[GreenKeys] Dovetron adjustment

[telegrapher at q.com]

The tuning knobs were showing the wrong frequency when receiving the glamorous 170 cycle 45 baud signals.  The alignment procedure was ok for setting the MARK channel but didn't say anything about the Space.  What i finally figured out was to set the Mark freq, monitoring it at the center of the freq alignment pot with a freq counter, and setting it for 2755 cycles.  The going to the space side i set it for 2925 cycles.  That gave me a 170 cycle shift and all the indicators on the Dovetron are happy it appears.  At least i am.  Had to write the results down on paper so i could see what the numbers looked like before it made sense.  Otherwise setting the mark 750 cycles above the front dial reading of 2125 put the frequency at 2875, not what the book said,  Trying to set the space freq at 2295 + 750 cycles didn't work either.  Best to do the adjustment with a good 170 cycle shift signal coming in  cause if the front tuning controls are out of adj, who knows what the transmit side is doing?

Anyway its been a good learning experience.  This MPC1000 is as close to factory condition as you'll ever find.

Larry
W0OGH
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