No Power - Help Needed

[jdappel]

I am a new Bottlehead owner and completed the s.e.x. 3.0 kit over Christmas. It was a trip to build and apart from a few mistakes, it fired up and played beautifully from the beginning. Until about a week ago. It shut off during operation and now it won't turn on at all. I tested the fuse and it is good. But turning on the power switch when plugged in nothing happens (the heaters don't turn on, nothing). I'm looking for suggestions as to where to begin troubleshooting. Any help would be appreciated. Thanks!

JDA

 

[Paul Birkeland]

How did you check the fuse?

I would go back into the manual and go to the section where you test the powerline voltage on page 28 and let us know if you are able to see incoming wall voltage.

-PB

 

[jdappel]

I tested the fuse with a volt meter. I’m getting voltage on the power line voltage test.

 

[Paul Birkeland]

If this is a SEX 3.0, you can go back and do the incoming AC voltage checks (which it sounds like you did), power transformer AC voltage check, and DC voltage check.  The results of these tests will likely be enough to pinpoint where your issue is. 

-PB

 

[jdappel]

Ok. I tested the AC and DC voltage as you suggested and here’s what I found. AC looks ok. DC not so much. Here are the DC readings from pg. 61 of the 3.0 manual.

2-46
3-0
4-all over the place
5-0
6-47
7-48
10-486
16-465
17-0
18- all over
19-0
20-473
21-483
24-482

H2-5.2
H5-5.4
H4-0
H7-0

 

[Paul Birkeland]

What is your measured AC line voltage, where do you live, and what did you wire for during the build?

Do both the tubes glow?

 

[jdappel]

It is 122 volts. I live in ID and I wired for the 4ohm build (if that’s what you mean). I also wired using the 115-130 volts section of the manual.

 

[jdappel]

Also, I get no glow from the tubes.

 

[Paul Birkeland]

OK, well you have DC voltage on the "H" terminals that are responsible for making the tubes glow.  This is the wiring that runs to pins 1 and 12 on each tube socket.  There is likely a break in this wiring or a loose connection that's causing that problems.  Once you get those tubes glowing again, the rest of the voltages will change dramatically.