2002 board blowing fuses with no power tubes in.
I started at the power transformer and was able to get to SP1 choke connection until it started blowing fuses.
So I can disconnect SP1, leave all OT connections intact, and it doesn't blow fuses. Voltages at OT CT is good 480V, and same at plate leads
At that point I noticed the filter cap at the node of the OTHER side of the choke(SP2) had a broken lead, so I replaced it, thinking that would do it.
It still was blowing fuses, so isolate even further, from the other end of B+, I disconnect one end of the 4K7 R74 at the "Z" node, and the amp is blowing.
So it's gotta be the choke, right? I subbed in a 270r 10W, and it started smoking. I further tested the choke by leaving SP1 connected, and removing SP2 . Amp didn't blow.
So I believ the OT and choke to be OK
So that narrows it down to the Z node, right? That's the screen node, and the only thing at the end of that road is the screen Rs . They both read 470r, so short of replacing them, what else could even be a possibility?
Schematic p10 : http://badraven.com/Fender_Manuals/H...d%20Deluxe.pdf
I started at the power transformer and was able to get to SP1 choke connection until it started blowing fuses.
So I can disconnect SP1, leave all OT connections intact, and it doesn't blow fuses. Voltages at OT CT is good 480V, and same at plate leads
At that point I noticed the filter cap at the node of the OTHER side of the choke(SP2) had a broken lead, so I replaced it, thinking that would do it.
It still was blowing fuses, so isolate even further, from the other end of B+, I disconnect one end of the 4K7 R74 at the "Z" node, and the amp is blowing.
So it's gotta be the choke, right? I subbed in a 270r 10W, and it started smoking. I further tested the choke by leaving SP1 connected, and removing SP2 . Amp didn't blow.
So I believ the OT and choke to be OK
So that narrows it down to the Z node, right? That's the screen node, and the only thing at the end of that road is the screen Rs . They both read 470r, so short of replacing them, what else could even be a possibility?
Schematic p10 : http://badraven.com/Fender_Manuals/H...d%20Deluxe.pdf
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