I just did that a half hour ago on an Ensoniq keyboard. The battery is soldered in, and someone had replaced it and tore the trace up under the battery. I installed a coin cell holder, so now anyone can buy a new battery at Radio Shack and snap it in without soldering. But to get the circuit restored I had to run a small wire from the pin of the holder over to a resistor across the board.
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Originally posted by g-one View PostAre you sure it was wire and not a (ribbed) tube? They will often rip out of the board if you don't have the component perfectly desoldered.
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Originally posted by daz View PostYes ! No doubt that was it, makes much more sense. It never occured to me but that must be it. They came out on ALL of them tho, and i didn't do anything crazy and desoldered them as well as i could. But i could not get it all no matter what i did so i had to melt one side and tilt the cap then do the other. Maybe it could be done but i had no idea and they were really in there big time. Never seen that before and I've dealt will plenty of double sided boards. Anyways no big deal. Just a few pieces of wire to make my own "traces" as enzo just mentioned and all is fine.
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Originally posted by nosaj View PostAnybody notice caps in one schematic are rated for 350v and the other at 400v?
nosaj
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Just the fact that there is no wiggle room as far as voltages go.
Quote: Sounds like there may be a connection failing between the filter caps and the B+ line. It seems to be getting progressively worse, maybe from board flexing? It went from 350V to 325V and now you have the harmonizer note.
As you say, it could be a feed through for the double sided board, but it could also be a cracked pad or trace.
Resistance checks from main filter caps may help, to the ground connection, between the 2 caps and to the B+ line.soldering stuff that's broken, breaking stuff that works, Yeah!
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Those caps in the power supply are stacked in a "totem pole" (series) configuration. So you have the equivalent of a 700V cap. for each of the 3 sets. None of them should be getting near 350V, so you don't need to worry about that. C6 & C7 = 50uf 700V, likewise for C8 & C9, and C11 & C12Originally posted by EnzoI have a sign in my shop that says, "Never think up reasons not to check something."
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Originally posted by g-one View PostThose caps in the power supply are stacked in a "totem pole" (series) configuration. So you have the equivalent of a 700V cap. for each of the 3 sets. None of them should be getting near 350V, so you don't need to worry about that. C6 & C7 = 50uf 700V, likewise for C8 & C9, and C11 & C12
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For sure it was leakage and not adhesive? Very strange for a 1 yr. old, but maybe a bad run of caps.Originally posted by EnzoI have a sign in my shop that says, "Never think up reasons not to check something."
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Originally posted by g-one View PostFor sure it was leakage and not adhesive? Very strange for a 1 yr. old, but maybe a bad run of caps.
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