[Heathkit] UPDATE SB-610 phase networks needed

[K3PID]

Just an FYI, re the tone frequency of my SB-610. You may recall that I measured 1900+ for the 1500 Hz tone and 2350 for the 1950 Hz tone. The 2350 bothered me because it is close to the bandwidth for SSB. Some in this list advised that the culprit might be the 220 K resistors in the grid circuit and that they often shift with age. Well although it is about 6 pounds of stuff in a 1 pound sack ( the area around V4 is really crowded ) I took out the two 220 K resistors and they indeed measured about 25% high... Then I discovered that pin 10 of the V4 socket was all but broken off and inserting the tube one more time might be the last straw... so... as they say.. I went in! I took out the 12 pin socket and replaced it, then rewired the mess but with new caps and resistors using 1% 220 K resistors since they are part of the phase shift network. 

VIOLA! The tones now measure 1525 Hz for the 1500 Hz and 1958 Hz for the 1950 Hz. MUCH BETTER!!!

Ron H
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