finished stereomour II amp

Smoses01 said:
Would resistance between black and blue wires of 620k ohms for both Channels be reasonable figures? I configured my chokes for 8 ohms.

That would be your output transformers, not your chokes.  I would focus on tracing the B+ along the 130 ohm resistors to see where it's dropping out and not be too concerned about the chokes right now.
 
I have checked where voltage drops off: here is an overview of major high voltages I got, as well as areas of concern that are starred: thanks for any assistance that can be given!

Voltage checks:

*1-2: 0 volts dc
14: 170-230
19: 418
20: 418
20: 385
*27: 0 volts
*30: 0 volts
31: 418
34: 418
IB: red wire to printed circuit board: 418v


 
44 and 30 aren't connected properly by the 130 ohm resistor, it's missing, or it has burned up (which would be very visible).

A blown plate choke would give you 400V at terminal 27.
 
Big goof! I accidentally shorted my power supply! (Sparks and loud pop). Now I have no B+ power on the side was working correctly. Interestingly, voltage checks to primary and secondary are normal.  Also, I’m still getting high voltage 400 volts at the rectifier right at the connection
To the power supply. Checked the tubes and they appear to be ok. I think that I will need to replace the power transformer and any other parts that you think may have been damaged with the short. What do you think? Thank you!!
 
Smoses01 said:
I think that I will need to replace the power transformer
Why?

If you read back through this support thread, repeatedly you have asked to purchase replacements of the most expensive and most difficult to replace parts in this kit, and there has never been any data presented on your part that would necessitate having these items replaced.  Even in the event that one of these parts needs to be replaced, we have to sort out here why it failed in the first place so we don't sell you an expensive transformer only to have you install it immediately damage it in the same manner that caused the original part to fail. 

Any parts requests like this that get sent in will get reviewed pretty carefully so we don't end up in this situation and also to be sure we aren't replacing components that haven't actually failed.  We also have written into the manual a set of checks to verify proper operation of the power transformer and performing these tests is the first step (but not the only step!) in determining if there's a power transformer problem.
 
You are absolutely correct. The last thing that. I want to do is replace an expensive part like the power supply unless it is absolutely necessary. When I accidentally short circuited my power supply and saw sparks and heard a pop, I thought it was very bad news. Then, when I checked for B+ power on the side that had been working properly, I saw that there was none combing to the 2A3 tube spot. I will do things a bit more methodically from now on. Thanks, Stephen Moses.
 
Back
Top