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I heard a little bit of sporadic-E propagation on 10m this afternoon. Tuning around the beacon segment I heard the beacon DK0TEN on 28.257.5MHz quite strongly for about a minute before it faded away.

There have even been some contacts made and beacons heard on 6 metres, according to VHFDX.info. Let’s hope for some good openings on VHF this year.

I was tuning around the top end of 10m yesterday and noticed a lot of strong bubbly warbly noises, the unmistakable sound of switched mode power supply interference. It didn’t take long to track this down to the power supply for my QNAP TS-109 Turbo Station.

The TS-109 is a network attached storage device. But it is actually a small computer with a big hard drive, running Linux. I use it mainly as a backup drive for all our PCs, but it also hosts the shared documents folder so that we can easily exchange files from one computer to another. It runs a script that updates DynDNS when our IP address changes, which it does quite often at the moment. I could even run a web server on it if I wanted. So it really needs to run all the time. But the amount of interference it produces isn’t acceptable. I tried adding some clamp-on ferrite suppressors but they didn’t make much of a difference.

The power supply for this device is a plug mounted switched mode supply rated at 12V 3A. This is probably over-generous as the specification for the TS-109 gives the power consumption as 14.4W in operation. There are plenty of alternative 12V switched mode supplies available but I have no way of telling whether they would be better or worse than the manufacturer-supplied one as regards RF interference.

The only transformer based power supplies capable of supplying this sort of power are CB radio power supplies such as those sold by Maplin which have a 13.8V DC output. QNAP doesn’t, unfortunately, specify a voltage range for the Turbo Station so I don’t know if this higher voltage would be permissible. It would be very convenient if I could use the power supply I made for my QRP K2, which these days just keeps the K2’s battery charged up, but the output from that is 14.2V.

Switched mode power supplies really are the bane of the radio amateur’s life. I don’t know how to solve this problem at the moment, except to switch off the TS-109, which is inconvenient.

Welcome to Handiham World!

Did you miss us last week?

Image: Pat, WA0TDA, in the ham shack

Your weekly Handiham World E-Letter and the Friday audio notification were on holiday at the very same time that I was on Spring break. What a coincidence that was, eh? I am grateful for our volunteers who still help us to maintain continuity in the Handiham program even when paid staff are out of the office for one reason or another. Volunteers quite simply keep things running behind the scenes as they work with those who need text read into audio format, tapes made and sent out, or a friendly phone call to explain a learning concept or how to operate a radio. Volunteers who give us hands-on help with projects and equipment really make a huge difference in how we are able to serve our Handiham members. When Nancy or I, the Handiham program’s only paid staff, take vacation or have to attend meetings or training related to other aspects of our work, we do still get somewhat behind in our member contact and program administration duties. It can be a little frustrating to have so much work to do and so little time to get it all done. If it weren’t for the volunteers, the Handiham program would never have survived for all of these decades — since 1967. We are so grateful and appreciative for all of the hard work our volunteers do every day.

Thank you, volunteers!

Patrick Tice, Handiham Manager
[email protected]

Camp Courage to go on the air with a new repeater system

Image: ICOM 706 Mark 2G displaying the new repeater frequency of 145.23 MHz

Can you believe it? Handiham Radio Camp begins exactly one month from today, on May 21. As part of our preparations to build a solid amateur radio presence at Camp Courage, our new location near Maple Lake, Minnesota, we are ready to install a 144 MHz repeater that will be on the air 24-7, available not only during the week of camp but all the rest of the year, each and every day. Not only that, but the repeater will be Echolink-enabled. That will provide a valuable resource to any amateur radio operator living or traveling near Camp Courage.

We chose 2 m for several reasons. Many of our Handiham members already have 2 m handheld radios and can bring them to camp. A handheld radio will work perfectly at low power because the repeater will be right at camp and very easy to access. Another very practical reason is that a couple of years ago we received the gift of a used repeater. It needed some repair, and thanks to our volunteer Claire Robinson, K0CJ, we got it in excellent working order. It wasn’t actually put on the air because we didn’t really have a place for it. However, we did get it prepared to go on the air using a pair of 2 m frequencies that is shared and unprotected for purposes of repeater coordination here in Minnesota. Several weeks ago volunteer Don Rice, N0BVE, was helping me with another project at our new headquarters office and I showed him the repeater. Don has taken the initiative to locate the necessary repeater parts such as a duplexer so that we can get the repeater on the air prior to radio camp next month. Dave, N0KP, donated a tone board and tuned the duplexer. There was still the question of an antenna, and Matt Arthur, KA0PQW, has led an effort to procure a new 2 m antenna so that we can do the project right. Several donors have stepped up to the plate to help us with the cost of the antenna, and I will write more about them and the project later on, once we have done the installation. I will also have some photos to share with you.

This new repeater system is not intended to be a wide-area repeater, and the signal will probably not exceed a 20 mile radius from the transmitter. However, reception will be rock-solid at radio camp and the nearby surrounding area. Furthermore, the availability of Echolink on this repeater will make it a fantastic resource that will allow us to stay in touch with Handiham members who cannot make the trip to radio camp but who want to talk with their friends during radio camp week.

In recent years we have had a repeater system and a simplex Echolink node available at radio camp, thanks to Lyle Koehler, K0LR, and Don, N0BVE. These systems operated only during radio camp week and had to be set up and taken down for every camp session. This added to the work that we needed to do during every camp session. The addition of a permanent repeater system will be a welcome improvement to our new headquarters location at Camp Courage.

The new repeater will operate on a frequency of 145.23 MHz with a negative offset and a tone of 114.8 Hz. The antenna will be a Hustler G7 with a gain of seven DB.

One K3 setup adjustment that I have never done is to check the power level of my K3 transverter output, because I don’t have an RF millivoltmeter. I do, however, have an Elecraft DL1 dummy load which has a test point fed by a 1N5711 diode and capacitor. You can take voltage readings there, and then calculate power using the formula:

Power = (( Voltage * 1.414) + 0.15) ^2 / 50

and I normally use this whenever I want an accurate power measurement rather than rely on the readings of analogue meters.

What I don’t know is whether this is accurate enough to measure power at levels as low as 1mW. So I asked the question on the Elecraft email reflector, rashly forgetting that the function of of the reflector is for users to flame each other and speculate on or redesign Elecraft products. Don, W3FPR, who was usually good for an answer to a technical question, has left the reflector after he was flamed for some imagined breach of netiquette. Frankly, the reflector is now worthless. I wish Elecraft would create an announcements-only mailing list so that one could stay informed of new developments and firmware updates without having to see all the ego clashes and endless questions about problems with USB serial adapters.

When I measured, using the DL1 and my DVM, the output from the K3 transverter port with the level set to 1mW, I got a reading of 36mV. Plugging that into the formula, I get 0.8mW. But the 0.15 is, I presume, a “fudge factor” to compensate for the voltage drop in the detector diode, which gives me a result of 0.45mW even if zero voltage was detected. So I’m wondering if my 0.8mW is within the limits of error of my measurement method and that I should leave my transverter drive level as it is. I assembled my K3 myself and the transverter board was added later so I don’t believe the level has ever been set at the factory.

On a clear day from here you can normally see at any one time two or three vapour trails from transatlantic jets at 35,000 feet on their way to London’s airports. For five days there have been none. The weather has been fine and the sky blue, so blue that it’s easy to doubt whether the density of dust from the Eyjafjallajokull volcano in Iceland poses any real threat to aviation, or whether it is just bureaucrats being over-cautious.

Whatever the risk, the aviation ban is real and there can be no-one in Britain who has not been affected by it one way or another. The first effect we noticed was when we went to a classical music concert last Friday in Carlisle. The piano soloist was unable to get there so the Mozart piano concerto was played by a stand-in.

I received an email from one Hong Kong eBay seller to tell me that the programming interface for the Motorola radio I bought at Blackpool which I ordered from him would take longer to arrive. I expect other items I have ordered from eBay and elsewhere, including a transmitter module for my dedicated Echolink node radio, will be similarly delayed, as there is no air mail. We take for granted that we can order things from China or the USA and have them in a few days. Not any longer.

Friends of ours who are due to return from Ukraine tomorrow are probably not going to be able to make it unless London Luton airport is miraculously opened. They are due to return to work on Thursday and are very anxious not to provide their employers with an excuse to terminate their contracts.

That’s the situation now, but with seismologists saying that the volcano could continue to erupt off and on for the next year or two and even suggesting that another, larger Icelandic volcano is due for an eruption, what is the future for the airline industry? If there’s a high probablility of getting stranded abroad like so many people are now, how many are going to decide to change their travel plans and stay close to home for the next few months? I will, for sure.

I dare say canny investors will be selling airline shares and investing in shipping. And I don’t suppose it will be long before the first package holiday companies start going bankrupt because of all the refunds and cancellations. Like the banking collapse, I think this is another event that is going to have permanent repercussions.

Trust Nature to cut us down to size. We humans think we are so powerful we can end global warming, yet in a few hours the earth achieved what governments alone could never have managed – a complete grounding of aviation. I suspect that a really big volcanic eruption could have a bigger impact on global climate than any of the measures agreed by the politicians.

In a comment to an old posting about D-Star in G4VXE’s blog, Lee N2LEE accuses me of being closed to new ideas. Does it matter that the AMBE codec is patented if it is the best one for the job, he asks? And how can you compare Echolink/IRLP to D-Star when D-Star is an digital end to end system with routing, linking and networking built in to the system so you can just enter someone’s callsign and the network will find them automatically?

To me, ham radio is not and never has been about reliable point to point communication. Communication is just the end-product of a process of experimentation and construction, or a pastime (think contests, DXing) where the unreliability and unpredictability of it is what makes it a challenge.

D-Star’s use of a proprietary codec closes that aspect of the system to experimentation. It doesn’t even permit interested amateurs to look at the code and see how it works. This is contrary to the spirit of amateur radio and the openness that has facilitated most developments to date by letting one idea lead to another. But to be honest I’m not all that bothered about the issue because codec technology, whether proprietary or not, is a closed book to most. I am more concerned about the possibility that digital voice modes might one day make analogue modes obsolete so that building a simple phone transmitter using SSB, FM or AM becomes a pointless activity. Ham radio does not have to slavishly adopt new technology, especially if that technology forces more of us to become appliance operators by making simple rigs that anyone can build obsolete.

As for digital end to end routing, why do we need it? We already have a system that can do that. It is called the mobile phone network. I didn’t get into ham radio in order to be able to do something ordinary people can already do. I want to be able to do things that they can’t. The unpredictability of propagation and the uncertainty of who you might work on a given band at any time are what makes a ham radio contact more interesting and more of an accomplishment than making a phone call. D-Star may be very clever technology but what it delivers is not what ham radio is about.

If the time ever comes when I think to myself “why am I struggling to make this contact on 20m SSB or whatever when I could simply type the guy’s call into my D-Star radio and have a comfortable chat” then that is the day I will give up the hobby for good. And I make no excuses for resisting the adoption of technologies that will bring that day closer.