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Bottlehead Kits => Crack => Topic started by: Colonl_Charisma on December 27, 2020, 03:11:48 PM

Title: No resistance at OB and B3 (Speedballed Crack) [resolved]
Post by: Colonl_Charisma on December 27, 2020, 03:11:48 PM

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.

Title: Re: No resistance at OB and B3 (Speedballed Crack)
Post by: Paul Birkeland on December 27, 2020, 03:31:44 PM

What are your voltages?

Title: Re: No resistance at OB and B3 (Speedballed Crack)
Post by: Colonl_Charisma 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.

Title: Re: No resistance at OB and B3 (Speedballed Crack)
Post by: Colonl_Charisma 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

Title: Re: No resistance at OB and B3 (Speedballed Crack)
Post by: Paul Birkeland on December 27, 2020, 04:11:40 PM

What resistances didn't you pass?

Title: Re: No resistance at OB and B3 (Speedballed Crack)
Post by: Colonl_Charisma on December 27, 2020, 04:16:18 PM

OB and B3 do not show a resistance on my multimeter. My voltages seem normal though.

Title: Re: No resistance at OB and B3 (Speedballed Crack)
Post by: Paul Birkeland on December 27, 2020, 04:19:15 PM

What resistances are called for in the Speedball manual?

Title: Re: No resistance at OB and B3 (Speedballed Crack)
Post by: Colonl_Charisma 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.

Title: Re: No resistance at OB and B3 (Speedballed Crack)
Post by: Paul Birkeland 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. 

Title: Re: No resistance at OB and B3 (Speedballed Crack)
Post by: Colonl_Charisma 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?

Title: Re: No resistance at OB and B3 (Speedballed Crack)
Post by: Paul Birkeland on December 27, 2020, 05:00:39 PM

Yes.

Title: Re: No resistance at OB and B3 (Speedballed Crack)
Post by: Colonl_Charisma 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.