brainwagon "There is much pleasure in useless knowledge." — Bertrand Russell


Autodyne receiver for WWV

While scanning QRP-L today, I found an interesting link to a project which gave some details about a little WWV receiver that can serve as a frequency standard.   I haven't had the time to work out how it all works, but it looks reasonably straightforward:

Here's the original schematic from Chuck Adams, K7QO:

Picture 1

Nick, WA5BDU has some variations and additional comments which are interesting:

autodynereceiver kennnick.


A pass of SO-50….

I hadn't worked SAUDISAT 1C (aka Saudi Oscar 50, or SO-50) in quite some time. My recollection was that it was a trickier satellite to work than AO-51, and this pass proved that my recollections were correct. I had significant problems with deep fades. Still, I managed to exchange calls with WD9EWK, K0KU, and N7EDK. Here's the recording.

(I was working this with my TH-D7A HT and my Arrow Antenna).

2010-01-03-SO-50-FM, recording of WD9EWK, K0KU and N7EDK


On responding to threats to our amateur spectrum…

I was driving around a bit yesterday (I needed a new hand nibbling tool to punch some holes in a project box, and wanted to get out of the house anyway, so a jaunt over to Harbor Freight seemed like a good way to kill two birds with one stone) so I did what I normally do: I downloaded a couple of amateur radio podcasts, and fired them up on my car stereo.

One of the podcasts I listen to is the Amateur Radio Newsline, and they were running a story entitled RESTRUCTURING: WIRELESS BROADBAND WANTS MORE SPECTRUM FROM ANYONE. The basic gist (go ahead and listen to the podcast if you like more information) is that Rick Boucher (D) is asking that the federal government undertake a complete inventory of radio spectrum for the purpose of determining reallocations to satisfy the growing need for additional wireless data services. In addressing the possible threats to the amateur service:

Its when you get to 200 MHz and above that the hunt will likely be focused and right there lies the relatively silent 222 to 225 MHz allocation. Above that is the 70 centimeter ham radio allocation which is secondary to the Federal Government. If the government were to decide to move completely out of 70 centimeters it could put a lot of weak signal operators and repeaters in a fight to keep the spectrum on which they now reside.

But likely the real losses would be up in the microwave range where hams hold a lot of spectrum that to date is used mainly by experimenters. And a lot of it sits adjacent to bands used by other services that might eventually be pushed by government decree into moving elsewhere or simply told to disband to make way for more wireless broadband services.

For amateur radio as an FCC licensed communications service this means being vigilant about attempts at reallocations that might include any bands that we use. It also means making certain that our ham radio political leaders are aware that every hertz from DC to light will be under scrutiny by both the wireless broadband industry and the government in the coming months and years.

So, here was my thought: that amateur radio use at UHF+ is actually on very thin ice. The reality of amateur radio at UHF and above is that it's an incredibly fringe activity. I just used K5EHX's repeater search engine to find all repeaters which provide coverage to my QTH. There are 85, but only two are not in the 2m or 70cm band. One is on 6m, the other is on 1285 Mhz. While this isn't the whole story with respect to microwave operation, I think it is indicative of the kind of numbers were are talking about. Probably only one percent of ham radio takes place on the bands above 70cm, and that is probably being rather generous.

When we say that our "ham radio political leaders" should remain vigilant against possible spectrum reallocation, I think that we are shifting the responsibility (and in the future, likely the blame) to them, when the responsibility really lies with us. We as radio amateurs are simply not doing enough to justify our use of UHF+ spectrum. When we rely on political action committees to justify our use of this valuable public resource, we should be working hard to provide them with every possible justification that they can use. It isn't Congress who is placing these frequencies in peril: it is our own inactivity which does so. If we lose 1.2GHz, or 220Mhz, or any of our other allocations, it will be because we frankly aren't using them enough. If I thought that these frequencies could be effectively used to give Internet broadband to millions of underserved Americans, I'd have to say "take those frequencies, we will miss them, but we had our chance with them".

What do you all think?

Filed under: Amateur Radio 3 Comments