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Correct horizontal frequency??
I will be the first to admit that I am not the sharpest tool in the shed when it comes to television theory. So I need an explanation of the following:
I am working on a 15" Westinghouse for a gentleman who has asked me to restore the set electronically for him.
I replaced a defective trimmer cap in the horizontal oscillator ckt and needed to re-adjust the circuit to the correct frequency. So far no problem.
I go to the Sams and it says 5250 is the frequency. I am reading about of 17Khz with my frequency counter, no where near 5250.
So I take a look at the original Westinghouse factory prints and that same waveform is indicated to be 15750 cps (exactly 3 times what Sams says)
Obviously the correct frequency is 15750, So why does sams say 5250??
In addition, Sams says vertical frequencies are 30 and the Westy schematic says 60 cps.
So can someone please enlighten this old fart as to why the numbers are different in the Sams from what I believe are the correct numbers on the original Westy schematic. I am sure there must be some reason the Sams indicates 5250 but when you actualy measure the frequency it is actually 15750.
In any event I have the Westy horizontal frequency adjusted to 15735 and the horizontal hold locks up perfectly. (it seems the set doesn't want to settle at 15750) and I discovered this is because color sets have 286 lines/field. There was no way you could possibly adjust it to 5250.
I would like to understand this so the next time I run into this I will understand what I am looking at on the Sams. If it wasn't of the fact that I had the original Westy print with the actual frequency, I would still be scratching my head in bewilderment.
Thanks for educating this old fart.
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Last edited by ohohyodafarted; 06-28-2020 at 09:53 PM.
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