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Old 07-12-2009, 12:11 AM
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dobulee dobulee is offline
Electrical Engineer
 
Join Date: Dec 2008
Location: Lancaster, PA
Posts: 52
For what it's worth, I came up w/ a way to align the horizontal oscillator frequency without yet having any NTSC sync pulses from the detector stage to use:

I used my computer soundcard to output a 15734Hz sine wave (went for the color standard, not sure why), and used this to trigger my scope. Then I brought in the horizontal on the 2nd channel, and turned the slug until it synchronized. After that, I adjusted the sine wave slug for equal peaks as shown in Sams. However, I ran out of adjustment just before the peaks equalized. At least it's stable now.

Have a little bit of faith in me, here, Bill!

The blanket statement immediately lets you know what I have and have not checked. I haven't gotten to everything yet.

Plate, Cathode, screen and grid of audio amp and audio output - Yes. Checked. These all shared tie points with new film caps and were measured.

The same is not true of resistors in the tuner and IF sections, because I haven't had anything out of circuit there yet. All in due time, but thanks for pointing me to keep looking there.
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