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Craig,
I’m sorry to hear about your jumper trouble. First of all, do not use a conductive pen to try to fix this. You need to just bypass the jumper pads with a jumper wire. It appears that you have your iron set to a much lower temperature than you should…i keep my Hakko FX-600 set to 575 F, which is around 300 degrees C. With the temperature set this much higher you’ll probably need to adjust your soldering technique. It should only take you about 1 second or less to thoroughly solder most of the joints on this board (the components with more thermal mass, may take a bit longer…like around 1.5 seconds). I wasn’t able to see your picture that you posted (sorry for the forum limitations) but you may want to re-flow the joints on your board with a bit of added flux (preferably the “no-clean” type).
To bypass JP3, solder a wire from pin 1 on U2 to TP3. Use the thinnest wire you can find. I use “wire-wrap” wire for these types of jumpers…which is either 28 or 30AWG. You can use the wire found in a cat 5 network cable or wire from an old VGA monitor cable…that stuff is usually thin enough, from my experience. You’ll need to tin the ends of the wire first; and also tin pin 1 of U2 (solder the wire to the pin right as it exits the body of the IC). Try to fit the other end of the wire inside the TP3 hole and then solder it. If you can’t fit in in the hole then just lay it across the top of the hole and solder it down…in which case you may want to use a tiny drop of super glue to hold the wire in place on the surface of the board, but make sure you don’t get glue on the solder joint.
If you have other jumper pads that are bad, just fix them the same way. You can find out where the jumpers wires are supposed to go by looking at the schematic in the back of the manual.
Good luck!
-BrachI forgot to address the solder shorting out your power jack issue…
Are you sure that the pins of the power jack are shorted together by the solder? This would be very unlikely…the solder would solidify as soon as it hit the board, which would keep it from flowing under anything. I don’t know which pins you found connected, but 2 of the pin are supposed to be connected on the jack when nothing is plugged into it. Try plugging a power cable into the jack (DO NOT plug the other end into the wall yet…we don’t want power in the circuit yet) and then re-test continuity between all the pins on the power jack. Hopefully they are not connected anymore.
You should be able to peel off the solder drop that fell on the board without much problem. If not, send me some detailed, in-focus photos.
-BrachI had the same problem with JP3 and could see from the schematic that it was a simple jump over to pin 1 of the TL074 IC chip. Hope that helps someone.
