Low Voltage during Voltage Check

[ssandys]

Hi--

This is my first build, so I appreciate your help and patience.

I've put together my Bottlehead Crack, I passed the resistance checks but on the voltage check, I'm getting a reading of 2-4V at all the terminals which should have voltage (1, 2, 4, 5, 7, and 9).

I do get 122V between L and N. I also am still passing the glow test with the tubes.

Any assistance troubleshooting / debugging would be appreciated.

I've attached a picture of my setup.

Thanks in advance.

sean.

 

[Paul Birkeland]

Here are a bunch of thoughts which may or may not resolve your issues.

First off, there are tons and tons of leads here that aren't trimmed back.  Perhaps the worst offenders I see are at B7 and B8.  If those two terminals are allowed to touch each other, that will destroy your power transformer and require an expensive replacement.  Looking at the twisted ends of the 3K resistors passing through 3U, those look like maybe they weren't trimmed at all.  I see a really long cap lead at terminal 14U as well.

Secondly, you aren't applying enough heat to most of your joints for the solder to flow well, and I see many leads that aren't properly attached.  I would suggest reviewing the instructions in the manual that specify what the word "attach" means, then go through and at least bend up your stripped wire ends and component leads so the solder has a place to flow.

Lastly the amount of solder you've used looks insufficient to get the job done. 

https://www.youtube.com/watch?v=EN16Pi7pcfk

As for why you aren't able to measure voltages, is your meter set to read AC volts or DC volts?

 

[ssandys]

Thanks for the video. I'm working through the feedback.

 

[ssandys]

Progress.

I think we are getting closer. The voltage is now running consistently high at terminals 1,5,7, and 9.  I'm still passing the resistance check and now I have the following measurements for the voltage check.

Terminal	Voltage (DC)
1	145.9
2	161.1
3	-
4	161.4
5	145.4
6	-
7	145.5
8	-
9	144.4
10	-

Thanks again for your help!

 

[Paul Birkeland]

There's still not enough heat and not enough solder on those joints. 

Are the tubes glowing?

 

[kgoss]

Power transformer terminal 15 looks like it is not soldered, and maybe terminal 13 too.