P2250 in protect.

Need to completely connect the amplifier assembly. No speakers or load. Find TP 305 on the PAA. Measure for any DC voltage at that TP. Connect your black test lead to the metal chassis ( ground ). Probe the TP with your red test lead.. Be very careful not to short out that TP to anything. If you don't have mini-grabbers for your meter. Wrap some tape around the test probes metal tip leaving just the very end exposed. Heatshrink tubing works very good as well.
 
Ok so the amp is completely assembled both sides. TP305 the point you want me to measure ( 1.4 mV ) is on the PAB amp so I assume you mean to measure on that amp. I also measured TP205 on the bad amp PAA and as suspected because it's now in protect mode again with everything connected I get a OL reading on the meter.
 
Ok so the amp is completely assembled both sides. TP305 the point you want me to measure ( 1.4 mV ) is on the PAB amp so I assume you mean to measure on that amp. I also measured TP205 on the bad amp PAA and as suspected because it's now in protect mode again with everything connected I get a OL reading on the meter.
Put your meter in volts DC range . Not mv range.
 
From now on I'm just concerned with the channel thats known bad.
 
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Thats excellent 1 mv .. The DC servo is doing its thing.
 
Sorry I apologize for being a little confused. You had originally asked me to check TP305 and that location is on the good channel PAB. Lol.
 
This was the good channel. The bad channel had a OL reading on TP205.
What voltage range are you using on your multimeter. I'm kinda exspecting to see rail voltage on the bad channels output. Whatever your + or - B voltage is on the output transistors collector is rail voltage.
 
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Just so I understand..... Did you want me to check the voltage on the Center pin of each of the outputs transistors on the bad channel with negative to chassis/positive to Center pin with power on? I apologize for not understanding what must seem like the simplest of instruction. Oh and the meter was set to auto range the last time I believe.

GT.
 
OL indicates over range on the meter. So if you had selected MV DC rather than V DC any thing over 2 volts would register OL.
 
Did you want me to check the voltage on the Center pin of each of the outputs transistors on the bad channel with negative to chassis/positive to Center pin with power on?
Center pin -Collector. Thats correct.
 
The first transistor. Should I check more than one ? This one measures -70.2 Vdc.
 

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