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Old 03-27-2009, 07:09 PM
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radiotvnut radiotvnut is offline
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Location: Meridian, MS
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I found the Sams. What are the board location numbers of those two resistors in question?

As far as the shorted HOT blowing something, I'd suspect R007 (5.6 ohm, 2 watt) and/or R001 (1 ohm, 6 watt). One end of R001 connects to one of the contacts on the power relay and the other end connects to the cathode of D002 and the anode of D004. These are two of the four diodes that make up the bridge rectifier in the power supply and the cathode is the end of the diode with the white or silver band.

R007 connects to pin 3 of the regulator.

If these resistors are good, measure the B+ voltage. Take your voltmeter ans set it to measure at least 200 volts DC. Connect the negative lead to one of the heatsinks and the positive lead to pin 4 of the STR regulator IC or pin 2 of the flyback. Turn the set on and you should measure around 130 volts DC. If the voltage is much higher, like in the 160 volt range, either the regulator circuit is not operating properly or the horizontal circuit is not operating. These types of regulators must have a proper load in order to regulate properly.

If the voltage is lower than 130, unsolder pin 2 of the flyback and check again. If the voltage jumps up, the flyback is most likely bad.
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