No resistance at OB and B3 (Speedballed Crack) [resolved]

Colonl_Charisma · 381

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Offline Colonl_Charisma

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Hi everyone! I switched the output caps to Dayton Audio 100uf/250V film caps today, and when I went to do my resistance checks I did not receive a value at OB or B3. However, OA and B6 had a recorded value of 116 M ohms. The other pins on the octal socket had resistance values except for B3. Ground value on the large board was 0 ohms. Also, resistance checks on the small board checked out.

I did do some desoldering with solder wick in order to open the holes of T6, T7, T9, and T10.

Crack with Speedball was working without issue before.
« Last Edit: December 28, 2020, 05:47:34 AM by Paul Birkeland »

Ross


Offline Paul Birkeland

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Reply #1 on: December 27, 2020, 03:31:44 PM
What are your voltages?

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Colonl_Charisma

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Reply #2 on: December 27, 2020, 03:45:12 PM
I'll check those real quick. I was hesitant to turn the amp on because I did not pass the resistance checks. I'll post voltages soon.

Ross


Offline Colonl_Charisma

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Reply #3 on: December 27, 2020, 04:09:35 PM
Here are my voltages:

OA: 108 V
OB: 108 V
G: 0.5 V
B+: 188.6 V

Ross


Offline Paul Birkeland

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Reply #4 on: December 27, 2020, 04:11:40 PM
What resistances didn't you pass?

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Colonl_Charisma

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Reply #5 on: December 27, 2020, 04:16:18 PM
OB and B3 do not show a resistance on my multimeter. My voltages seem normal though.

Ross


Offline Paul Birkeland

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Reply #6 on: December 27, 2020, 04:19:15 PM
What resistances are called for in the Speedball manual?

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Colonl_Charisma

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Reply #7 on: December 27, 2020, 04:43:29 PM
The manual states that the resistances of OA and OB should be very high, in the hundreds of K ohms (or it could be over the limit of my meter). I looked in my multimeter manual, and it does say that it could take several seconds for very high resistance readings. When I wait several seconds I still do not get a reading.

I am trying to figure out what the display for over limit readings are.

Ross


Offline Paul Birkeland

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Reply #8 on: December 27, 2020, 04:50:21 PM
If your meter isn't returning a reading, it could simply be over the limit of your meter. 

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Colonl_Charisma

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Reply #9 on: December 27, 2020, 04:51:50 PM
I'm thinking that might be the case. If my voltages are checking out can I plug in my headphones and listen to music?

Ross


Offline Paul Birkeland

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Reply #10 on: December 27, 2020, 05:00:39 PM
Yes.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Colonl_Charisma

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Reply #11 on: December 27, 2020, 08:04:27 PM
Thanks, PB! All is well. Looks to have been a false alarm with my multimeter not registering a value because it was over the limit. Amp is working fine and sounding great.

Ross