American Professional II Jazzmaster rhythm volume
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blaze591
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American Professional II Jazzmaster rhythm volume
The “rhythm” circuit doesn’t completely go to zero on my guitar. I can roll the thumb wheel off and I still get volume on the amp. The lead circuit does. Seems unusual. Does yours do the same? Just interested! Thanks!
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timtam
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Re: American Professional II Jazzmaster rhythm volume
The series controls on the Am Pro II JM (that replace the conventional rhythm circuit) are just a garden-variety volume and tone control, so they should function in the normal way - see schematic below. The official service manual/wiring diagram (PDF at link below) has a couple of errors - one being a missing ground connection on the bottom lug of the series volume control (the other being on the push-push coil tap switch). But the actual wiring of the guitar apparently has that lug grounded. But that would be worth checking on your guitar. The series tone control would also malfunction if it were missing.
The complex 4PDT series on/off switch is also a potential site of shorts, as it has 12 connections in a small space and is not wired particularly well (no heatshrink on bare wire at lugs).
https://www.fmicassets.com/Damroot/Orig ... master.pdf
The complex 4PDT series on/off switch is also a potential site of shorts, as it has 12 connections in a small space and is not wired particularly well (no heatshrink on bare wire at lugs).
https://www.fmicassets.com/Damroot/Orig ... master.pdf
"I just knew I wanted to make a sound that was the complete opposite of a Les Paul, and that’s pretty much a Jaguar." Rowland S. Howard.
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tammyw
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Re: American Professional II Jazzmaster rhythm volume
My guitar doesn't do that, it definitely goes completely quiet. There's a small chance it could be a bad pot that's not going all the way down.
All pain and troubles melted away like lemon drops beyond the contrails across the sky.
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blaze591
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Re: American Professional II Jazzmaster rhythm volume
@timtam @tammyw Both thanks for the answers.
The problem persisted and got progressively worse until the series volume control packed up completely and the output from the bridge pickup was seriously reduced. Figuring I would have to do something, I started to unstring the guitar and miraculously everything has started working again. Anyway, I continued to pop the scratch plate off and have a poke around inside.
The take aways
a. The quality of the stock soldering is indeed absolutely awful. Especially on the 4PDT switch.
b. The Series Volume and Tone pots are indeed grounded with a common ground.
I was unable to find a smoking gun in terms of a bad joint but honestly the wiring is so poor it could be any number of them....
The problem persisted and got progressively worse until the series volume control packed up completely and the output from the bridge pickup was seriously reduced. Figuring I would have to do something, I started to unstring the guitar and miraculously everything has started working again. Anyway, I continued to pop the scratch plate off and have a poke around inside.
The take aways
a. The quality of the stock soldering is indeed absolutely awful. Especially on the 4PDT switch.
b. The Series Volume and Tone pots are indeed grounded with a common ground.
I was unable to find a smoking gun in terms of a bad joint but honestly the wiring is so poor it could be any number of them....