brainwagon

I previously made a half-assed “cheap yagi” just using some aluminum wire and a scrap of wood from the garage, but I’ve been thinking of making something a bit more permanent. What I needed was some practical information on tools and techniques, and this is so far the best article that I managed to find, […]

Saw this drift by on the KnightsQRSS mailing list, looks very promising. Also makes me think that I should have gotten my own program ready for release. Sigh, I’m a bum. >>> QRSS VD – The Free, Open-Source, Cross-Platform QRSS Spectrograph by AJ4VD « SWHarden.com.

Once again, Roger G3XBM has provided me with links to interesting and inspiring reading. Roger is now interested in experimentation below 9khz. He found this very interesting blog called: VLFradio.com

Overnight I heard and was heard by a number of VK and ZL stations, but perhaps my most interesting spot was from long time QRSS/grabber/WSPR participant W1BW. Despite the fact that he was running a mere 5mw, I managed to pick him up twice overnight: 2 spots: Timestamp Call MHz SNR Drift Grid Pwr Reporter […]

I was reading the pre-announcement for this month’s QST, which apparently includes a product review for a new tri-band Alinco HT: The Alinco DJ-G7T. It is intriguing because it includes two features which are uncommon. First, in addition to 2m and 70cm, it includes operation on 1.2Ghz. But more importantly from my perspective, it is […]

Yesterday I spent some time trying to implement a simulation of an SSB exciter that worked by using the Hilbert transform on some input audio, and then multiplying it through by a carrier signal in quadrature and summing (or differencing) the two resulting streams to produce the LSB or USB. I was getting poor cancellatio […]

I’m gonna dash off to an appointment with my tax guy in a few minutes, so I’ll have to be brief. I’ve been reviewing literature on inexpensive/simple phasing double sideband and single sideband transmitters. It dawned on me that while it was pretty simple to generate the necessary quadrature signals for the carrier frequency (the […]

I was reading amateur radio blogs and for the third time or so in a month, I was treated to what amounted to a diatribe against software defined radio. When I read these, I can’t help but sigh in frustration. I understand nostalgia. We all like the cars we wish we could have had when […]

Well, yesterday I was out shopping at HRO, and couldn’t resist the allure of a new Signalink USB sound interface for my FT-817. This is a sound interface that looks just like a USB sound card when you plug it in, and has rx and tx volume controls on the front. So, of course, I […]

You’ve had a C compiler sitting in front of you and some communications textbooks, and so you’ve done some hard work and created a new digital mode that you’d like to see widely deployed. What should you do? Well, let’s begin with what you should not do: First, you shouldn’t presume to dictate what frequencies […]

This wasn’t quite a personal DX record for me, but it was close, and the first time I’ve heard South Africa in quite some time. I spotted ZS1LS twice this morning on 30m, from grid square JF96fd and a distance of 16477 kilometers. I had previously heard ZS6Y (16927 km) and ZS1TX (16492 km), and […]

While tuning around, I found some of the VOLMET traffic from NY this evening. In trying to identify other aeronautical signals on HF, I discovered this rather nice map, which I thought I’d archive for future reference. I should print this out and get it laminated. HFAERO.jpg (3397×1781).

I was looking for some information on how to compute the resonant frequencies that are attainable from small loop antennas, especially for VLF. This appears to be precisely what I’m looking for. This article describes how to build a loop antenna for low frequency (LF) and medium wave (MW) reception with remote-controlled tuning. The antenna […]

AK6L was installing an attic dipole, and idly wondered what the maximum inductance and capacitance the LDG Z11 Pro could swap in. He sent LDG an email, and got a quick response, and since I have the same tuner, I thought I’d write down what they said for future reference. Apparently, it can use 15uH […]

httpv://www.youtube.com/watch?v=DYktDghfoFM Addendum: It seems rather likely that the person photographing this was the yutz who tossed the branch up there. Don’t try this at home, folks.