Bottlehead Crack first build, ALL voltages are wrong [resolved]

nico3las2003 · 1843

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Offline nico3las2003

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Hey, so I just finished building my crack and all the resistance readings checked out fine. But I'm getting wrong voltage readings for all of my terminals. For example, for terminal one I'm getting -00.8.

I'm supposed to check for DC voltage right? I have the multimeter on the V with the solid line and 3 dots underneath.

Also: Both tubes heat up and emit light correctly and I see no smoke
« Last Edit: June 14, 2016, 07:14:06 AM by Caucasian Blackplate »



Offline fullheadofnothing

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Reply #1 on: June 13, 2016, 09:07:34 AM
Yes you should be measuring DC.

Are all of your measurements approximately 0V?
Are you using a clip lead to attach the black probe?
Is your black probe connected to the correct terminal?

Can you post pictures of your build?

Joshua Harris

I Write the Manuals That Make The Whole World Sing
Kit Packer Emeritus


Offline nico3las2003

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Reply #2 on: June 13, 2016, 01:14:52 PM
Yes, all my measurements are approx. 0v and I am sure I am measuring in DC. I do not have a clip lead but I am making sure to correctly place my black probe on terminal 12 or the ground wire.

Here is the build, sorry it's messy it's my first time soldering



Offline Doc B.

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Reply #3 on: June 13, 2016, 01:25:53 PM
Switch you meter to read AC volts. If it has voltage ranges set it for the highest one. With the amp unplugged carefully clip lead the black test lead to power transformer terminal 10. Carefully clip lead the red test lead to power transformer terminal 9. Plug the amp in, switch it on and you should see roughly 150 to 165 Volts AC across terminals 9 and 10. That means the high voltage secondary of the power transformer is working. If you get zero or very close there may be a problem with the connections there. 

Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.


Offline nico3las2003

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Reply #4 on: June 13, 2016, 02:11:34 PM
Hey Doc, I do get a 0 reading on those terminals. Let me try to resolder and retest and I'll update. Thanks.



Offline nico3las2003

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Reply #5 on: June 13, 2016, 02:29:34 PM
Hey, so now I get a 1 reading on AC Volt reading after resoldering. What could be wrong?

EDIT: Hey good news, so i don't know what I did but I redid some of my soldering and I'm getting correct voltage readings. I got every reading correct except at terminal 21 where it jumps to 200 then goes back to 1 consistently, then I saw a spark and unpowered the amp immediately. What is the issue?
« Last Edit: June 13, 2016, 04:41:11 PM by nico3las2003 »



Offline fullheadofnothing

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Reply #6 on: June 14, 2016, 07:07:18 AM
Your meter is most likely in a 200V range, and it is sometimes able to resolve a reading at terminal 21, and at other times it goes over limit, which it displays as a 1 on the left side of the display (as opposed to 1V, which would be a 1 at the right side of the display).

The spark was most likely caused by your probe slipping. This is why we suggest using clips to secure your probe. Go to RadioShack and buy some. I will postulate that most of your measuring issues have been caused by an insecure probe connection, rather than a faulty solder joint.

Joshua Harris

I Write the Manuals That Make The Whole World Sing
Kit Packer Emeritus