherlands, Deutsches Welle, BBC London, Voice of America, Radio Moscow, Radio Havana, Radio Johannesburg and more. We both installed wire antennas in our attics to see if we could improve our reception.

Sometimes I would hear SSB ham stations but they just sounded like Donald Duck on the AM receiver.  I remember stumbling upon the signal from WWV and wondering what this ticking clock signal was all about. Whatever it was, it was really cool.  (Yes, I listened to it for hours. Just because.)

The VHF Bands

The VHF aircraft band was fun to listen to, although the transmissions were short. I don’t remember if I could hear the control tower from the local airport (probably not) but I could receive aircraft transmissions. The VHF2 band was very interesting and probably planted the seeds for my interest in VHF. I could listen to the local police and fire radio calls.  Tuning was a bit tedious because the receiver had an old-school analog VFO. No digital synthesis on this radio.

The radio picked up the 2-meter ham band, so the actual tuning must have been a bit lower than 148 MHz.  Hearing hams chat on the local 2m repeaters got me thinking about getting an amateur license. This receiver did not have a squelch, so listening to two-way FM signals was filled with lots of receiver noise!

Have Fun

Even back then (in the 1960s), this was not a great radio receiver… imprecise tuning, no squelch, limited shortwave coverage. By today’s standards, it’s even worse. But I had a boatload of fun playing around with it and exploring the radio spectrum. So maybe that’s the thing to be learned from this story:

Whatever radio equipment you have, use it.
You can probably have a lot of fun.

73 Bob K0NR

Your First (and Second) Ham Transceiver

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We recently completed a Technician License class that produced a herd of new ham radio licensees. This always leads to a discussion of what radio should I get? Often, this is centered on the idea of getting a handheld VHF/UHF radio to get started. That is a good first move. However, for many new hams it is worth looking ahead a bit to potential future purchases.

Handheld Transceiver (HT)

Let’s start with an HT. Even if your ham radio future is going to be on the high-frequency bands, an HT is a useful tool to have. After all, FM VHF is the Utility Mode for ham radio. Many new hams opt for an inexpensive Chinese radio such as the Baofeng UV-5R. Recently, I’ve been steering them toward the slightly more expensive Yaesu FT-4XR (around $70).

Yaesu FT-4XR hanheld transceiver
A basic handheld radio.

It is a significantly better radio than the UV-5R but still affordable. Some new hams decide to spend more on an HT, which is also a good option. There are many radios to choose from in the $150 to $350 range.

For hams just interested in local (perhaps emergency) communications, this might be the only radio they get. If it meets your needs, that’s just fine.

FM VHF/UHF Base Station

Another option to consider is to set up a more capable station at your home, focused on FM VHF/UHF operating. This is probably going to be a dual-band radio that covers 2 meters and 70 centimeters, FM only. One way to do this is to use a mobile transceiver powered by a DC power supply and connected to an external antenna on the roof.

FM VHF base station
A mobile transceiver deployed as a base station.

With higher power (50W typical) and a good antenna mounted in a high location, this type of station has better range than an HT. See A VHF FM Station at Home and Considering a VHF/UHF Antenna For Your Home.   This could be your first radio but why not have an HT in your toolkit?

The All-Band Base Station

Many new hams have their eyes on working distant stations via the high-frequency bands. For many people, this is what ham radio is all about. (Honestly, you’re going to need your General license to really participate on these bands.)

Yaesu FT-991A transceiver
Yaesu FT-991A all-band transceiver

The equipment manufacturers have developed the Do Everything Transceiver that covers 160m though 70 centimeters in one box. (Well, they do leave out the 1.25m band which is lightly used in North America.) The leader in this category is arguably the Yaesu FT-991A. This type of rig has the advantage of providing all modes on all bands, including SSB on 2 m and 70 cm. While most VHF/UHF activity is FM, SSB (and CW) can be a lot of fun.

Setting up operations on multiple bands will require some additional antennas. This can be a deep topic so take a look at this introductory article to understand it better: Antennas…How Many Do I Need?

Two-Radio Base Station

Another approach that many hams adopt is to build their home station around two radios: a 2m/70cm radio to cover local communications and a high frequency (HF) radio for the lower bands.

The 2m/70cm radio is the same idea as the FM VHF/UHF Base Station mentioned previously.  It is really handy to be able to leave this radio on your favorite 2m frequency while still having another radio available to operate HF. Compare this to the All Band Transceiver approach which can normally only receive one frequency at a time.

A very popular HF radio these days is the ICOM IC-7300. Like many HF rigs, it covers the HF bands of 160m through 10m AND tosses in the 6m band, too. Recall that 6 meters is actually a VHF band but the general trend is to include this band in HF rigs.

ICOM IC-7300 HF transceiver
ICOM IC-7300 HF plus 6m transceiver

The Mobile Station

Another popular operating style is to have a transceiver in your vehicle. Because our society is so mobile, this approach can be very compelling. This might just be an HT that you take with you when mobile. The rubber duck antenna might be sufficient but an external (magnetic mount?) antenna can really improve your signal.

Many hams install a VHF/UHF FM transceiver in their car. This provides a more capable station (more power, better antenna) when mobile and it’s always there for use. Again, this will probably be a 2m / 70cm radio that operates only FM, the most common mobile ham station.

Some folks set up their mobile station to include HF operating. This is one way to sidestep HF antenna restrictions at home and it fits into our mobile society. There are Do Everything Transceivers that come in a mobile-type form factor. The Yaesu FT-857D is a popular mobile radio that covers HF, 6m, 2m and 70cm in one rig.

Yaesu FT-857D mobile transceiver
Yaesu FT-857D all band mobile transceiver

General Progression

You can see that there are some paths that hams tend to follow in terms of equipment. What you decide to do is going to depend on your interests and budget. Of course, when you are first starting out you may not know what part of ham radio is going to be your favorite and your approach may evolve as you gain experience.

A good first, affordable step is getting an HT. This puts you in touch on the air with the local amateur radio community. It is clearly a VHF/UHF FM play which aligns well with your Technician operating privileges. You can choose to expand on this general direction by adding in an FM VHF/UHF Base Station,  an All-Band Base Station, or a Mobile Station.

If you are interested in using the HF bands, then think about either the All-Band Base Station or the Two-Radio Base Station. Again, obtaining a General class (or Extra class) license is going to be important for HF.

I’ve tried to keep this discussion focused on newly licensed hams. As you gain experience, you’ll find all kinds of other operating activities that are available to you. Sometimes these can be supported by the equipment described above…sometimes you’ll need to purchase additional gear. I’ve mentioned specific radio models that I have experience with but there are many others to choose from. Take a look at the eham.net product reviews to see how well other people like a particular radio.

73 Bob K0NR

What About the Yaesu FT-4XR?

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The Baofeng UV-5R established a new price point for an entry-level handheld transceiver and quickly became the “easy choice” for a newly licensed Technician. It is a very impressive piece of technology for the money (about $30).

However, it is well known that the UV-5R struggles to meet the FCC Part 97 emission requirements. The ARRL lab has published the results of testing a large number of the Baofeng radios and many of them do not meet the FCC spec. Also, the receiver performance is not that great, primarily with respect to adjacent channel and out-of-band rejection. In other words, it is easily overloaded by strong radio signals.

In response, Yaesu created a low-cost radio using similar technology as the UV-5R but with (supposedly) higher quality. This radio escaped my attention when introduced but some recent reviews caught my eye.  In particular, the QST review of the radio includes a detailed lab test report. (The ARRL does a good job with these test reports.)  The review basically says that this radio performs well, especially considering its price class. The price of the radio is currently about $70, so it is more expensive than the UV-5R, but under $100.

Evaluating the FT-4XR

So I went ahead and purchased an FT-4XR to try it out for myself. The main question on my mind is should I recommend the FT-4XR as a good choice for a new radio amateur. I am a license class instructor for our radio club (W0TLM), so I often encounter new hams that are looking for advice on what radio to buy.

My general impression of the FT-4XR is that it looks and feels like a quality product, giving a better first impression than the Baofeng. It fits nicely in my hand and just felt good.

The usability of the FT-4XR is on par with the Baofeng, but a notch down from something like a Yaesu FT-60. In particular, the FT-4XR loads up the keys with multiple functions: press quickly for one function, press and hold for another function, use the “function shift” key for a third function. Yikes! None of this is labeled so you have to memorize all of this or carry a quick reference card with you. Not a huge problem because these are mostly features that are not used frequently or maybe not at all. This means that the FT-4XR is a radio that needs to be set up via programming software to get the desired memories in place. Then, you just choose the right memory / channel.  Not any worse than the Baofeng and similar to many, many radios on the market these days.

The standard FT-4XR manual is adequate but not great. There is an “advanced manual” available on the Yaesu.com web site that may help. The USA version of the radio does not allow transmit outside of the ham bands. This is probably a good thing, especially for a new user. Some people may see this as a disadvantage compared to the Baofeng, which usually transmits over a wider range of frequencies.

Transmitter Harmonics

I trust the ARRL lab tests but I wanted to measure the transmitter to see the harmonic performance up close and personal. The spectrum analyzer measurement below shows the transmitter with very clean harmonics on 2m, just as I would expect from Yaesu. If you look carefully,  you can see a tiny third harmonic just poking up out of the noise floor. (Sorry about the poor graphics, I just took a quick photo of the screen using my phone.)

Spectrum analyzer measurement of a 146 MHz signal shows very clean harmonics, <-60 dBc.

The 70 cm harmonic performance is also very solid, as shown below.

The harmonic content of a 446 MHz signal, very clean, <-60 dBc.

I also checked the power output, transmit frequency, FM deviation and receiver sensitivity on both bands. Very solid performance. Again, nice job, Yaesu!

Yaesu Inconsistency

One thing I found disappointing is that the radio operation and accessories are not consistent with other Yaesu radios. I’ve got a decent collection of Yaesu handhelds, speaker/microphones, antennas, programming cables, etc. None of these work with the FT-4XR.  In particular, the FT-4XR uses the male SMA connector (same as Baofeng) and requires a new type of programming cable. However, for the first-time buyer, this doesn’t matter and it is no different than buying a Baofeng.

Other Reviews

Some other reviews that you may want to consider:

Patrick WD9EWK wrote this article about the FT-4XR, with an emphasis on working satellites.

Recommendations

Back to the main question:

Do I recommend the FT-4XR as a good choice for a new radio amateur?

The answer is YES, this is a better radio than the Baofeng UV-5R and it actually meets FCC Part 97 requirements. If you are considering the UV-5R, scrape up a few more bucks and get the FT-4XR.

If you want an even better radio, I’d suggest moving up to something like the tried and true Yaesu FT-60, about $160. It has a more robust receiver and is easier to use.

VHF/UHF Omni Antenna for SOTA Use

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For Summits On The Air (SOTA), I’ve been using just the VHF/UHF ham bands, with the 2m band being the most popular. For most activations, I use a 3-element Arrow II yagi antenna that has a gain of about 6 dBd. Sometimes that extra gain makes the difference between completing a contact or not.

Omnidirectional Antenna

RH770 dualband antenna
The RH770 Dualband Antenna with BNC Connector

But it is also handy to have an omnidirectional antenna that is easy to deploy. Sometimes I’d rather just call or monitor using an omni without having to point the antenna. “Easy and good enough” can be an effective strategy for SOTA.

A key advantage to an omnidirectional antenna is that it is always pointed in the right direction.

I usually carry one of the TWAYRDIO RH770 VHF/UHF antennas for use with my 2m/70cm handheld transceiver. Despite its low cost, I have found that its performance to be quite good. That antenna is offered with a variety of connectors, including a BNC.

This led me to the idea of putting together a simple antenna mount with a BNC on it, attach an RH770 antenna to it and support it using some kind of pole. I have several monopod devices (intended for use as a camera support) that use the standard 1/4-20 thread. I also have a trekking pole that has the same camera mounting thread. Another option is to use an actual camera tripod which is a bit bulky but may work for some SOTA activations.

After a short visit to the hardware store, I selected crossbar for mounting a light fixture that was about the right size and shape. I happened to have a bulkhead-mount BNC-to-BNC connector which I inserted into the large hole in the crossbar. That hole was not quite large enough for the connector, but a few minutes work with a round file solved that problem.

After some filing to expand the hole, the bulkhead BNC connector (female-to-female) was inserted into the main hole in the crossbar.

The crossbar was originally flat but I bent one one end of it 90 degrees, with the idea that this might offer other mounting configurations in the future. For example, I might be able to strap or tape the 90 degree angle member to a pole or support.

The monopole support is inserted into one of the slots of the crossbar. Again, some filing was required to make the slot big enough for the 1/4-inch thread.

The other end of the crossbar has a large slot that accommodated the 1/4-20 mounting stud. Actually, the slot was not quite wide enough, so some addition work with a round file opened it up. I secured the 1/4-20 thread using a nylon wing nut.

A nylon wing nut (1/4-20 thread) is used to attach the crossbar mount to the monopod.

I’ve used this setup on one SOTA activation and was pleased with the results. I carried the crossbar mount attached to the monopod in my pack. On the summit, I simply installed the RH770 antenna onto the top BNC and extended the monopod. On this summit, I found the perfect pile of rocks that made a good support for the monopod. Then I used a short length of RG-8X coax between the bottom BNC and the 2m/70cm transceiver.

The antenna support in use: the RH770 antenna attaches to top BNC connector, the crossbar mount attaches to the monopole which jammed into a pile of rocks on the summit. An RG-8X coaxial cable feeds the antenna through the bottom BNC connector.

Although my primary interest was with the 2 meter band, it was really convenient to have both 2m and 70cm on the same antenna. I am pleased with operation of the antenna and the ability to deploy it quickly. I expect to carry this on most of my SOTA activations.

73 Bob K0NR