Need resistor value Tourmaster 4212

[merlot]

Hello Egnater experts. Newbie here. Just scored a sick Tourmaster 4212 that I'm trying to get up and running. Someone did a mod on the amp and replaced the R100 resistor with a different value. If any of you have your amp chassis out of the cabinet, can you tell me the value of the R100 resistor, (or the color of ribbons on the resistor? I can't find a schematic for this thing anywhere. Thanks. Lots of great information here. I wish I had joined when I had my Rebel 20, but it's gone and now I have the Holy Grail Egnater. Can't wait to get it up to par.
Thanks.

 

[Anonymous]

take a pic and show me where r100 is on the board. i cant see to locate in my pics of my amp chassis innards...

 

[bruce egnater]

R100 is the bias resistor in the power amp circuit. Should be 220K. Can't imagine why someone would have changed it?

 

[merlot]

That's what I guessed, but I feel better knowing for sure. Can't find a schematic anywhere. I don't know what the mod was supposed to accomplish, but the effect was the amp sounded super clean in clean1 and clean2, even at high gain and volume. The other two channels were cold and sterile, with terrible sounding distortion. It's like someone wanted to turn the amp into a Fender Twin on steriods or something. I'll post a pic of the mod when I get home, but in essence the last two power tubes had their grid resistors unsoldered from the board on one end and all were tied together with the bias resistotor for that side, which was also unsoldered from the board. All these resistors were connected to what I assume is one of the inverter coupling caps, which also had one end unsoldered from the board. Without a schematic, I can't imagine what the person was trying to accomplish. Everything is back to normal now and the amp sounds like an Egnater should. Great tones!