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Messages - markorock37

#1
Amplifier Discussion / Re: Carvin R1000 DC on ouput
September 23, 2024, 05:00:33 PM
Yes I definitely put a socket in.
#2
Amplifier Discussion / Re: Carvin R1000 DC on ouput
September 20, 2024, 04:06:44 PM
R221 tested good, replaced A200 5532, showing same results.
#3
Amplifier Discussion / Re: Carvin R1000 DC on ouput
September 19, 2024, 09:52:29 AM
I haven't since they are not in sockets. I have some 5532's I can try. Of course I'll check those resistors first.
#5
Amplifier Discussion / Carvin R1000 DC on ouput
September 18, 2024, 03:01:07 PM
Just replaced the outputs and drivers on Channel 2 on a Carvin R1000. It is on the light bulb limiter. I have -0.4V on channel 1 output, and +2.4V on channel 2 ouput. I replaced D207,208, and 214. D214 is showing 2.4V on each side. Not sure where to check next or where this voltage is coming from.
#6
.2V? My cheap meter probably.
#7
Finally had a chance to get back to it.
T4 Pin 1 -37.3v
       2 +33.9v
       3 -37.8v
T5 Pin 1 +0.6v
       2 +36.2v
       3 +28.6v
T6 Pin 1 +33.9v
       2 +34.1v
       3 +33.7v
Amp is still on dim bulb tester
#8
T3 pin 1 goes to C4
T3 pin 3 goes to R7
So that checks out as well. It would sure be handy if Marshall gave us some voltages and a board layout.
#9
D4 cathode goes to pin 2 of T5
R42 goes to pin 3 of T5
That checks out according to the schematic.
#10
Actually looks like both have CBE pinouts
So T3
c -40.1v
b -40.6v
e -40.6v

T5
c 31.4v
b 39.0v
e 0.6v

Is it possible the new ones dont have the same pinout as the originals?
#13
Well shoot. I was assuming the same pinouts as T1 and T2. Here it is corrected.

T3 E -40.6v
   B -40.6v
   C -40.1v

T5 E 0.6v
   B 39.0v
   C 31.4v

T3 pins 1,2,3=C,B,E
T5 pins 1,2,3=E,B,C

#14
T3 E -40.1v
   B -40.6v
   C -40.6v

T5 E 0.6v
   B 39.0v
   C 31.4v

I'll get some pics up when I can, I'm out of town for a couple days. Had time to snag some voltages before i left.
#15
Well, I've replaced T1 and T2 as well as D1. Still reading pretty much the same voltages. At this point, all transistors have been replaced in the amplifier portion. I hate to deem this unit a loss but I am leaning that way as it was quite a mess with the traces from prior techs. Im 99% sure I have all the traces repaired correctly.