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SG Frequency Change With Modulation
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Hi all, I have the typical service grade Heathkit signal generator from the 50s, it was my dad's. I have done the typical electronics restoration on it years ago. I usually use AVC voltage as my indicator for peaking things during alignment of a radio. I noticed if I peak things without modulation and then turn on the modulation I need to readjust things just a tad to reach maximum response again. It's as if the signal generator's RF frequency changes some with modulation. I have a frequency counter that I use but when I turn on the modulation the counter goes crazy and I can't read the true frequency. Anyone ever notice this happening? I guess one of these new digital generators might be better but they look to be beyond this old brain's comprehension level to understand. I'm still stuck in an analog world!

Ron

Bendix 0626.      RCA T64  Philco 20B
Philco 41-250.    Philco49-500
GE 201.             Philco 39-25
Motorola 61X13. Philco 46-420     Crosley 52TQ
Philco 37-116.    Philco 70
AK 35                Philco 46-350
Philco 620B.       Zenith Transoceanic B-600
Philco 60B.         Majestic 50
Philco 52-944.    AK 84 


Messages In This Thread
SG Frequency Change With Modulation - by 462ron - 12-06-2019, 09:45 AM
RE: SG Frequency Change With Modulation - by W8ZV - 12-06-2019, 02:30 PM



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