Crack 1.1 - Voltage Check Fail (Help Please)

[sujith.nair]

Hello Folks,

This is my very first build and facing some issues while performing the final voltage check (numbers below). I am assuming that the 0.XX mv readings can be ignored (where the recommended voltage must be 0 v), if that is true then my main concerns are Terminal 1 and Terminal 7. I also have an LED (connected between 9-pin socket and A8 not glowing).

Terminal   Recommended Voltage   Actual Voltage
1           50-100 v                           150.4 v
2           170 v                           165.4 v
3           0 v                                   0.1 mv
4           170 v                           165.4 v
5           50-100 v                           73.4 v
6           0 v                                   0.5 mv
7           90-115 v                           150.5 v
8           0 v                                   0.7 mv
9           90-115 v                           100.5 v
10           0 v                                   0.4 mv

I have attached pictures of my build for reference. Any and all help/feedback is highly appreciated. Thanks.

[Paul Birkeland]

Can you carefully measure the voltage on A8?

If it's about 12V, then the LED is cooked and is open.  This issue is resolved by replacing the LED.

If it's 0V, then check to see that both halves of the 12AU7 are glowing on the inside.  This is usually caused by the solder joints at A4/A5 not being all the way solid. 

Definitely collect the voltage reading at A8 before trying either fix.

[sujith.nair]

Hi Paul,

Does the above mentioned solution also fix the voltage issues on Terminal 1 and 7.? Please let me know.

Thanks.

[Doc B.]

Yes, once the tube is properly conducting those voltages will move to the proer readings.