Category Archives: RFI

RFI on SOTA Summits

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One thing to watch out for when doing SOTA activations is the presence of strong Radio Frequency Interference (RFI) on some peaks. The typical scenario is that the summit is also an established radio site with transmitters that interfere with your ham radio operations.

Bob/K0NR checking out the radio gear on Mount Bailey (W0C/FR-062).

I use the VHF/UHF bands for SOTA, so I am writing from that perspective. My impression is that HF interference is much less likely because these radio sites don’t usually have any HF transmitters. However, they may have broadband noise sources such as networking equipment, power line arcing or switching power supplies that can create problems on HF. Anyway, this post is focused on 2 meters and higher bands.

In my experience, the transmitters at radio sites may include land mobile repeaters (VHF or UHF), NOAA Weather (162.xx MHz), TV/FM broadcast stations and mobile wireless (cellular) systems. The TV/FM broad stations are really bad news because they run a crapton of RF power.

The worst summit I have encountered is Sandia Crest (W5N/SI-001) near Albuquerque, NM. See trip report here. They even have a sign in the parking lot to warn you that the RFI may wipe out your car’s keyless remote.

Well, this sign did warn me of radio interference at Sandia Crest.

Some other notable RFI-heavy SOTA summits are Monarch Ridge South (W0C/SP-058), Squaw Mountain (W0C/PR-082), Terry Peak (W0D/NW-002), and Greentop (W4T/SU-076).

In a high RFI environment, your radio receiver gets overloaded such that you can’t hear stations calling you but they can hear you just fine. This results in the SOTA activator calling and calling while the chasers get frustrated that the activator never hears their call. Not good. It may not be obvious that this is happening. This blocking of the receiver may come and go, depending on which transmitters happen to be active.

Mitigation Strategies

There are a few things that you can do to deal with the RFI:

Move Away From The Source

Probably the first thing to try is just moving away from the source of interference. This may mean moving away from the highest point on the summit but it may be better overall to give up a few feet of elevation to not have the interference. You’ll need to stay in the activation zone to be a legitimate SOTA activation.

Use A Better Radio

Some radios are better than others when it comes to receiver performance including the ability to reject unwanted signals. The low cost radios from China (Baofeng or similar) generally have lousy receivers so they are a poor choice for operating from an RFI-intense summit. Many people report better results with the Yaesu FT-60, a solid performer. Commerical radios from Motorola are even more robust. I’ve been using a small mobile radio for SOTA (Yaesu FT-90) which outperforms most handheld radios.

Change Your Antenna

Using a directional antenna can help…just point it away from the source of the interference.  Oddly enough, using a worse performing antenna can help improve your ability to communicate. For example, a rubber duck antenna on a handheld radio will allow less of the interfering signal to get into your receiver which may improve your ability to receive. As long as the antenna is “good enough” to complete the radio contact, it may be the way to go. One trick I’ve used is to deploy two radios, one for receive with a crummy antenna and the other for transmit with a better antenna. That way, you still radiate a stronger signal while reducing the interference into the receiver.

Use A Bandpass Filter

You can insert a filter into your antenna feedline to reduce the interfering signal. The best approach is to use a bandpass filter that passes the frequency you are operating on but attenuates other signals.  SOTABeams offers a compact bandpass filter for the 2m band. (Note that it has a 5W power rating which is fine for handheld radios but not more powerful transceivers.) DCI Digital Communications offers higher power filters but they are much larger in size.

Change Frequency

Sometimes a small change in frequency might help a bit if the interference is limited to certain frequencies. Another tip is to try another band. That is, if you are getting interference on 2 meters, you may find that the 70 cm band is better. Or vice versa. It all depends on the transmitters at the site.

73 Bob K0NR

Getting On HF: Some Remedies

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In my previous blog post, I listed four barriers to getting on HF:

  • antenna restrictions
  • radio frequency interference (RFI)
  • cost
  • the fiddle factor.

Fiddle Factor really represents how multiple issues can come together to dramatically increase the complexity of an HF installation.

Now I’d like to propose some ways of dealing with these barriers.

Antenna Restrictions

A lot has been written about this problem and there’s enough material to write a dozen books about this topic. The remedies that come to mind fall into two main categories:

  • Hide your antenna
  • Change your location (temporarily or permanently)

Common strategies for hiding an HF antenna include: attic antenna, low profile wire antenna, flagpole antenna and temporary antenna. I recently came across this fabulous guide to stealth antennas from The Villages Amateur Radio Club. It was developed based on practical experience in an HOA-controlled community. One interesting point they stress is that the mode you use interacts with the capability of the antenna. Simply put, if you are using a compromised antenna then it really helps to use a more efficient mode such as CW, PSK31, JT65 or FT8. Good advice!

I received quite a bit of feedback via twitter that a solution to antenna restrictions is change your location.  One answer is to permanently move your home to a new location, typically out in the country with wide open spaces and no restrictive covenants. This is easy to say and often difficult to do.  I am going to assume that for the most part you are stuck with your home location (for whatever reason) and not spend much time on it here. But keep this in mind when the opportunity to move happens. Every time I’ve purchased a house, I always evaluated the property for antenna options.

Another option is to change your location temporarily, as in portable operation (can you say Summits On The Air?) I like portable HF operating and have operated from a number of islands while on vacation. You don’t have to do a DXpedition, you can always just go to a local park and set up a station there. Heck, you can always “go portable” in your backyard. Set up  a temporary antenna, operate and take it down before anyone has a chance to complain.

Another “change your location” strategy is to use a remote ham radio station. Many clubs have established a remotely-controlled station (usually controlled via the internet) for their members to use. Or you could use one of the commercial remote radio systems (such as Remote Ham Radio).

Radio Frequency Interference (RFI)

RFI generally occurs when a device creates radio frequency energy on frequencies that you want to use.  One very discouraging experience is to turn on your newly-installed HF station to find the ambient noise at S5 across your favorite operating band. Frankly, this can be a really difficult problem to solve. Many books have been written on this topic, too. One of the best is The ARRL RFI Book. The ARRL RFI web page may be helpful, too.

The source of interference is either under your control (something in your residence) or it can be from external sources (your neighbor’s house, the AC power lines, …)  RFI sources are easier to find in your own home. A good first move is to go around and unplug everything electronic in the house to see if the problem goes away. Or you can go through your circuit breaker box flipping all circuits off until the problem disappears. (Of course, you need to keep you HF radio powered up so you can listen for the noise.)

If the problem is outside your home, things get a lot more difficult. You’ll have to track down the source and engage the owner of the device in a conversation about correcting the problem.

If the problem is power line noise, the electric utility is supposed to be able to correct it. However, the technical capability on RFI issues at electric companies ranges from none to quite competent.

Cost

What can we do about the cost of getting on HF? I’d say, not a lot. Your best strategy is to look for used equipment which can be less than half the price of new. However, if you are comparing an HF station to the cost of a $30 Baofeng handheld transceiver, you will probably be disappointed. In my previous blog post, I estimated that a used HF station could be on the air for ~$500.

One comment I received via twitter is that the cost alone may not be the issue. For some folks, the issue is spending that much money and not knowing how much success they will have on HF and whether they will truly enjoy it. Good point. One way to deal with this issue is to operate from someone else’s station to try out HF or to borrow some equipment. This will defer the cost until you know more about HF operating and judge whether it’s right for you.

One idea that might look attractive for saving cost is to buy an inexpensive, low-power (QRP) transceiver. I would avoid that option as it increases the fiddle factor.

The Fiddle Factor

The fiddle factor represents how multiple issues can come together to dramatically increase the complexity of an HF installation. When the complexity increases, the probably of success decreases because there are just more things to go wrong.

So the remedy is to avoid a high-fiddle-factor installation. Ideally, you would use a simple antenna (dipole, end-fed halfwave, etc.) hung in the clear with no obstacles around. Real world constraints may come into play here and require you to make other choices. Just be aware that each complication drives complexity.

Find a Mentor (Elmer)

The one universal strategy for success with ham radio is find a mentor, also called an Elmer. Having an experienced radio ham to answere questions and bounce ideas off of is extremely valuable.

How do you find a mentor? See Dan/KB6NU’s suggestions on the topic. You may have to settle for mentoring via the internet but it is way better to have someone local that can actually see your house and antenna installation options.

Anything else?

Those are my suggestions for how to deal with the barriers of getting on HF. I am sure there are more ideas out there.
What do you think?

73 Bob K0NR

Getting on HF: The Fiddle Factor

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We’ve had a steady stream of new licensees come into our radio club driven mostly by our highly-successful Technician license class. Many of these licensees have gone on to get their General license so they can have fun on the HF bands. I’ve given advice and aid to a variety of people as they get their HF station set up and I’ve come to appreciate that for Average Joe Ham this is a big step. I’ve also noted some recurring problems that get in the way of success on the HF bands, which I’d like to explore here. Recently, I asked my twitter followers for input and got some great ideas from them, too. Thanks!

A basic wire antenna for the high frequency (HF) bands.

Here’s what I came up with as the four main barriers to success on HF.

Antenna restrictions

The first barrier that pops up are antenna restrictions which can come in the form of zoning regulations, protective covenants (homeowners associations), spouse’s opinion, potential objections from neighbors and your own sense of aesthetics.  Any of these can limit the type and size of antennas you can or will install. More to the point, this can be a showstopper for some folks. They may decide that they simply can’t have an HF antenna on their property.

Of course, HF antennas tend to be large due to the longer wavelengths used (compared to simple VHF antennas). But there are some compact antenna designs that use magnetic loops, loading coils, etc.

RFI

The second issue that often pops up is radio frequency interference (RFI) from sources such as power lines and consumer devices. These issues can be very frustrating because you have to do two things: identify the source of the noise and eliminate it. If the problem is power line noise, your local utility is supposed to be capable of finding and correcting the problem. Some are better than others. Consumer devices are a huge problem due to the common use of high-speed digital circuits. If the interfering device is in your home, that makes it a bit easier to deal with…if it’s somewhere in the neighborhood, then its harder to diagnose and fix.

My twitter followers mentioned that solar electric systems often radiate RF energy (and they are a growing trend). Here in Colorado, we are seeing more problems with cannabis grow operations that use RF-ugly industrial grow lights.  But Part 15 consumer electronics are a big and growing problem…too often they are little RFI generators.

Cost

I hesitate to add cost to the list but I do think it’s a factor. A starter HF station costs something like this (your mileage may vary): $750 for a new transceiver (think Yaesu FT-450 class), $100 for a power supply, $100 for wire antenna (homebrew) and coax => ~$1000.  Yes, you can buy used gear and get this cost down…maybe to half ($500)?

Comparing this to a Baofeng HT purchase ($30), it is a lot more money. However, it is on the same level as other significant consumer electronics purchases such as a high end smartphone or mid-range notebook PC. As someone correctly pointed out to me, the utility of a notebook PC is very clear…you will get value out of it…but success with HF is still a gamble. What if you spend $1k on an HF station and never have any success with it?

Fiddle Factor

But I think there is another principle in play here, which I’ll call the Fiddle Factor. Actually this is the interaction of multiple issues.
Let’s start with a close to ideal situation for a first HF station: a simple antenna (perhaps a dipole) strung across a large lot (no space restrictions) with plenty of ways to hang the antenna (let’s assume there are plenty of trees). Oh, and no antenna restrictions.
This is an attractive antenna situation, but you’ll still have to mess around with getting the antenna hoisted, coaxial cable run, SWR checked and the antenna needs to be trimmed. This is one level of Fiddle Factor, call it F.
Now let’s say the lot is not that big and there are only a few supports available to hang the antenna. Now you need to fiddle with the antenna design to perhaps shorten it and compromise how it is being hung. So we have an additional fiddle factor which results in an F2 (or F squared) situation.
Now suppose we decide to use a more finicky antenna design…perhaps a magnetic loop or a multiband dipole. (A magnetic is inherently narrowband, so you have to tune it for the specific operating frequency. A multiband dipole will need to be tuned for each band of operation and they usually interact.) This adds another fiddle factor bring us to an F3 level challenge. Next we consult our homeowners association rules and find out that there are physical restrictions on how we can mount an antenna…and they might be vague and arbitrary. This gets us into F4 territory.
OK, you probably get the idea. My point is that these challenges multiply and interact as you try and figure out an antenna solution. Now you could argue that a VHF installation has similar challenges but I think simple VHF stations inherently have a lower Fiddle Factor. More specifically, a basic 2m/70cm vertical antenna can be small and easy to install without a lot of tuning required.
Now put yourself in the position of a radio ham getting on HF the first time. These issues, especially the fiddle factor, can really get in the way of successful radio operating. In my next post, I’ll look at some ways of dealing with these issues.
73 Bob K0NR

Radio Frequency Interference From 12V-to-USB Adapters

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Many small electronic devices have switching regulators in them that can generate a bunch of Radio Frequency Interference (RFI). This is not my first encounter with RFI-spewing devices. See this article about a automotive 12V-to-USB adapter giving me trouble: This Interference Seems To Follow Me Everywhere

I recently bought a couple of adapters that are physically larger than the one I wrote about. I was thinking that a larger size might allow for a little more filtering and a design that does not radiate. I was half right: one of them works pretty well, the other is an RFI Bad Boy.

Take a look at this short video where I check them out.

 

 

 

This is an Amazon link to the adapter that works pretty well.
Enercell® 2-Port USB CLA Car Charger

 

73, Bob K0NR

SOTA Summit Activation: Sandia Crest (W5N/SI-001)

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Joyce KØJJW and I were headed to the Duke City Hamfest in Albuquerque when we decided to make a side trip up Sandia Crest for a low overhead (read: slacker) Summits On The Air (SOTA) activation.

IMG_3266
The view of the summit when approaching via the Sandia Crest Road.

Sandia Crest pokes up 10,678 feet, towering over Albuquerque at roughly 5000 feet. Although the weather was rainy, we enjoyed the drive up the paved Sandia Crest Road through the Cibola National Forest. This looks like a great area to explore and we’ll probably be back sometime in the future.

At the parking lot, about 40 vertical feet below the summit, we paid the $3 per day use fee (self-service USFS station), grabbed the radio gear and headed up the walkway to the top. There is a gift shop and restaurant at the south end of the parking lot, along with several hiking trails. A large radio site on the north end of the parking lot has numerous towers and high power transmitters. The field strength is so strong that a sign has been placed there to warn of radio interference to car alarms and keyless remotes.

There is a large radio site with powerful transmitters near the summit.
There is a large radio site with powerful transmitters near the summit.

I pulled out the trusty Yaesu FT-60 handheld transceiver with the MJF-1714 1/2-wave antenna for 2 meters. I gave a few calls on 146.52 MHz and heard no replies. I am thinking, “surely with so many hams in town for the hamfest, someone is listening on five two.” Joyce was standing next to me with her FT-60 and a rubber duck antenna. We noticed that her radio was hearing signals that I could not hear.

Well, this sign did warn me of radio interference.
Well, this sign did warn me of radio interference.

Hmmm, the radio with the better antenna is not able to hear anything but the radio with a crummy rubber duck is working fine. At this point, I realized that my HT was being overloaded from the transmitter site with my high-efficiency antenna doing a great job of coupling those signals into my radio. I had to chuckle about this since I’ve often pointed out the poor performance of your typical rubber duck antenna. In this case, the less effective antenna was doing us the favor of reducing interference.

I swapped antennas and began making calls on 2m fm with the rubber duck. I also moved further away from the radio site to reduce the signal level. Yep, now I heard some guys coming back to me on 146.52 MHz. I could tell there was still some interference but it was workable. In short order, I had these stations in the log: KE7WOD, W5AOX, K5LXP, WB5QXD and K0JJW (after moving downhill outside of the activation zone),. Thanks for the QSOs!

I will admit that NM5SW mentioned the interference problems on this peak, so I had fair warning. Keep in mind that the FT-60 has reasonably good intermod performance, probably better than your average HT, and was getting completely blocked with the long antenna. I was glad that I was not using one of the Baofeng HTs. It made me wonder how well my FT-817 would do under the same conditions, but that will be a test for another day.

This sign shows the trail system at the summit and the location of the tram.

Another way to ascend the peak is via the Sandia Peak Tramway, which comes up from the Albuquerque side. We came across this sign that shows the trail system near the summit and indicates the top of the tram (click to expand). The tram drops passengers off some distance from the actual summit, so you’ll have about a 1.5 mile hike to the summit.

In summary, it was a successful activation although the weather could have been better. The big thing I learned was that a more efficient antenna is not always the best antenna. Sometimes a crummy rubber duck does better!

73, Bob K0NR

P.S. I later heard from Mike KD5KC that the Kiwanis Cabin (shown on the map) is a good place to operate from without radio interference issues on HF and VHF.

The Mysterious Case of Alternator Noise

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When I purchased my 2003 Ford Escape, I decided to install multiple ham radios and a bunch of antennas. Mostly I use a Yaesu FT-8900 FM transceiver for operating on the 2-Meter and 70-cm ham bands. A while back, I started getting reports that I had alternator whine on my transmit audio. I was perplexed because I thought I had done a pretty darn good job of installing the radio, including connecting heavy 12V power cables directly to the battery. (See K0BG’s web page for more information on battery connections.) I really wasn’t sure if this was a day one problem (and no one ever told me about the crummy audio) or something that had just started. My first course of action was to ignore it and see if it goes away. This strategy failed miserably as my FCC-licensed spouse continued to report that I was “whining”. Finally, I decided to put my alleged knowledge of electricity to work. I got out my trusty oscilloscope and took a look at the voltage near the transceiver. There was about 800 mV of ripple on the DC voltage, as shown below.

Escape alternator noise 12V at radio - higher revs

The frequency of the ripple was in the audio range, consistent with alternator whine. The frequency of the ripple increased when I rev’d the car engine, so it was clearly coming from the alternator. I was surprised to find that the size of the ripple did not depend much on whether I was transmitting or not. The transmit current is much higher than the receive current, so I expected the ripple to be worse on transmit.

Then I decided to measure the ripple voltage right at the battery, which is shown below. The peak-to-peak ripple is smaller (about 400 mV) than at the radio but still present. I expected the the voltage to be mostly clean right at the battery.

Escape alternator noise 12V at radio - at battery

I pondered what to do next. One approach would be to install a filter to eliminate the ripple. However, filtering out a few hundred Hz signal while maintaining a low voltage drop on the 12V power feed is not trivial. More importantly, I had the sense that the Escape’s electrical system was just not operating properly. I decided to take it to my local mechanic, who tested the alternator and determined that a diode had failed. He replaced the alternator for me and the whine is now gone.

I did measure the 12 volt supply with the new alternator installed and the radio transmitting. I was surprised to find that there is still some ripple, a bit less than 200 mV (shown below). Apparently, this is not enough to disturb the FT-8900 signal.

Escape alternator noise 12V - new alternator 2

So that’s the story about my alternator whine.

My spouse says “I still whine sometimes” but it has nothing to do with my ham transceiver.

    – 73, Bob K0NR

This Interference Seems to Follow Me Everywhere

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USB chargerA few weeks ago, I was at my day job working diligently on something. I popped up the SotaWatch web site to see of anyone was out activating SOTA summits. Sure enough, Steve (AKA Goathiker, AKA WG0AT) was headed up Mt Herman for the day. (I have recently declared Mt Herman to be the Most Radioactive Summit in Colorado…at least for amateur radio.)

When I had a few minutes break, I went out to my amateur-radio equipped SUV in the parking lot to call Steve on 146.52 MHz. Steve came back to my call and we made a quick contact and he was in the log. Even though he was an easy line-of-sight path away, I had trouble copying him. Opening the squelch revealed that I had a large noisy signal sitting on 146.52 MHz. I didn’t think too much of it and assumed it was coming from the vast array of electronic equipment inside the building.

As I left work that day, I tuned to 146.52 MHz to see how quickly the interference disappeared as I drove away. I was surprised to find that the interference did not go away, it was covering a wide area. On my commute home, the noise was remarkably constant. This interference seems to follow me everywhere! Eventually, it sunk in that the interference was coming from my own vehicle. Huh, I didn’t have that problem before.

When I arrived home, I turned off the ignition and the noise was still there. I started disconnecting everything in sight, trying to make the noise disappear. Finally, I unplugged the cute little USB charger/adapter that was inserted into the cigarette lighter socket. Bingo, the interference disappeared. It seems that this little adapter has a switching circuit in it that is generating a large amount of hash. I have not investigated it fully, but it trashes out a substantial portion of the 2 Meter ham band.

It used to be my favorite adapter. Buyer beware.

73, Bob K0NR

Standard USB: Missed It By That Much

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usb-cable-mini-bI’ve blogged in the past about the need for standardization, especially when it comes to computer cables and power adapters. I have been feeling quite good about the progress I have been making with my personal collection of electronic gizmos. I’ve noticed that most of them have lined up behind the idea of using a mini-USB (Universal Serial Bus) port for both power and data. Now how cool is that? Someday, I might be able to carry one USB cable and a AC adapter and have it handle all of my information-age cabling needs.

Then I got a surprise: I upgraded my personal mobile phone to an LG enV3. Great, it also has a little USB connector on it, so it will be compatible with my other devices. Bzzzt. Wrong!  It turns out that the enV 3 has a micro USB port which is about the same width but thinner than the mini USB. It seems that the USB Implementers Forum decided that the mini USB was just a bit too fat for slimmed down mobile phones and personal digital widgets. And the mobile phone industry has decided to standardize on this new slimmer connector.

Then I had to admit that I remember when the mobile phone guys announced this new standard. I just missed the fine point about mini vs micro. I thought we were already mini and micro enough!

I see now that the ham radio manufacturers cleverly avoided this whole mess, clinging to that industry giant, the old reliable RS-232 serial port! Their late adopter (never adopter?) behavior has saved them the agony of flipping the USB port.

On a similar note, Apple will apparently never move away from their proprietary iPod connector, so they have also shielded us from the pain and agony of using an affordable, standard connector.

I guess I need to go find a micro-USB to mini-USB adapter somewhere.  Like this one.

73, Bob K0NR

BPL Coming to Colorado

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Hide the children! Broadband Over Powerline (BPL) is coming to Colorado. Xcel Energy has announced plans to make Boulder the first SmartGridCityTM in the nation. See my previous posting on BPL. The pitch from Xcel is:

The next-generation electricity grid will allow our company to better meet growing demands, address environmental challenges, maximize available resources and optimize the entire energy system. Ultimately, a “smarter” grid helps us serve our customers by creating more options for managing personal energy use, habits and cost.

BPL has caused quite a bit of concern in the amateur radio community due to its use of HF spectrum for data communications via powerline. Some BPL deployments have resulted in considerable interference to licensed amateur radio operators.

Xcel has posted quite a bit of information on their Smart Grid approach on their website. In particular, take a look at the white paper on Smart Grid technology. The good news for ham radio operators is that Xcel is using BPL technology from the Current Group. This implementation of BPL is considered “ham friendly” since there have been multiple deployments of this flavor of BPL that have resulted in no radio interference complaints from the ham community. This could be just luck, but there are technical reasons that indicate Current may have a system that doesn’t interfere with most ham frequencies. The key attributes of the Current BPL system are that the Medium Voltage Lines use 30 to 50 MHz (outside the ham bands) and the Low Voltage Lines use 4 to 21 MHz notched for the ham bands using the Homeplug standard.

The Boulder Amateur Radio Club (BARC) is forming a BPL Committee to monitor the situation locally. We also have an amateur radio BPL team for the state of Colorado.

Note that Xcel is not planning to offer broadband internet service to consumers. At least, not yet. The public relations campaign from Xcel is all about Smart Grid, managing the power grid for maximum efficiency. The BPL industry has been on the Smart Grid path when it became clear that delivering broadband to consumers was going to be economically difficult. I still expect that BPL will die out over time, but it may find a niche market in Smart Grid. Maybe. Keep in mind that wireless technologies can be applied to Smart Grid applications just as well (and maybe more economically) than BPL.

The important thing is to ensure that these BPL deployments don’t mess up the HF spectrum.

73, Bob K0NR

More News on BPL

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The Dallas Morning News reported that Broadband Over Power Lines Plan is Dead in Dallas because Current Communications is bailing out of its plan to offer internet service via BPL. However, Oncor is going to buy the equipment from Current and use it to help manage the power grid. This is consistent with recent trends in the BPL industry that are emphasizing using BPL as part of a “smart grid” strategy and deemphasizing operating as an Internet Service Provider.

An ARRL news article points out BPL is not going away in Dallas but (more importantly) the BPL technology from Current is believed to be “ham friendly.” The reason for this is that Current uses the Homeplug standard on the power lines that go into a residence, which notches out the HF amateur bands, not including 60 Meters. (By the way, the ARRL lab….which basically means Ed Hare W1RFI….got involved with the Homeplug standard early and influenced them to implement this notching.) Where Current equipment is in use, there have been no amateur radio interference complaints.

An article at itbusinessedge.com poses the question “Is it Lights Out for BPL?” Very likely.

In the mean time, the FCC got its hand slapped by the U.S. Court of Appeals for their mishandling of the BPL rulemaking process.

Closer to home in Colorado, Xcel Energy made this announcement:

Xcel Energy announces intended site of Smart Grid City: Boulder, Colo. to become first fully integrated “smart” city in the nation

The current electric grid has served us well for the last half century. But the future requires a technology revolution.

The next-generation electricity grid will allow our company to better meet growing demands, address environmental challenges, maximize available resources and optimize the entire energy system. Ultimately, a “smarter” grid helps us serve our customers by creating more options for managing personal energy use, habits and costs.

Their list of partners in the Smart Grid Consortium includes Current Group, which seems to imply that BPL may be part of the system deployment. It is not clear from their press release that Xcel will be offering internet service to the general public. However, I have heard from a reliable source that Xcel has been telling customers in Boulder that broadband internet service is part of their plan.

You can see the appeal of a Smart Grid approach with all of the focus on “being green.” Managing the power grid and energy demand is one way to get the most out of an electric utility. If a utility can gain some extra revenue by selling broadband internet, that’s even better.

The good news is that the Current Group technology seems to be OK from a ham radio point of view. Other users of the HF spectrum may see things differently.

73, Bob K0NR

ARRL Prevails Against FCC in Court

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Just when the Broadband Over Powerline (BPL) drama was getting extremely boring, the U.S. Court of Appeals in DC ruled in favor of the ARRL, which filed suit against the FCC. Back in May 2007, the ARRL filed an appeal concerning the FCC’s sloppy rule making in determining BPL regulations. Today the court ruled that the FCC failed to comply with the Administrative Procedure Act because they did not disclose all of the documents that they used to make their decisions. It seems that the court concluded that the FCC needed to disclose all of the data available, not just the parts that served their agenda. Also, the court concluded that the FCC did not adequately explain why they chose a 40-dB extrapolation factor (when there was evidence that 20 dB is the right factor).

Read the ARRL story here and the court decision here. This is a signficant loss for the FCC and they have some explaining to do.

Of course, none of this matters since BPL is dying a slow death anyway.

73, Bob K0NR

BPL Provider Ambient Gets FCC Hand Slap

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I guess things must be a bit slow at the FCC Enforcement Bureau this month. They finally got around to responding to the complaints about Ambient’s Briarcliff Manor, NY BPL (Broadband Over Powerline) system. It seems that the FCC has concluded that Ambient has “violated the radiated emission limits of Section 15.109 of the Commission’s Rules”.

You can view the complete FCC letter at http://www.arrl.org/tis/info/HTML/plc/AmbientBPLAdmonishment.pdf

Let’s see…the ARRL first filed a complaint via a letter to the FCC on March 29, 2006. Various hams had filed complaints long before this date. I suppose that the FCC has been rather busy and hasn’t had time to actually do its job of enforcing its own regulations.

OK, so Ambient is clearly violating FCC rules. What’s next?

73, Bob K0NR

FCC Reports on Broadband

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From the ARRL web page:

FCC Releases Broadband Report (Nov 5, 2007) — The FCC has released their latest report summarizing the state of broadband in the US as of December 2006. It shows that in December 2006, Internet-access BPL has increased slightly over December 2005, but also shows that it has been decreasing slightly from a peak that occurred sometime around mid-2006. According to the report, BPL ended up with a deployment total of 0.006 percent of the total broadband lines in the US, compared to 0.011 percent at the end of December 2005.

OK, let’s just see how BPL is doing in terms of adoption. Here are the number of BPL subscribers listed in the report:

June 2005: 4872
December 2005: 4571
June 2006: 5208
December 2006: 4776

So in the last six months of the study, BPL actually declined in use while the other broadband technologies increased by 17 million. See Slow Death for Broadband Over Powerline.

73, Bob K0NR

Slow Death for Broadband Over Power Line (BPL)

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The ham radio community has been rightly concerned about the radio frequency interference potential from most Broadband Over Power Line (BPL) systems. The ARRL continues to do battle with the BPL providers and the FCC over specific RFI issues. Most recently, the ARRL faced the FCC in the US Court of Appeals, challenging the FCC’s regulatory action concerning BPL. The ARRL BPL page shows highlights of BPL activity over the last year.

At the same time, the ARRL Lab Manager Ed Hare, W1RFI, has been working the technical issues with the BPL industry, public utilities, the IEEE and other interested parties. A few BPL equipment companies have taken the amateur radio interference issue seriously and have notched out the ham bands from their devices. Specifically, HomePlug technology and systems based on it (such as BPL systems from Current Technologies ) appear to avoid interference to amateur radio equipment. Other users of the HF spectrum, including shortware broadcast stations, may be hosed since it is only the ham bands that are notched out. While these systems have taken steps to address inteference to amateur radio receivers, interference from amateur radio transmitters is still a big risk.

However, none of this really matters.

The economics of the situation will drive BPL out of the picture, or at least keep the technology limited to certain niche applications. BPL has to overcome the same cost-per-subscriber issue that cable modems and DSL providers face. The myth that BPL will someone light up rural areas with highspeed internet is just that: a myth. The economics don’t support it. The number of repeaters and infrastructure required on the power lines to cover a rural area is just too expensive. This forces BPL to be deployed in areas that are more densely populated….usually areas already served by cable and DSL. Because of this reality, the BPL equipment companies are rapidly moving away from the “broadband for everyone” message and instead are focusing on helping the utilities manage the electrical grid. This “smart grid” story sounds green and plays well into today’s concerns about efficient use of energy, but it does not support the broadband internet vision of the FCC. See the letter to shareholders from the Ambient CEO for more insight into the financial stability of BPL.

Duke Energy was a big proponent of BPL, working with Ambient Corp on a major BPL program. Recently, Duke has decided to “move away from BPL” in favor of wireless technologies, dealing another blow to the BPL industry. In the long run, wireless technologies are the biggest competition for BPL, as they have the potential of covering areas not served by cable and DSL in a cost-effective manner.

Where does this leave the amateur radio community? We will continue to experience RFI at certain isolated locations as various utilities keep trying to make BPL work. There will continue to be battles with the FCC and the utilities over specific interference problems. Systems that are “ham friendly” will fare better than the others. But mostly, BPL will continue its slow journey to the scrap heap of technologies that don’t work economically.

73, Bob K0NR

ARRL Files Appeal of FCC BPL Rules in Federal Court

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The ARRL has taken the next step on challenging the FCC’s sloppy rule making concerning Broadband over Power Line (BPL):

NEWINGTON, CT, May 24, 2007 — The ARRL has filed a federal appeals court brief outlining its case and requesting oral arguments in its petition for review of the FCC’s broadband over power line (BPL) rules. The League has petitioned the US Court of Appeals for the DC Circuit to review the FCC’s October 2004 Report and Order (R&O) in ET Docket 04-37 and its 2006 Memorandum Opinion and Order. In its brief filed May 17, the ARRL contends, among other things, that the FCC’s actions in adopting rules to govern unlicensed BPL systems fundamentally alter the longstanding rights of radio spectrum licensees, including Amateur Radio operators.

The FCC and the Jamming of Cellphones

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CellAntenna, a manufacturer of cellular radio communications solutions, has filed suit in U.S. District Court to force the FCC to allow broader sale of RF jamming equipment (CNET News.com article here). At first look, the argument is compelling: terrorist bombs can be detonated by remote control using cell phones, so let’s jam the phones. Currently, the FBI has access to cellphone jammers that can be deployed but state and local law enforcement is prevented from using these devices. (CellAntenna markets these jammers, so they have a vested interest in expanding their market.) Shouldn’t all law enforcement organizations be able to turn on bomb-blocking jamming equipment?

But here is the context: The Communications Act of 1934 (amended as recently as 1996) provides federal oversight of the radio spectrum. Congress correctly concluded that the radio frequency spectrum needed regulation for the public good. That is, having people transmit on any old frequency any old time they wanted would result in general chaos in the RF world. CellAntenna is asking that the FCC’s authority to regulate the spectrum be overturned. This is a really, really bad idea.

Should the FCC allow local police to jam cellphones? Maybe. But there are plenty of other frequencies that terrorists could use to detonate bombs. Do the police get to jam all of those frequencies, too? Heck, a terrorist could set up an RF control link on one of the local police frequencies. Do they get to jam your WiFi network, your cordless phone, the frequencies of other police and fire departments, etc? This is a real slippery slope, which is why we have a government organization set up to regulate the spectrum and the use of radio transmitters.

But wait there’s more. Some folks would like to use jammers to enforce electronic gadget politeness in public places such as theaters or concert halls. Rude behavior associated with wireless communications devices is generally perceived to be a problem. Most of us have been annoyed by the person that decides to take a cellphone call during a movie or concert. CNET reports that France has authorized the use of jamming devices to enforce cellphone-free zones. Certainly, there are people in the U.S. that would like to see this happen here.

OK, I have to admit, maybe I am just jealous that I don’t get to have a cellphone jammer. This could be really handy for those times when people are practicing rude cellphone behavior, whether on the street or in a theater. Or maybe when I see someone driving down the highway with a phone stuck in their ear and not paying attention to traffic, I could just shut that call down. Hmmm, maybe I could get to like this idea.

73, Bob K0NR