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The innards of that AK 20 Big Box set
#12

Update on the progress here: I measure resistance/continuity across the primaries and the secondaries of the two RF coils between the antenna coil and the detector, my grid leak is good, and my by-pass capacitor is good (replaced both). I built and set up my AES power supply, made a cloth covered cable in correct AK colors. I also put an extra terminal on the power supply that connects to the green ground on the plug for the power supply (no connection to hot and neutral on that terminal of course--my household power sockets all test good for hot, neutral and gorund connections). I set the A battery voltage to 5v. Hooked it all up...and not much.
I discovered that if I placed the antenna on the screw that has the lead to the grid leak resistor on the tuning gang next to the detector, I could get a tunable signal. I touched the antenna to the grids of both RF tubes and got nothing. I was using a 20' antenna inside the house.
I then ran a lead to my outside 100' antenna, and repeated the experiment. I got a very satisfying loud signal that was tunable to different stations from the screw on the tuning gang by the detector, but I got a much quieter signal from the grid on the 2nd RF tube, and an even more quiet signal on the grid of the 1st RF.
Thoughts?

Charlie in San Antonio


Messages In This Thread
RE: The innards of that AK 20 Big Box set - by ccomer1955 - 06-29-2015, 02:11 PM



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