I would look for loose components around 34. In the original photos you posted, 35L doesn't look to be well soldered, and those wires moving around could make a pop.
Resistance Checks [resolved]
- Thread starter thoven0215
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thoven0215
Member
I soldered them again, and now I think the pop has taken out the right side too. 19 and 20 measure at 3 volts. 31 measures at 450. 34 measures at 3 volts. 36, 37, 39, 40 all measure at fractions of a volt. 41 measures at 0. 42 measures at 225. 43 measures at 0. 44 measures at 450. 45 measures at 223. Everything else measures at 0.
Loose and/or damaged 130 ohm resistors and/or loose black wires leaving the 41-45 terminal strip will do this. Did you go through the amp and wrap all the connections and resolder them?
thoven0215
Member
I did, and how can I tell if the resistors are damaged? The resistors are not loose, and I just reflowed the terminals 41-45 again just to make sure nothing is out of order.
You have the correct voltages on 41-45, so I would suggest leaving those alone for now. A damaged resistor will measure OL with the amp off and discharged if you try to use your meter to measure it.thoven0215 said:
thoven0215
Member
I attempted measuring them, and both of the 130 ohm resistors measure at infinity.
You can unsolder one end of each and double check them with one end poking up and not connected to anything. Most meters will measure these in circuit, but some will not.
thoven0215
Member
I disconnected them and measured again, but their value just keeps going up until my multimeter can't measure them anymore.
OK, they are probably blown and need to be replaced.
When you get them replaced, you can tape over the metal tip of your red meter probe so only the metal point sticks out, and that should help avoid potentially shorting a terminal with 400V on it to a terminal with 0V on it next door.
When you get them replaced, you can tape over the metal tip of your red meter probe so only the metal point sticks out, and that should help avoid potentially shorting a terminal with 400V on it to a terminal with 0V on it next door.
thoven0215
Member
Just out of curiostiy, is it possible that it could have also been a power transformer issue? Further, I was using alligator clips to measure, and I thought I made sure to not touch other terminals. Could there be an alternate reason for them shorting when I test the terminal? Also where would you recommend me buy resistors? Nevertheless, thank you very much for your help Mr. Birkeland. I will update once I get the resistors.
No.thoven0215 said:
Loose parts will move around when you probe a terminal, and that can cause sparks if they are not well connected. You can e-mail replacementparts(at)bottlehead(dot)com regarding obtaining some new 130 ohm resistors.thoven0215 said:
thoven0215
Member
I don't see anything off, but do be sure that all the striped capacitor ends land on a terminal strip with black wires connecting to it (with the exception of one of the 220uF/250V caps, which will have its striped lead landing where a white wire connects).
If the amp powers up and the fuse doesn't blow, just check the DC voltage at pin 2 on each of the 4 pin sockets. That tells you what you need to know with a lot less fuss.
If the amp powers up and the fuse doesn't blow, just check the DC voltage at pin 2 on each of the 4 pin sockets. That tells you what you need to know with a lot less fuss.
