Fender Princeton

[The Dude]

Got it. I suspected this might be the case. So, it's a 'Princeton Reverb' and not a 'Princeton' as the thread title says. FYI, completely different amps.

[bsco]

Got it. I suspected this might be the case. So, it's a 'Princeton Reverb' and not a 'Princeton' as the thread title says. FYI, completely different amps.

I am after finding that out...never realized that at the first of it...
Cheers

[bsco]

ok. back again...I cleaned up tube sockets, re-tensioned tube pins......installed all tubes except the output tubes...bought it up on a variac/isolation xmfr and checked voltages.....all seems to be good....bias measures -28V.........the grid pins of the output tube sockets show no leakage at all.......so now I will install the output tubes and recheck everything.....I will post back later.......

[bsco]

I forgot to mention..I picked up a Sencore AC Powerite PR57 fully functional with leakage probe for $100 CAD.......

[Leo_Gnardo]

..bias measures -28V..

Seems a bit low. Earlier you mentioned bias was -40V. FWIW, depending on what the output tubes are doing I often find Princeton bias somewhere in the -32 to -38 range. Bias current @ 18-22 mA usually enough. I've seen power levels vary anywhere from 10W to 20 at clip, from 200 Hz on up.

[bsco]

Seems a bit low. Earlier you mentioned bias was -40V. FWIW, depending on what the output tubes are doing I often find Princeton bias somewhere in the -32 to -38 range. Bias current @ 18-22 mA usually enough. I've seen power levels vary anywhere from 10W to 20 at clip, from 200 Hz on up.

that was something I found on line before I got the schematic...it looks like -30V on the schematic....and once I installed the output tubes and checked it read -28....I will fire it up later today and test it out.....if it sounds good I will leave it as the owner says it sounds great...just wanted it checked out.....I will post back later as my arm is bothering me again today....I forgot to add this Leo.... I had the amp on the variac set for 117V out....the line voltahe here is over 125...I will have to recheck....I just thought of it....