finished stereomour II amp
- Thread starter Smoses01
- Start date
I have previously successfully built a crack amp and a sex 3.0 kit. Unfortunately, with the past few years in my early 70s, I have developed some shakiness, which is not very good for successful soldering outcomes. Still, I would like to get my Stereomour II kit up and running. It's possible I may need a new power supply, what with no B+ power coming to either channel. I guess the best thing at this point is to return my unit to Bottlehead for repair.
If the proper voltages are coming out of the power transformer, the power transformer is not the problem.Smoses01 said:
If you use your meter to measure a 9V battery, what voltage appears on your meter?
Your wiring around 41 and 44 looks correct, and a short that would drag that to 0V would burn up the 130 ohm resistors, so I would expect to see about 400V DC there.
Ok, I have re-attached a loose white wire to 42L and now have B+ voltage to one side all the way down to the large tube. All along I never have had B+ voltage to the other side. I did a continuity test on the working side and there was continuity between the red wire on the bottom of the plate choke to the red wire on terminal 1. Not so for the other side. I think I may have strained a wire when pulling them through the hole near the plate choke. What is the cost of a new plate choke?
Thank you.
Thank you.
With the amp off and the power supply discharged, set your meter to DC resistance. Now measure the DC resistance between the blue and black wires on the plate choke you believe is bad. Now compare that to the resistance reading on the blue and black wires on the plate choke you believe is good.
For what it's worth, I cannot ever remember a plate choke being damaged in this manner.
For what it's worth, I cannot ever remember a plate choke being damaged in this manner.
Though that is completely wrong, it would not prevent B+ from appearing on either 4 pin socket.
Can you post the voltages on each 4 pin socket for pins 1-4?
Can you post the voltages on each 4 pin socket for pins 1-4?
I would follow the DC voltage along the 130 ohm resistors as it goes toward the A socket to see where it's dropping out. Do also be aware that a missing or loose black wire along the same path would create the same problem.
One other question- I continue with no LEDs lit on the C4s board. So, would that be connected to no B+ voltage on The A channel or is it a separate issue entirely? Since the C4s board processes the sound signal To the small tubes, you can have B+ voltage ok to the 2A3 tubes, (the output tubes), but no sound signal being processed to the first stage tubes.Smoses01 said:
One other question- I continue with no LEDs lit on the C4s board. So, would that be connected to no B+ voltage on The A channel or is it a separate issue entirely? Since the C4s board processes the sound signal To the small tubes, you can have B+ voltage ok to the 2A3 tubes, (the output tubes), but no sound signal being processed to the first stage tubes.Smoses01 said:
I would focus on getting the DC voltages correct on the 4 pin sockets first before worrying about the C4S board.
