WOPL 400 1st time build

George S. said:
If you think a output may have a bent pin or they were just very hard to line up, then check them against one of the original sockets. The pins were very blunt on the last amp I built compared to the two prior amps. Several outputs needed a little tweek, then no issues.
Also as Joe says, photos. Joe spots issues right away.
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after you install a row...check inside that the pins come through the backplanes...that way you know you did not bend a leg...good luch
 
Gene, that's a great idea! Also, only tighten those output bolts until the silpads edge begins to curl or wrinkle, then stop. Yup, tomorrows another day. Later.
 
Good morning. I just wanted to ask if the testing in the bringup instructions is required or if I could just redo the power transistors and check each row with the DBT? Because I don't have the resistors required lying around.
 
plex said:
Good morning. I just wanted to ask if the testing in the bringup instructions is required or if I could just redo the power transistors and check each row with the DBT? Because I don't have the resistors required lying around.
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Peter if you have tested with transistors in the bottom row, you are well beyond any steps that require the resistors you reference except to discharge the bulk caps. You do not want to be doing anything with residual charge of more than ~0.5V in each bulk cap or you will damage things.
 

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Thanks Joe for the help, and for having patience with this newbie. You're spot on George-I'm rushing.
 
Sorry for the large photos. I misplaced my other phone. Will try to take more.
 

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plex said:
Sorry for the large photos. I misplaced my other phone. Will try to take more.
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The green wire from the copper input jack plate to the bus bar ground between the 2 bulk caps is not required or desired, should be removed. You should be able to temporarily disconnect the shield connections to PAD 2L and 2R and confirm that there is NO CONNECTION of this copper plate to the chassis or to the bulk cap bus bar ground. After confirming that, reattach the shield connections to PAD 2L and 2R
 
With my Variac at 120 VAC output, and a 75 watt bulb in the DBT, my bulb showed a deep orange glow, but no where near white light spectrum. Are you seeing white light?
 
Additional info on the RCA copper plate. Green wire gets removed, coax shields get soldered to plate or RCA grounding tab. RCAs are insulated from the chassis with the fiber washers, copper plate makes contact with both RCAs and coax shields. Hence, the copper plate RCA assembly floats above chassis ground.
 
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