Wishing everyone a safe, happy, and prosperous New Year! Once again, thanks for all the great feedback on the December issue (and prior issues) of The Logger's Bark, the newsletter & magazine of W7DK, The Radio Club of Tacoma! You can read about the club at www.W7DK.org and if you're ever in Tacoma, WA on a Saturday, the club holds open house almost every Saturday from 10:00 AM to 2:00 PM and all are welcome. Full details at the link. In this month's January 2025 issue of The Logger's Bark magazine: How to assemble a 10m Beacon Station Y2K revisited - 25 years ago this month First rescue with CQD... but it wasn't Titanic! Cool Old Rig of the Month: Ameco R5 receiver Living Histories Videos: All 12 months of 2024 in review Pilot Wasp - the first commercial receiver aimed at hams (not just BCB & SWL users) See the actual first Morse Code key used to SOS from at sea 1964 Bunny Hunt - 6m AM Style! "The Scrounger" - 1963 Build-it transmitter from 1963 Mystery Gizmo: The Wobulator - explained! The New Hot Thing: Apache Labs ANAN G2 SDR Transceiver And a whole bunch more - photos, tips, tricks, blurbs, puzzles, all about amateur radio and NEVER any ads! Download JANUARY 2025 issue of The Logger's Bark HERE: : http://static.qrz.com/w7dk/January2025-QRZ.pdf IMPORTANT: Be sure to actually download it to read - if you merely use Preview mode, the external links won't work! Also, to open a link, "Right Click" > "Open in New Tab". The software I use unfortunately doesn't support "targeted links"... unless you right click, you will leave the document. Here's a lower res version for slower connections: https://static.qrz.com/w7dk/January2025-QRZ-compressed.pdf Dave W7UUU Editor/Publisher [image below is static - the links won't work - download with the link above]
Happy new year 2025. The new edition is intresting again with much to read. To my surprise the searched myterious part is a wobbulator. For me its just a part for jammers or microwave ovens without any intrest for ham-radio. And to use it for electronic music was new, I never configured an analog synth. A HAM-mer club magazine which is seeking its fellow.
There is some colorful ham radio history for me surrounding the "wobbulator". Conrad - W4EBG SK Conrad Bridges was an active on AMer on the low end of 75 meters from the early 60s to the early 70s. He was quite a character and anyone who hung out on 75 and ran across Con would be sure to remember him. Once he was cited by the F.C.C. for using what he called his "wobbulator" which was nothing more than a small motor running at a slow rpm and turning a capacitor attached to his vfo. It was quite effective at discouraging sidebanders although it was illegal. ---------------------------------------------------------- In the mid '60's I hung out with a young upper midwest roundtable ragchew gang on 3803 kHz LSB (the bottom of the 75m phone band then) and encountered Connie many times. Being a young teen I had a distinctively high tone of voice, to which he would growl aspersions at me like, "The one thing I can't stand is a woman on sideband...." Eventually my voice matured, and one of my absolute favorite AM'ers to QSO with today was a pal of Connie, Don @K4KYV, who recounts the use of it below, "Back in the 60's W4EBG and myself each equipped our stations with a "wobbulator". Mine consisted of a small (approx 5 pf) butterfly capacitor coupled to a 3 or 4 rpm motor, and connected across the VFO coil. Con's used a small metal paddle connected to the shaft of about a 100 rpm motor, that swept by the VFO tube. Mine shifted the frequency over a range of about 1 kHz, enough to make it impossible for the slopbuckets to ride the carrier, but not enough to move the signal out of the passband of a typical AM receiver. We both got citations from the FCC for "simultaneous amplitude and frequency modulation". I responded that the "frequency modulation" was not simultaneous because the AM was voice modulation while the FM appeared as a slow drift about every 15 seconds, and that many AM signals on the air at the time drifted and wobbled more than mine (the Knight T-150, for example), many in step with the voice modulation as the modulator current caused the voltage to the VFO to sag. Ben Waple of the FCC responded that yes, the intent of the rule was to prohibit voice modulated FM of an AM transmitter, usually resulting from too little isolation between the oscillator and the modulated stage (the SBE effect, such as from a modulated oscillator or a stock BC-375 transmitter), but that the FCC was interpreting that the rule was not "so limited", and that they interpreted the rules as not to allow one to deliberately adjust their transmitter to conform to the "worst example" of typical on-the-air signals. But in today's Part 97 that rule has been deleted, along with the prohibition of modulation "beyond 100%". There used to be a specific section that made it illegal to run a modulated oscillator. That one has also been deleted. Those changes were the result of Docket 20777, even though the proposed "subband by bandwidth" proposal similar to the recent ARRL petition was not adopted. But I think the idea of shifting frequency at random intervals in random steps might be more effective against automatic notch filters. Has anyone had any experience with how much time it takes for those things to seek out a nearby carrier and lock onto it? This should be easy to set up with a DDS VFO." HNY to all & 73 ! John, WØPV
This also makes me think of synchronous AM which as we know synthesizes a carrier in the receiver to combat fading. How would it react in this situation? I've played with SAM on a KiwiSDR: tune in WWV @ 10 MHz in regular AM mode, tune off carrier by 500 Hz, enable sync AM: the PLL takes maybe 1-2 seconds to lock on (you can hear the carrier being locked in). If you slowly faded that back and forth, I think the radio would have a lot of trouble! 73 de W1PJE
What is (are) the purpose(s) of the above, who are the slopbuckets, and why were the sidebanders being discouraged? 73s Roxy, W4ZMX
(F) Merci beaucoup Je souhaite à tous une heureuse et joyeuse année avec beaucoup de QSO, de bricolage, et tout ce qui tourne autour de notre passion (UK) Thank you very much I wish everyone a sweet and joyful year with lots of QSOs, DIY, and everything that revolves around our passion Great thoughts to all friendships 73's Pascal - F4LPH
A small correction, the "wobbulator" shown on pages 28 and 29 is not part of any test instrument, but instead the voice-coil FM modulator which created the FM-CW waveform used in the AN/APN-1 first generation (WW2) radio altimeter. This was a pioneering design which worked in the 420-460 MHz range, and this made the AN/APN-1 a popular source of parts for early 70 cm amateur experiments. The whole unit is pictured at the bottom of page 29.
Loved the 10m beacon article. Good job! Thank you for the link. I have to shout out a plug for Vlad AA7DJ - he built mine (black box on left). Add a tuner, +12Vdc, and a timer (for shutting off at night) - and bingo ! Rx record so far (10W & a 33' Untimax DXTREAM) is HA5PP @ 4176 mi, +2 dB
