My First Phase Linear Restore- New Guy to the Forum

Mike, the red wire on the left backplane, coud we get a closeup of it?? For some reason that doesn't look right, can't tell though without it being clearer...
 
laatsch55 said:


LOVE THE BABB!!!!!

Did you run a straight edge on the standoffs on the backside to check for too long leads?? Do you have continuity between the backplane ground and the collectors or base bus traces??
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Heck Ya!!. Thought you would like that.

I did run the straight edge a couple times and it checked out fine. I will have to check the continuity between ground and collector/base. the reason I am concerned is because I checked the continuity between the screw holding the thermal device in the middle and some of the jumpers across the right backboard
 
laatsch55 said:
Would you take a pic of the top of the left backplane.?
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Can't take a pic cause I am working the night shift tonight. But I can describe. The red wire goes from the unfused B+ to positive on top power cap. Just looks a little funny cause the wire is long and loops
 
Justrealized pics I uploaded are small. Trying to figureout how to upload higher resolution
 
Can't seem to figure out how to upload higher resolution pics. When I upload from the computer to the website it always decreased size to just a few kb.
 
Go to your user control panel under general options and turn enhanced uploading OFF.
 
Looks like you'll need to pull the Zoebel network off the DC protect board. That's incorporated on the WO backplane boards. I don't have a schematic at my disposal but it's the big ass resistors (looks like one of them is R1) and one of the smaller blue caps for each output that need to be removed.
 
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I removed the above resistors/caps and the unit passed the dimbulb test!!!

Reading through the assembly notes for the backplane it discusses only installing Q11 and Q12 to check the basic offset and bias functions. I did this and my bias is around 45mV in each channel but I can't adjust it much. Is this to be expected as I don't have all the drivers installed yet?

Thanks
 
Correct . Bias will come up but not that much. The resistors and caps need to come off the DC protect board. Those part numbers I quoted were for the dc board .
 
mjstriker said:
I removed the above resistors/caps and the unit passed the dimbulb test!!!

Reading through the assembly notes for the backplane it discusses only installing Q11 and Q12 to check the basic offset and bias functions. I did this and my bias is around 45mV in each channel but I can't adjust it much. Is this to be expected as I don't have all the drivers installed yet?

Thanks
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I would check further... The amp is functional with just the predrivers. Just will not support much of an output load.
 
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