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Linear Mode
SG Frequency Change With Modulation
462ron
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Posts: 779
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Joined: Feb 2013
City: Shenandoah, State, Province, Country: Pennsylvania
#1

12-06-2019, 08:45 AM
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
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Messages In This Thread
SG Frequency Change With Modulation - by 462ron - 12-06-2019, 08:45 AM
RE: SG Frequency Change With Modulation - by W8ZV - 12-06-2019, 01:30 PM



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  1. The PHILCO Phorum
  2. Various and Sundry Categories
  3. Test Equipment