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March 18, 2024. A Bad Experience ... and not a St Patrick's Day Hangover

As advertised by Amazon 1.6 Watts @ 12VDC good to 512MHz.  Believe what you read from purchaser comments! Too bad I read the comment from WA5BDU after it was in my hands! (With a name like Nick Kennedy (WA5BDU) he might be Irish and a well-known ham homebrewer. He has published a very understandable piece on homebrewing Crystal Filters.) I will not denigrate the above amp by calling it a piece of Crap, but I had terrible experience with trying to make it work. More than 6VDC and it oscillates and the most I got out of it was about 500milliwatts on 20M. The $18 price was like a siren's song that resulted in a shipwreck! With no time to scratch build things I have been making small purchases from Amazon of built boards in hopes of fabricating rigs using purchased modules. So, learn from my sad experience -- avoid purchasing this unit.  If it seems almost too good to be true, 100% of the time it isn't true. 73's Pete N6QW
Recent posts

March 17, 2024. Happy St. Patrick's Day.

St. Patrick, the Patron Saint of Engineers, I was told invented Green Beer. It seems this was his secret weapon to convert the then pagan Irish to Catholicism by getting them drunk on beer. But that may just be Blarney! Were St, Patrick alive today would he be a ham? We do know of one Irish Jesuit Priest who was a well-known ham, 9N1MM , Father Marshall Moran in Nepal, the Voice of the Himalaya's. More tests with the RF Board and indeed the addition of the Band Pass Filter cleaned up the traces. I now get close to 2 VPTP on 40M and less on 20M. I used a BPF (dual 20/40M) built for another rig and noted before that 20M seemed a bit "hinky", so I need to revisit the 20M BPF. 20/40M BPF and SSB Transceiver Board RF Amp Board (Green ~ In Honor of St. Patrick) There are many stories about St. Patrick, and it is interesting to note that four US Presidents have Irish Roots: Biden, Obama, Reagan and Kennedy. (Source CNN.) Even more astonishing all four trace their heritage to the

March 16, 2024. Testing the small find. (Video now working!)

Our small find is tested on transmit.   I finally got a few minutes yesterday to test the RF Amp board on transmit. The results seem pretty positive. The tests were done on both 40M and 20M with more output available on 40M.  The LO versus the RF Amp board likely is responsible. With a 9 MHz Filter the LO on 40M = 16MHz and on 20M the LO = 23MHz. Typically, the output reduces from the Si5351 as you go up in frequency. Small Find Transmit Test. Several posts ago I showed a small RF amplifier board that costs about $7 from Jeff Bezos. Previously I tested it on Receive and yesterday it was time to test it on Transmit.  The output from my test SSB Transceiver was connected on one end to the RF Board and the other end of the RF Board to a 50 Ohm load. The Vcc was 10VDC. Typical output from the test SSB transceiver is 40mv. On 20 Meters we saw about 1.5VPTP (5.625mw, 31.5 dB Gain) and on 40M about 1.8VPTP (8.1mw, 33dB Gain).  These values are consistent with the specs. The max output from t

March 15, 2024. Extreme makeovers.

This is not about a Ty Pennington one week build a new home as seen currently on Netflix.  But this posting is about making over commercial radios where the by-product is an improvement over the original. Inherent in such an undertaking is the ability to look at the commercial radio and spot the possibilities. There are four commercial radios where I have done this and the results were indeed much better than when they came off the Factory Floor. Heathkit HW-101 with a Digital Display and VFO Stabilizer    Ten Tec Triton IV Model 540 converted to a Model 544 (Digital Display)     Keypad Operation of a Ten Tec Model 150A   Hallicrafters FPM-300 Converted to all Solid State   Factory FPM-300 The FPM-300 was the last SSB Transceiver off of the Hallicrafters line. A Hybrid design, it was intended for Fixed, Portable and Mobile Operation (FPM) with a built-in power supply that would operate off of 115AC and 12VDC.  It was a piece of junk! The VFO drifted and it was unreliable. I purchased a