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Cobra 2000 GTL frequency counter issue

By gum, it worked! The fix from TSB1232 and new caps did the trick. No more 32 MHz.

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Gotta love it when a plan comes together.

73
 
Probing deeper, and all things being equal, the IC506 5032p pins 12 & 13 aren't outputting a signal whereas the working counter does emit some timing signal spikes. I think it's either the IC506 or the chip it feeds, IC503. Checked both in the same mode with the same vco input. I might as well replace the IC506. It now only displays 33.3333 regardless of mode or channel.
 
Got a socket in today, replaced the IC506 and she's counting on all fingers again.
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I think one finger is longer than it should be, reads 500 hertz high and CT501 won't adjust any lower. I see X501 is running about 250 hertz lower than the stated 10.4858 mhz, maybe it's aged, maybe I can nudge it? I will try.
 

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