Stephen's WOPL Build

The tape is used to hold the solder cups to the board so you can turn the board over and solder them in. The solder cups are an insert set into the board as a place for the output transistor leads to land. They provide a snug fit for continuity and are rated to 8 amps....
 
Backplanes ready for wire...
 

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Thank you for the great step by step & sssharp pics Lee! I'm making a folder.
I'd really like to see the testing procedure you use . Exactly where you hook your probes for each test. I've been reading a lot of threads & this seems to be a confusing issue for builders.Some folks might be embarrased to ask......I'm not that proud.
 
Brad, when I test this bugger, I'll get more detailed than ever before....
 
Yep very nice work there buddy!! :cheers: I've had the pleasure of meeting Mr. Stephen Evans thanks to Lee.

All I can say is WOW!! :love4:, he is a gentleman par excellence, Amazing gear, amazing ear, story teller like no other, and need I mention he is a Thorens turntable guru, he had his buddy drive to LA to grab my SAE A1001 and used it, loved that I bought the Summits :king: !! I could go on and on!!! Sooo very glad he'll get that amp Lee!!! I gotta call him, lost his #, call me tonight buddy and give it to me!! OooooDaddy :3some: Hehehe!! Sorry, man crush, love ya guys!!!
 
Sheking down the stocker for before measurements. Checking Bias right now, kinda high...452 MV....

Bradrock---Positive lead on the base bus bar, negative lead on the emitter resistor common tie point.....


Another weird point, adjustment range is only 429 mv to 490 mv.....both channels...
 

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Another anomaly , a cap and resistor in series on 2 legs of Q8........
 

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DC offset, left and right channels.....left 6 mv, right 16mv, for a stocker , pretty damn good..

Bradrock---Negative lead on the PS cap bus bar, positive lead on the collector bus wire of the negative drive of each channel ( which is also the output for that channel) If you want to check DC offset without opening up the amp, just measure across the speaker posts....
 

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So you're going to do a pre and post mod test for this beast? If so cool. The newbies should enjoy this.
 
Yeah, been awhile since we did one and have a few new members....
 
Time to test...

Notice no sticker on the transformer?? I've been told that Bob would come in and grab one off the line if he needed one. I guess they didn't get a sticker until after QC.....

This load cell is from the PL factory, even has the PL machinery sticker on it....
 

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Residual noise, left and right channel, UNWEIGHTED......Inputs shorted, mains in 122.1 volts, DC offset, left 6mv, right 17mv, Bias, 429mv left, 432mv right...


 

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I have no idea why the attachments came out so small. When I scanned the documents and saved them they look normal size in the file I saved???

Docs are 627KB in my file folder and only 7kb here....WTF??
 
Good, that's my favorite Cheerios :blob3:
 
Let me try again...still don't know why a 674kb file is getting transferred as a 7kb file...
 

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