SolderSmoke Podcast #235 is available for download:
One contact on uBITX. More SW listening.
Repaired my Chrome Book in Santo Domingo!
Christmas Present for All: James Web Space Telescope launch
Serving the worldwide community of radio-electronic homebrewers. Providing blog support to the SolderSmoke podcast: http://soldersmoke.com
2) Try putting a series LC shunt circuit tuned to 41 MHz at the output of the carrier oscillator (between the oscillator and the buffer).
3) Reduce the voltage to the oscillator/buffer. I have this on a pot, so I can adjust it down to the point where the remnant of the harmonic is no longer audible, while keeping the main carrier osc signal sufficiently strong.
It seemed to work. I could now hear the desired frequency for spotting, without the confusing tone from the spur.
Why had I been able to do this back in 2002 in the Azores using a simple trimmer cap to ground? My guess is that I was using my Drake 2-B as the receiver. The trimmer cap to ground may have reduced harmonic output. And I was probably cranking back the RF gain on the 2-B to the point where I could hear the desired signal but not the remnants of the spur. I have no RF gain control on the Barebones Barbados receiver that I am using in this project.
So, what's the lesson from all this? Well, if you are faced with a serious technical problem, and you find yourself considering complicated and difficult solutions, go to the Dominican Republic for about a month (especially if it is January or February), and then take another look at the problem when you return. If you are unable to travel this far or for this long, taking a walk or taking a weekend break from a troublesome problem will likely have a similar mind-clearing effect.
The video above shows part of a February 1, 2022 QSO with Gar WA5FWC using the split TX/RX 17 meter rig. Gar is an amazing long-time SSB homebrewer who got his start with phasing rigs back in the day.
A view of McMath Region 11976 from the Paris Observatory early on 4 August 1972.
I have a vivid memory of seeing -- as a kid -- Aurora from our home near New York City. Eric Carlsen, my childhood friend and colleague from the Waters Edge Rocket Research Society, told me his mom had similar memories. A while back I did some Googling and concluded that it had to have been the monster solar flare of August 1972:
https://soldersmoke.blogspot.com/2009/09/carrington-flares-aurora-where-were-you.html
That blog post got about eight comments, mostly from other folks with similar memories -- they apparently were led to my blog by the same kind of memory-based Googling that I had done.
This year, on Christmas Eve, Elisa and I were flying home from the Dominican Republic. I was reading (on my phone) "To Hold Up the Sky," an anthology of Cixin Liu's science fiction short-stories. I'd read his excellent "Three body Problem" in the Dominican Republic back in December 2017. His work is usually "hard" sic-fi, with a strong connection to real physics.
One of the short stories in the anthology is entitled "Full Spectrum Barrage Jamming." Wow, I thought, that one is really promises to be very interesting for a radio amateur. I turned out that it was more interesting than I expected.
I won't spoil the story for you. Suffice it to say that Cixin Liu makes reference to the same August 1972 solar flare that I remember from my childhood, and discusses its effect on radio propagation. It was really kind of eerie to be in that plane, flying over the Bahamas, reading Chi-Fi on my I-phone, and seeing the author reference that memorable event from 1972. TRGHS.
There were plans to turn this story into a movie: https://www.yicaiglobal.com/news/wandering-earth-producer-to-film-another-liu-cixin-novel
Here is an excellent article describing what happened back in 1972: https://room.eu.com/article/lessons-from-the-sun. The August 1972 flare was so strong that it caused U.S. Navy anti-ship mines to explode in Haiphong harbor in Vietnam.
The fishing pole worked well, but I operated with fear that it would fall or that the neighbors would complain). Today I got on 17 CW with the uBITX (more power than the SST), put it on 17 CW and promptly worked W4A, a special events station commemorating E. Howard Armstrong. Turns out that today is Armstrong's birthday. TRGHS.
On the Reverse Beacon Network my CQs were heard by KO7SS in Arizona (very cool skimmer station at 8100 feet!) and by W2NAF (interesting operations in Antarctica, Svalbard and Virginia Tech).
DX-390 Main Board. Note kludged toroidal replacment for L10 (just above ferrite antenna) |
Kludged in J310. And two sets of back to back diodes |
Lifted solder pads. And small wires that now bridge the gaps |
ATS 818 marking along the bottom (green) part of the PLL board |
Bill's Bavaro DR Beach Station uBITX in the box, HB key |
Pete's Plank SDR When you know stuff, you can do stuff! |
767 |
The point of the Pen shows where we were in Samana. Bavaro is on the Eastern tip if the island. |