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Author Topic: Another look at the Radio Shack DSP-40 NR / Audio Amp, and maybe improvements.  (Read 484 times)

Offline ThaDood

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http://www.gbppr.net/scanner/dsp40/index.html   I bought one of these at a hamfest, in the late 1990's, for $5.00. I couldn't turn that down, since the components themselves are at least worth that. As with everyone else who has tried one, the results are not that impressive, but my take is that it's great for taking out HET's when someone tunes-up on the FREQ that you want to QSO on. Anyway, after sitting in a bin for like 20-some years, it was time to take yet another look at this unit, and see if there were any modifications to be done with it. Apparently so... I'm going to try these.
“I am often asked how radio works. Well, you see, wire telegraphy
is like a very long cat. You yank his tail in New York and he
meows in Los Angeles. Do you understand this? Now, radio is
exactly the same, except that there is no cat.”
-Attributed to Albert Einstein, but I ripped it from the latest Splatter .PDF March 2025 issue.

Offline Robot Matrix

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I miss the old Radio Shack before they went all CE, cellphones, and later bankrupt. I don't think it was all their fault.  I think people got dumber, and as a result, RS became more irrelevant. I'm currently building an antenna that they used to sell, which you can't find anymore, even on ebay.
eQSL: RobotMatrix@proton.me
NESDR Smart V5, Ham It Up upconverter v1.3, WEB-888 SDR, Inverted L Antenna 20' up and 30' over with adjustable base loading coil, and various other antennas to cover 1kHz-1+GHz. Unless otherwise noted, all signals or broadcasts are received at my QTH with my own gear.

 

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