Category Archives: VHF/UHF

One of my toys these days is a Jeep Wrangler (TJ) which we use for playing in the mountains. I finally got around to installing some ham radio equipment in it a few weeks ago. I mostly wanted to have good old 2 Meter FM – the amateur radio utility mode – in the vehicle. These days, it makes sense to include 70 cm (440 MHz) as well.

The first priority was to pull the old AM/FM receiver and put in a new Sony CDX-GT430. Crutchfield supplied excellent installation instructions and soon I had the center portion of the Jeep dash pulled out and the receiver installed. This work gave me valuable experience in pulling the Jeep’s dashboard apart. Not surprisingly, the Wrangler disassembles quite nicely with just a few screws here and there and a handful of those snap-in-place trim fittings to undo.

The next job was to get a dual-band Yaesu FT-7800R 2M/70 cm transceiver installed. This is a one-frequency-at-a-time dualbander, very easy to use with all the required FM features. Originally, I thought I would just bolt the unit down in a convenient spot and call it good. As I surveyed the Jeep, I realized that I could do much better using the detachable control head approach (using YSK-7800 separation kit). The control head was mounted to the main plastic piece that covers the center of the dash using a pair of angle brackets from the hardware store. The radio box went under the back seat… somewhat protected from weather when the top is down and definitely not in the lower part of the Jeep floor. With the hardtop off, a hard rain can cause a small lake to accumulate inside the Wrangler. (I know from experience.)

The most challenging decision turned out to be what antenna to use and where to put it. Mobile antennas are always a trade off between radiating effectiveness, ease of installation and overhead clearance. The Wrangler has a removable hardtop, made of fiberglass. This presents two problems: the fiberglass makes for a lousy ground plane and there will be times when we go topless. So a roof mount was not looking very attractive. Another choice was on the spare tire mount, which hangs off the back of the vehicle.  I’ve seen a few installations like this that look good. It looked like a more complicated installation and I was not sure how well the antenna would radiate off the back of the vehicle.

In the end, I chose to mount a short dual-band antenna on the hood near the driver’s side, using an NMO-style mount with one of the L-shaped trunk mount brackets. This is not the best location for antenna efficiency but it would be “good enough” for most use. The antenna is a 1/4-wave on 2 Meters, about 19 inches long, also tunes to 70 cm. The low profile has the added advantage of not getting pounded down by tree branches on the back roads. And I can take the hard top off without changing the antenna configuration. Did you spot the antenna in the first photo?

The Jeep had a obvious rubber plug that I poked through to get the DC power and antenna connections through the engine firewall. Per the usual guidance from the transceiver manufacturer, I connected the power cable directly to the 12-volt battery (with fuses in line).  The antenna seems to pick up a bit of ignition noise due to the close proximity to the engine, but it is tolerable.

Off to the mountains to have fun.

73, Bob K0NR

Activity was light during the ARRL January VHF Sweepstakes, but I had fun anyway, working more grids on 2 Meters than I expected. The January VHF contest is not a big deal for me but I try to at least get on the air. In previous years, I have operated backpack portable for the contest.

This year, I was up at our cabin near Trout Creek Pass in the western part of DM78. The cabin sits at about 9500 feet in elevation with a good radio horizon in most directions. It is blocked a bit to the west due to some 14,000 foot mountains. I don’t have serious antennas up there (yet), so I decided I would just temporarily install a 2 Meter yagi and focus on working that band. (I am thinking I need to get serious about 2M VUCC.) The snow can be quite deep so I wasn’t sure that I could get the SUV up the driveway. Since we might have had to carry everything up on snowshoes, I was thinking minimal equipment. (It turns out the neighbor with a frontloader cleared the driveway, so this was not a problem.)

The rig is a Yaesu FT-847 (one of my all-time favorite rigs) that puts out 50 Watts on 144 MHz. I probably should have brought my Mirage amplifier along but, again, I was going for minimal equipment. With only one band to worry about my operating focus was, well, only on one band. This basically meant hanging out on the calling frequency (144.200 MHz) listening for activity and making calls. During other contests, I’d be jumping around from band to band, trying to make sure I didn’t miss anyone. The one band approach certainly is simpler…perhaps a bit boring.

I was careful to set up my station for both SSB and CW modes. In previous contests, I’d forget about CW until I really needed it….then scramble around for my keyer, frantically trying to plug the right cable into the right jack and get it all working.  For CW, I had my XT-4 CW Memory Keyer, which is a simple, but effective 4-memory keyer. I loaded up the first memory with a “CQ CQ CQ de K0NR” message. The second memory was loaded with “R R R DM78 DM78″….which sends my vhf grid to the other station. The third memory is used for calling a specific station. I manually send the other stations call sign, then punch the third memory “de K0NR K0NR DM78 DM78”. The fourth memory is to acknowledge that the contact is complete: “QSL QSL 73 de K0NR K0NR”.

I put the 2M9 Yagi from M2 on a TV mast strapped to the front deck of the cabin. There was very little wind so I didn’t bother to guy the mast, but I did take it down at night in case the wind came up.

Most of the stations I worked were in my grid and DM79 (greater Denver).  I made only 20 Qs but picked up 9 grids (DM68, DM69, DM78, DM79, DN70, DN80, DM89, DM98 and EM09). This is a rather high grid/Q ratio and I felt like I did pretty well in terms of picking up the available grids.

I worked N0KE over in the western part of the state in DM69. On this path, some of the adjacent mountains get in the way. I heard Phil calling on CW on 144.200 MHz and worked him on that mode. I doubt that we would have completed the contact on SSB. CW really does get through when you are operating near the noise floor. I also managed to snag N0LL over in EM09 Kansas using CW. I have worked Larry in the past on 2M from other locations but not from this far west. I figure that he is about 390 miles away from the cabin….not bad for 50 Watts on 2 Meters. Of course, Larry has an awesome station on VHF and puts out a big signal. My wife Joyce K0JJW did an impromptu rover run over to DM68 (about 6 miles away) to activate that grid. Another nice surprise was finding KI0SK out roving in DN80 and DM89. Those are relatively rare/unpopulated grids so the only way they get activated is via a rover station.

So my summary is a poor showing on number of QSOs but pretty decent on number of vhf grids. And a weekend in the mountains messing around with ham radio is always a good time.

73, Bob K0NR

Just a reminder that the January VHF contest is this weekend, starting at noon on Saturday Mountain time. I will be at our cabin up in the mountains (DM78av) with no real antennas up yet but I’ll have a decent Yagi set up temporarily for working 2 Meters. I’ll listen on the calling frequency 144.200 MHz for SSB contacts (if it gets busy, I’ll move up to 144.220 MHz). I’ll also have a radio listening on 147.42 MHz for anyone working FM. (Use of 146.52 MHz is prohibited for contest contacts. Dumb rule, long story.)

This is a great opportunity to try out weak-signal VHF since there will be stations on working the contest. See the contest rules on the ARRL web site.  If you are new to VHF contests, see my page: How to Work A VHF Contest.

73, Bob K0NR

I was looking out the window the other day and noticed that my wire HF antenna is laying on the ground. Hmmm, probably doesn’t radiate very well that way. But if I put a long, lossy coaxial cable in line, the SWR will still be good at the transmitter. And I can tell my buddies that it works just fine because “I can work everyone that I hear.” (What a dumb thing to say 🙂 )

This made me realize that most of my ham radio activity lately has been on 2-Meter FM. Actually it has been on 2M and 70cm FM, as I tend to lump these two activities together. These days, my VHF/UHF FM rigs have at least 146 MHz and 440 MHz in them (FT-7800, FT-8900, etc.). I cruise down the road and flip on the rig, talk to the locals, talk to the XYL, etc. It is just too easy and too convenient. It fits the mobile lifestyle, whether it means operating a mobile rig in the car or grabbing an HT to take along on a business trip. (I used to run HF and SSB VHF mobile but found that the rigs were rarely used, so I removed the gear from my vehicle.)

Of course, I need to apologize to the rest of the ham community for this failure to act according to accepted social norms. You know how it is…Real Hams operate HF, weak-signal VHF, microwaves, etc……almost anything that is not 2M FM. Every so often I hear that comment about “well, those techs just hang out on 2M FM,” implying that those guys are permanently stuck in ham radio middle school, unable to graduate to the next level. Or sometimes the FM operators are referred to as having “shacks on the belt” which are dependent on the “box on the hill.” The main message is that 2M FM is just too easy, too plug-n-play, too much like an appliance….too convenient. We certainly can’t have that!

Don’t get me wrong…I enjoy HF, DXing, contesting, digital modes, almost anything to do with amateur radio. That’s the cool thing about the hobby…so many bands, so many modes. One of my favorite activities is operating the major VHF contests. (I’ve even been known to work a few CW contacts.) But on a day-to-day basis 2M FM just seems to fit in better.

Some people call 2M FM the Utility Mode, because it is the mode that gets the job done. Last week, we had a weather net activated to track thunderstorms and a few tornadoes. Did this happen on 40M? I don’t think so. Two meters carried the load. Where do most of the ARES and RACES nets meet? Two meters. How is most public service communications handled? Two meter FM. Even some hard core HF DX enthusiasts are known to flip over to 2M FM to tell their buddies that the DXpedition to a rare country is on the air. It is the Utility Mode.

Over the weekend, I was driving through the mountains and heard an aeronautical mobile working stations simplex on 146.52 MHz…lots of fun. Another time, I heard a station calling about 80 miles away (I was in a high spot) and I had the pleasure of making that contact….again, on 2M FM. A few weeks ago, I operated in the Colorado 14er Event from the summit of Pikes Peak. Since many of the mountaintop stations had hiked up, the most popular mode of the day was (you guessed it) 2M FM.

So sorry, I have been hanging out on 2M FM. I’ll try to get that HF antenna back in the air one of these days.

73, Bob K0NR

It didn’t start out all that great. First, my boss decides that I need to be in Scotland the week before the contest weekend. I have nothing against Scotland, I just preferred to not be there right before the biggest VHF contest of the year (ARRL June VHF QSO Party). I needed to be home putting together antennas, repairing cables, loading software, etc. ahead of the contest weekend.

At the last minute, I piled all of the gear (well, most of it) into the SUV and we head to the mountains. I planned to set up my portable station at our antenna-less cabin in the western part of grid DM78. (Gotta get that tower up for next year.) My station consisted of an FT-847 on 2M and 70 cm, driving decent yagi antennas on those bands. On 2M, a linear amplifier boosted the output to 170W, so I had a decent signal on that band. For 6 Meters, I used an FT-100 running 100W to a 3-element yagi and on 222 MHz I just had an ICOM FM transceiver feeding a small yagi.

I downloaded N1MM logging software at the last minute and attempted to install it on my new Windows Vista PC. Turns out that Vista doesn’t seem to like N1MM or vice versa. (I am bumping into this on occasion where some software aps are not fully checked out on Vista.) I bailed on N1MM and grabbed VHFLog by W3KM. It was the first time I have used it but it worked well for me.

There was very good sporadic-e propagation on 6M for a large portion of the contest, occasionally extending to 2M. This is the way the June contest is supposed to be! Six meters kept me quite busy and I am sure I missed some good rover contacts on the other bands. This is the downside of a single-op station when six is open. Most contacts were on SSB but I did use CW to grab a few grids on 2M and 6M (N0KE in DM69 and K0YW in DM67). Wow, my CW is getting rusty and it was tough going but I made the contacts.

I had 206 contacts on 6M, which I thought was quite good until I saw some of the other guys scores on the local email reflector….many of them did a lot better. Worked XE2YW in Mexico and a number of VE’s in Canada. I was happy with the 15 grids on 2M, including a new grid via sporadic-e (W4VC EM81). I snagged KB0HH up in EM06 and N0YK in DM98.

Band       QSOs X pt =  QSO pts.  X   Grids   =     Points
---------------------------------------------------------------
50         206    1      206           125           25750
144        34     1      34            15            510
222        1      2      2             1             2
432        12     2      24            6             144
---------------------------------------------------------------
TOTALS     253           266           147           39102

                                         Claimed score =  39102

This contest has reinforced the notion that for me, VHF is all about 2M and 6M. The Magic Band provides the excitement and 2M provides the challenge (with enough local activity to keep some interest going). The practice of moving on up to 222 MHz, 432 MHz and higher and just working the same guys over again doesn’t seem as much fun. It definitely generates contest points but I am thinking more about VUCC and grid chasing. I will be optimizing my station to do better on 2M and 6M….upgrade the antennas, amplifiers, transceivers, etc.

73, Bob K0NR

As reported on the ARRL web site, the FCC rejected the proposal from Ken Chafin, W6CPA, and Leon Brown, KC6JAR to create a 2M subband for digital voice repeaters. This proposal was apparently a good-intentioned approach to opening up new spectrum for digital machines (D-STAR, P25, etc.). Chafin and Brown jointly filed a PRM in October 2007 requesting that the FCC “propose to expand the frequencies on which an amateur station operating as a repeater (repeater station) may operate,” specifically Section 97.205(b) to allow repeater stations to transmit in the 145.5-145.8 MHz frequency segment of the 2 meter amateur service band.

The FCC correctly rejected this proposal, indicating that the Amateur Radio Service does not need additional 2M spectrum for repeaters. Also, the FCC rejected the notion of a subband that is dedicated to a particular modulation format.

I appreciate the problem of trying to open up repeater frequency pairs for digital voice repeaters. We are struggling with that issue here in Colorado. It seems that all of the 2M repeater pairs are “full” in the front range. (Full but not necessary well-used.) The Colorado Council of Amateur Radio Clubs (CCARC) took action to open up digital voice repeater pairs on the 440 MHz and 1.2 GHz bands, but we haven’t figured out what to do on 2 Meters.

Technically-oriented hams want to put up repeaters using the new digital technology, so we want to find a way to support that effort. One answer is to expand the repeater subband. But let’s be honest….in most locations the 2M repeater subband are filled with repeaters that largely sit there doing nothing. I find it very difficult to justify adding additional spectrum to amateur repeater usage.

Also, what is the big freaking deal with 2 Meters? Why does everyone insist on having a D-STAR machine on 2M? There is generally much more room on 70 cm (440 MHz), so let’s give that a go. I think the ham community is stuck in the 2-meter rut. (I understand this, sort of, for good old FM, but digital voice means buying new gear, so let’s do it on 440 MHz.)

73, Bob K0NR

Colorado just experienced a nice 6M sporadic-e opening. Phil N0KE sent out this article as encouragement to try 6 Meters.

A few years ago we started seeing new HF rigs with 6 meters included, and at the 100 watt level in many cases. At the Central States VHF Conference in July 1998, it was claimed that world wide there are now 30,000 more stations with 6 meter capabilities. In the ARRL June 1998 VHF contest, several stations exceeded 1,000 QSOs on 6m and about half the all time top QSO totals were made this year, which would indicate a lot of these rig owners are using them on 6m.

You may have an existing antenna that will function on 6m. Obviously the best thing to do would be to put up a 6 meter yagi and an advantage is that they are small and light and you may be able to add it on an existing tower. For those who want to try out the band without making the commitment for buying a new antenna, you may be able to use an existing antenna. Most 15 meter antennas will work reasonably well on 6 meters. My TA33 tribander loads well. I’ve also tried the TH6DXX, TH7DXX tribanders and KLM 6 element 15 meter monobanders on 6 meters with reasonable results. You may have to use a tuner to get full power. I’ve found that a HF tuner in the 10 meter position will often work and the auto tunners in many rigs will work too. There are some inexpensive 6 meter antenna tuners made. A multi band vertical that covers 15 meters will also work, except one gentleman told me he fried the 15 meter trap on his R7000 in a matter of seconds at the 100 watt level on 6 meters. I’ve had good luck using a Butternut HF6V and HF9V on 6m. Most HF SWR and power meters are still reasonably accurate at 50 MHz. I’ve also worked some other stations using unusual antennas on 6 meters. I worked a New Zealand station who was using 10 watts to an 80 meter folded dipole. A 2 meter 5/8 wave vertical is very close to a ¼ wave on 6 meters and lots of people have used that mobile or like the guy in Dallas I worked who was using one on a magnetic mount on his bath tub. I never did find out why he was using the bathroom for his ham shack.

Since many of these HF+6 rigs, like the Icom 706 are very small, they are very attractive to take on that contest or vacation trip, especially when coupled with one of the light weight switching power supplies that will convert a wide range of AC voltages to 13.8 VDC. I easily carried my rig, power supply and laptop as carryon luggage on a KH6 trip for the 1997 CQWW SSB. You may end up in a country with little or no resident 6 meter activity and be much more in demand than on any of the HF bands. You can make some 6 meter QSOs even without packing along a 6 meter yagi, but do take the yagi if you can.

On 6 meters 50.000 to 50.100 is reserved for CW and contains many beacons. US beacons are mostly between 50.060 to 50.090. Most DX CW QSOs take place between 50.090 and 50.100. 50.100 to 50.125 is the DX window in the USA with 50.110 being the international DX calling frequency. In Europe the DX window is 50.100 to 50.130. The USA domestic calling frequency is 50.125. In Europe the domestic or inter Europe calling frequency is 50.150. Six meters is like other VHF bands in that SSB and CW are used in the same portions of the bands. Experienced expeditioners like W6JKV will constantly switch back and forth from CW to SSB on the same 6 meter frequency. Cross mode QSOs are also common.

We are in the spring sporadic E season that runs from mid May to late July or early August. Whether you are doing E mail or watching TV etc turn the rig to 50.125, turn up the squelch. If anything is happening, you will most likely hear it first on 50.125. Once the band is open move above the calling frequency for QSOs. I’ve found activity up above 50.250 on good openings. Another clue is if you are hearing very strong E (short) skip on 10m, chances are very good that 6m is open in the same direction. E skip is typically between 700 and 1400 miles per hop. Double hop is fairly common and multi hop propagation of 4 or more hops is much less common. Last June I worked 27 JA stations one evening and two days later I worked 7 European stations. both of these openings were probably 4 or 5 hops. Generally you need a good gain antenna and power but a few Colorado stations did work the JAs and Europeans with 100w to good antennas last summer.

73 Phil N0KE

The March issue of QST arrived in the mail today, so I sat down and did my usual browsing through it. Ah, the September VHF contest results article by Sean KX9X is in here. The September contest is not a focus for me….usually I am out of energy for serious VHF contesting after participating in the June ARRL contest, the July CQ VHF contest and our local mountaintop event (Colorado 14er Event) in August. More to the point, propagation is usually not that great in September in Colorado and not that many VHFers participate in the contest (compared to the June event).

Just as surprising, this outstanding effort resulted in a first place score for my category in the Colorado Section, Rocky Mountain Division and the entire Midwest Region. Talk about taking names and kicking b***t!

In the article KX9X wrote:

In what may be the the most concentrated effort in history, Bob, K0NR, needed only five minutes’ worth of operating time to capture the QRP Portable category in the entire Midwest region!

Oh, I guess I should say that there was only one other entry in the category: N0JK submitted another Single Op Portable log with a score of 9 points. So the competition was not that intense.

Well, I guess you never know how it will turn out. So get off the couch, turn on the radio and work someone this weekend.

One of the local clubs recently had a heated discussion about the use of the National Simplex Calling Frequency, which is 146.52 MHz in the US (per the ARRL band plan). You have probably heard the argument before…..is the calling frequency reserved to just calling or is it OK to ragchew on that frequency?

In the Summer 2006 issue of CQ VHF, I wrote about mountaintop operating and included these thoughts on the use of 146.52: