My WOPL 700 Containment Thread

mr_rye89

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#41
Did the quick test procedure on the right side of the control board. everything checks out there except Q6 and Q9 get pretty warm. maybe the right backplane is suspect?
 

Gepetto

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#42
Did the quick test procedure on the right side of the control board. everything checks out there except Q6 and Q9 get pretty warm. maybe the right backplane is suspect?
It is rare but sometimes coincidences do happen...glad you are vectored onto finding where the problem is...
 

mr_rye89

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#43
Are Q6 and Q9 supposed to get warm during the quick check procedure? I looked over the right back plane and didn't see anything obvious. I'm thinking I made a bad connection somewhere.......
 

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#44
Are Q6 and Q9 supposed to get warm during the quick check procedure? I looked over the right back plane and didn't see anything obvious. I'm thinking I made a bad connection somewhere.......
You have a full comp setup so I am assuming that your quick check procedure is that of having no devices installed on the backplane boards and testing for bias.Q6 and Q9 typically do not get very warm under any circumstance.
 

mr_rye89

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#45
You have a full comp setup so I am assuming that your quick check procedure is that of having no devices installed on the backplane boards and testing for bias.Q6 and Q9 typically do not get very warm under any circumstance.
Ok, I'll check Q6/Q9 when I get home. The voltages across the 47 ohm resistors went between .8 an 1 volts when turning the bias pot.
 

mr_rye89

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#46
Found it. R2 (1 ohm 1/4 watt) not populated on the right channel back plane board. Hiding underneath that emitter resistor. That ties right in to the bias circuit. Soldered that in and I have healthy bias voltage on the right channel. Lol.
 

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Gepetto

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#47
Found it. R2 (1 ohm 1/4 watt) not populated on the right channel back plane board. Hiding underneath that emitter resistor. That ties right in to the bias circuit. Soldered that in and I have healthy bias voltage on the right channel. Lol.
Parts matter Kyle... :)
 
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