Thread: Motorola ts4j
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Old 07-20-2017, 08:16 AM
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Quote:
Originally Posted by tom.j.fla View Post
Best tool to find the fault will be a scope, with a isolation transformer to plug the set into. We do not want to do harm to any gear, tv, or tinkerer for that matter. Without the scope you are just making wild guesses as to what the fault is. All the best,Tom.J
Quote:
Originally Posted by jr_tech View Post
Not likely... I would recheck the wiring between the sync clipper and the vertical oscillator tube... it appears that the vertical sync pulses are not reaching the vertical oscillator. Perhaps a side by side comparison to your VT-73 would reveal an error or wrong part.
Of course, a scope would tell you in seconds if the vertical sync pulses are wrong or missing.

jr
Exactly. [starts chanting] Scope!.. Scope!.. Scope!...

One other thing you may be able to do is try injecting V sync from the VT-73 (or a B&K analyst or test pattern gen) into the VT-71. Make sure the hot chassis polarity matches before applying power or bad things could happen.
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