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May 07, 2024, 06:49:29 PM

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#1
Amplifier Discussion / Re: Hartke A35 Repair problems
Last post by Jesse - Today at 04:01:33 PM
ah!, you are correct, I swapped R97 and R98 while typing.
Q9 has fresh thermal paste and seems to be tight to the heatsink.
#2
Amplifier Discussion / Re: Hartke A35 Repair problems
Last post by g1 - Today at 03:41:12 PM
I think you got those R97 and R98 voltages reversed, but voltage across R41 seems normal, and 0V across R98 would be good.
So there seems to be about 50mA current through Q4, which is too much.
Is it possible Q9 is no longer insulated from the heatsink?
#3
Amplifier Discussion / Re: Hartke A35 Repair problems
Last post by Jesse - Today at 02:27:12 PM
R97 is 100 ohms
When voltage across R98 is 5VDC then R97 is 0VDC and the voltage across R41 is 7.4VDC
#4
Amplifier Discussion / Re: Marshall VS100R transistor...
Last post by g1 - Today at 01:52:46 PM
Quote from: markorock37 on Today at 12:59:57 AMIs it possible the new ones dont have the same pinout as the originals?
Yes it is possible.  Measure resistance from D4 cathode to T5.  One of the T5 pins should read zero ohms to D4 cathode.  Which pin is it, pin 1,2, or 3?
Which T5 pin reads short to R42?
#5
Amplifier Discussion / Re: Hartke A35 Repair problems
Last post by g1 - Today at 01:45:13 PM
Can you verifiy that R97 is still 100 ohms?
Also measure voltage across R98 when you have the 5V across R97.
And also voltage across R41.
#6
Amplifier Discussion / Re: Hartke A35 Repair problems
Last post by Jesse - Today at 11:56:39 AM
Thanks g1 and saturated. When the VARIAC is at about 28-30VAC there is 5VDC across R97, and -1VDC at the output. Current draw is still negligible.
#7
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?
#10
The Newcomer's Forum / Re: saturated's all encompassi...
Last post by saturated - May 05, 2024, 11:10:45 PM
Man Joe is getting some really tempting reverb ads on here...must resist  :'(  :P

Anyhow I found that if you are playing a song off YouTube on your phone like trying to learn it while you play...if you hold it up to your pickups it will play through your amp

:P  :-[  :-[  8)