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Issue with rebuilt 38-690 audio transformer
#14

Read my post above.

Start your check with pulling the rectifier and checking the AC outs.
Power down.
Then measure the load across the rectifier output, check if short is present.
If not, put rectifier in, put the loads (speakers) in, power up, briefly see if the DC develops and where it goes, once reached about 500V it should go down a bit and stabilize. Watch for smoke.
Power down AND watch the DC going down. If very slow, you have no load. If fast (second or few) - OK.

Once this is OK, start measuring voltages.
Check the transformers' continuities, check speakers.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.


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RE: Issue with rebuilt 38-690 audio transformer - by morzh - 06-30-2015, 04:28 PM



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