Category Archives: VHF

Video blog episode 011

I finally finished off the 6-meter Yagi project and got it on the air. I’ve actually been using it for a while, but needed the ARRL VHF contest to get enough activity on the band to shoot video in a reasonable amount of time showing me making QSOs. I was running 50 watts into the 4-element Yagi and worked sporadic-E clouds to 30 different Maidenhead grids, including two in New Hampshire, which were my first double-hop sporadic-E QSOs. Enjoy!

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Video blog episode 005

Now that I’ve been working on ham radio antennas, I have a couple of projects for the video blog. The first one is a 6-meter 4-element Yagi. It is designed to be semi-portable, and for me this is particularly important because it’s not practical for me to leave up an antenna for any significant length of time. Perhaps impudently, I am posting this introduction and design video before I actually have the antenna on the air! However, I have tested the antenna itself (sans 1:1 balun) with a VNA and it seems to behave more or less as expected.
I spend a lot of time talking about various design parameters and the actual modeling procedure, so this may seem a little dry if you’ve done this before. But, I try to keep my speech pace relatively slow on these videos, so there’s always the 1.25x and 1.5x speed options on YouTube.  Part II will detail the construction process, and Part III will show testing and hopefully actual on-air performance.

Log: FM E-skip, June 20th, preliminary summary

I was blessed with a major E-skip opening on the 20th. In addition to “live” DXing, and some single-channel audio recordings, I did almost 2 hours of SDR recordings with my Airspy. That provides almost 10 MHz of coverage (the edges of the bandpass tend to not be useful), amounting to around 47 channels available in a single recording. During this event, there were multiple distant stations on most clear frequencies cross-fading in and out, so I pretty much had to fully listen to around 47×2 hours of audio. I also wanted to assess how persistent stations were, so I kept listening for additional identifications of stations even after I had them securely logged. Also, I extracted recordings for nearly all of the stations, so that took additional time. The SDR recordings were biased toward the lower frequencies, so I probably missed a lot of high-band stations. Continue reading

Log: FM E-skip, June 17th

Conditions seem to be staying more summer-like and I had a good opening to eastern Iowa and western Illinois this afternoon that lasted for an hour. I can certainly understand why people get addicted to chasing E-skip! It’s pretty exciting flipping (or clicking, in my case) from frequency to frequency trying to catch identifications from the various stations that are flaring up. With an SDR, I can see the stations flaring up, so doing live DXing is sort of like a game of “whack-a-mole”. Continue reading