emilime75 wrote:
As far as I know, it is OK to test resistors while they are on the board, and they do not need to be removed from the circuit. Is that correct?
Measuring the resistors on the board, R03 and R04 both read the same at 1.485 kOhm.
That looks alright. They should measure 1.5 kOhm +-5%.
As long as we're looking for a short you don't need to remove them from the circuit. But always turn off the device and disconnect it from the mains. Also give the caps some time to discharge.
emilime75 wrote:
Checking all the resistors on the board I determined there is one that reads 0 ohms, and that is R01. All others had a value. I am a bit confused as to the specs of R01 as the online charts don't recognize this color sequence.
R01 and R02 should read 1 Ohm. The last band (the white one) gives the temperature coefficient of the resistor (100 ppm/°C in this case). I found this calculator very helpful:
http://www.okaphone.nl/calc/resistor.shtml?ohm=1&tol=5&tmp=100.
emilime75 wrote:
When checking ICs like the ones on this power supply, do they have to be removed from the circuit or is it OK to measure them on the board?
When looking at what I assume is the front of the IC(the face with the type on it), is pin 1 on the left, pin2 center and pin3 on the right?
If measuring on the board is OK, and assuming I have my pinout correct, IC01 measures 1.490v with the positive probe on pin 1, negative on pin 2. Switching polarity yields a reading of .598v. IC02 yields almost identical readings.
Again as for the resistors, even without removing the parts from the board we should be able to measure a short, so that's fine. You got the pins correct. Can you please check again with the continuity or resistance mode of your DMM. Just to be sure.
emilime75 wrote:
Now, when you mentioned the fuse, something occured to me. I realized I made a big "rookie" mistake here. I was using slow blow fuses, but I made a mistake as to it's rating. The original fuse was difficult to read, but it looked like it said 1.0A 250v. I quickly glanced at the back of the amp case and thought to have confirmed this rating, but just now double checking I see it was actually supposed to be a 10A fuse.
I went down to the local Shack which is the only place near me that carries anything resembling electronic components, and the closest I could get was a 6.3A slow blow, 250v. Should I try turning on the amp with that fuse? Or is more troubleshooting required before I power it on?
Well, looks like Murphy's law got you there. Before you reassemble the amp please take some pictures of the top and bottom side of the power supply PCB. Then we can blend them together later if more troubleshooting is necessary.
10 A is quite a lot, so I'm not sure if I would give it a try. But maybe Tom has an opinion on that, as he's more proficient in devices of this power rating.