JCA50h channel switching problem
Posted: Tue May 18, 2021 9:04 pm
Hi, new member here. I registered to seek help with my peculiar issue. I recently purchased a dismembered Jet City 50h(PT went out I figure, as it was the only part that wasn't included in the transaction), all wires were cut as well. I saw an amp that I hoped could be brought back to life so I bit. Long story short, I succeeded in my quest and returned it to a functioning state...all accept the footswitch actuated channel selector.
The footswitch itself turns on and off(and to test that it wasn't that, I bought a new one as well, it too turns on and off) but does not switch channels. One can rudimentarily change channels by pulling out the jack(where it defaults to OD, jack in equals Crunch), or as I discovered, in tandem with a shorting jack, wire up a SPDT and use that instead, which works. The goal here is that I want to have my cake and eat it too; I want the convenience of the footswitch, but also the front mounted switch, though I'm not happy with just the switch.
So this is my quandary. Why would the SPDT switch work, but the footswitch not? The footswitch is getting power. The PT is a Mercury Magnetics drop in, and I followed the schematics(best I could) and even contacted MM about the "accessory" wires(which power said footswitch) to verify that I indeed had connected the right wire to the right place on the PCB, again every thing was severed and there wasn't a whole lot of help offered via the Jet City Facebook group I joined in vain. Every image I can find of the JCA50h PCB shows just 2 wires connected to a normal jack, nothing extra. Apparently no one else on the internet has had my problem, or at least as far as I can tell. Maybe there is a core wire I'm supposed to wrap along with the accessory wires, I dunno, the MM Tech I talked to didn't say anything about it. I know the MM PT was not a 100% mirror of the original PT, that's for certain. Some wires were needed to be spliced together, some weren't used at all, and they were not color matches of the wires left on the board the previous owner was so nice to leave for me.
Any help is greatly appreciated!
The footswitch itself turns on and off(and to test that it wasn't that, I bought a new one as well, it too turns on and off) but does not switch channels. One can rudimentarily change channels by pulling out the jack(where it defaults to OD, jack in equals Crunch), or as I discovered, in tandem with a shorting jack, wire up a SPDT and use that instead, which works. The goal here is that I want to have my cake and eat it too; I want the convenience of the footswitch, but also the front mounted switch, though I'm not happy with just the switch.
So this is my quandary. Why would the SPDT switch work, but the footswitch not? The footswitch is getting power. The PT is a Mercury Magnetics drop in, and I followed the schematics(best I could) and even contacted MM about the "accessory" wires(which power said footswitch) to verify that I indeed had connected the right wire to the right place on the PCB, again every thing was severed and there wasn't a whole lot of help offered via the Jet City Facebook group I joined in vain. Every image I can find of the JCA50h PCB shows just 2 wires connected to a normal jack, nothing extra. Apparently no one else on the internet has had my problem, or at least as far as I can tell. Maybe there is a core wire I'm supposed to wrap along with the accessory wires, I dunno, the MM Tech I talked to didn't say anything about it. I know the MM PT was not a 100% mirror of the original PT, that's for certain. Some wires were needed to be spliced together, some weren't used at all, and they were not color matches of the wires left on the board the previous owner was so nice to leave for me.
Any help is greatly appreciated!