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[davidwpack]

No I haven't done anything with the NFB other than confirm I had the right value resistor and presence pot.

[davidwpack]

Ello! All preamp ohm readings check out and are close to identical. I found a strange difference: moving the leads around, I ended up with a lead on B+ and another on G1 and noticed there was 1.1M resitance. I wrote that number down and turn back around and it read 3.4M so I watched the meter and it climbed over 5M and still rising. I tried multiple times on the loud amp and I can not get it to do this. Don't know how significant that is but it's the only difference in ohm readings I've found so far. Weird? Pots seem to check out too BTW.

[davidwpack]

I think I might have found it. I've got the presence knob wired to the wrong side of the resistor...which also makes the speaker jack wired to the wrong side. I'll get that sorted out. Still don't know what the climbing resistance thing is about. That's not normal right?

[shooter]

That's not normal right?

anytime you measure a B+ node/tap to ground you should get a high R, a climbing R is also good.  Your meter is a power source that is charging a cap, as the cap charges the R goes up.  It's my "quick n dirty" PS check,  If the value is <100k and NOT increasing I start poking around

[davidwpack]

Just because you hook up something wrong twice doesn't make it right...or something like that My mother who lives on the adjacent property with 2 acres between us heard me with the windows closed. Thanks for sticking with me Shooter!!!!!!! Kinda good that it happened or I wouldn't have learned to use a scope otherwise. Thanks again!

[shooter]

 

glad it's LOUD
I believe most here stay because they learn, fixin's just a bonus