shunt regulator screwup-big time

Wayne100 · 1979

0 Members and 1 Guest are viewing this topic.

Offline Wayne100

  • Newbie
  • *
    • Posts: 6
on: February 07, 2023, 10:32:54 AM
So it has been working for a few months and decided to put in shunt regulator. screwup#1 broke 1 of transistors on c4s board, got a new one and srewup#2 installed it backwards screwup#3 noticed 2 broken wires on c4s board after i turned it on. Got another transistor  rechecked all the wires, had one going to IA should have been to -reg fixed it. Turned it on and b side looked good but a side had no voltage. Turned it off and went back to the amp voltage readings  and terminal 1 and 2 are zero volts term 6 has 31v and term 14 has 1.3v.  Now im lost dont know whether to just take out shunt or did i messup the whole amp?



Offline Paul Birkeland

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 19500
Reply #1 on: February 07, 2023, 12:47:05 PM
If you installed the wire that was supposed to go to IA to -reg, that would short out the high voltage supply to ground and probably blow out the 130 ohm power supply resistors on that side in the process.

You should be able to use your meter to check the DC resistance of those 130 ohm resistors while they are installed in the amp, and I bet at least one of them is open.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man