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JCM2-61-00 (2001) iss5.pdfJCM2-62-02 (2001) iss3.pdf
The circuit works for a few seconds until the fuses blow. The components I have checked are on drawings 61-00 and 62-02 in the C5 and C4 area respectively. The fuses are in the D5 area of the 62-02.
On drawing 61-00, the transistors TR1, 2, and 3 check good with a diode check, as does D4. It looks like D3 is a capacitor in the drawing but there is no part there on the board.
On drawing 62-02, D1 and D2 check good. I pulled C15 and C29 and they check good with a cap checker. I also re-flowed the solder on all the jacks on the output board. there were small cracks in the solder on the footswitch jack. I did that before I blew the first set of fuses, which as I said, lasted a few seconds.
It looks to me like the front panel switch SW2 for clean or dirty shorts the +24v supply for the red LED circuit after the 1K resistor R45. That would put 24VDC across 1K for a 240ma. draw. Kind of like killing a fly with a baseball bat.
The + / - 15 volt supply looks good. I connected a 9 volt battery with the correct respective polarity to the anode of D5 and the cathode of D3 and got the same voltage out of each side. I'll be pulling those caps anyway, but at this point I'm a bit frustrated because I can't see anything wrong, and I'm wondering if anybody else has had this particular issue or would like to chime in with an idea. I've checked previous posts on this forum.
Very appreciative of your time.
For reference here are the rest of the drawings.
JCM2-60-02 (2001) iss7.pdfJCM2-63-02 (2001) iss6.pdf
The circuit works for a few seconds until the fuses blow. The components I have checked are on drawings 61-00 and 62-02 in the C5 and C4 area respectively. The fuses are in the D5 area of the 62-02.
On drawing 61-00, the transistors TR1, 2, and 3 check good with a diode check, as does D4. It looks like D3 is a capacitor in the drawing but there is no part there on the board.
On drawing 62-02, D1 and D2 check good. I pulled C15 and C29 and they check good with a cap checker. I also re-flowed the solder on all the jacks on the output board. there were small cracks in the solder on the footswitch jack. I did that before I blew the first set of fuses, which as I said, lasted a few seconds.
It looks to me like the front panel switch SW2 for clean or dirty shorts the +24v supply for the red LED circuit after the 1K resistor R45. That would put 24VDC across 1K for a 240ma. draw. Kind of like killing a fly with a baseball bat.
The + / - 15 volt supply looks good. I connected a 9 volt battery with the correct respective polarity to the anode of D5 and the cathode of D3 and got the same voltage out of each side. I'll be pulling those caps anyway, but at this point I'm a bit frustrated because I can't see anything wrong, and I'm wondering if anybody else has had this particular issue or would like to chime in with an idea. I've checked previous posts on this forum.
Very appreciative of your time.
For reference here are the rest of the drawings.
JCM2-60-02 (2001) iss7.pdfJCM2-63-02 (2001) iss6.pdf
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