Marshall JTM45 Tremolo -- Vintage repro build

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xtian
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Marshall JTM45 Tremolo -- Vintage repro build

Post by xtian »

A new client from Los Angeles asked me to assemble his Super Tremolo Amplifer. According to my client, he spent $800 on knobs and $700 on KT66s alone!

I'm trying to figure out the wiring of the footswitch on the tremolo turret board. Any photos I can find show two wires from the footswitch going to the turret board--one to the Collector, and one to the empty turret below. But I can't see what that mystery turret is connected to, and the schematic does not shed any light. Any help?

This is a photo of the actual board he sent me, with my notes:
IMG_1485.jpg
Schematic:
jtm45_lead_45w.pdf
Unknown.jpeg
Bluesbreaker Chassis Inside #7.jpg
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martin manning
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Re: Marshall JTM45 Tremolo -- Vintage repro build

Post by martin manning »

Schematic shows the foot switch between the collector and the intensity pot wiper. That empty turret is the pot wiper, I think.
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xtian
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Re: Marshall JTM45 Tremolo -- Vintage repro build

Post by xtian »

Ok, so two wires run to the foot switch, these two wires make the connection between transistor and pot wiper then ftsw is closed. Right?
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martin manning
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Re: Marshall JTM45 Tremolo -- Vintage repro build

Post by martin manning »

That's the way I see it on the schematic, and the photos seem to agree.
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Reeltarded
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Re: Marshall JTM45 Tremolo -- Vintage repro build

Post by Reeltarded »

https://www.marstran.com/1987T.gif

damned ipad undo killed me again!

50/T is same
1573B98A-873B-4530-8608-A4D24BC91F55.jpeg
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xtian
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Re: Marshall JTM45 Tremolo -- Vintage repro build

Post by xtian »

Project finished and shipped. Went really well, even considering it took over twice as long as I estimated (23 hours total). Glamor shots and video below.



IMG_1528.jpg
IMG_1538.jpeg
IMG_1542.jpeg
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Colossal
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Re: Marshall JTM45 Tremolo -- Vintage repro build

Post by Colossal »

Looks and sounds killer. Very nice work! Big, fat low end.
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Reeltarded
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Re: Marshall JTM45 Tremolo -- Vintage repro build

Post by Reeltarded »

Great job! Lets cascade it and....
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ViperDoc
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Re: Marshall JTM45 Tremolo -- Vintage repro build

Post by ViperDoc »

Cool! What’s that socket isolator on V1 called?
Just plug it in, man.
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xtian
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Re: Marshall JTM45 Tremolo -- Vintage repro build

Post by xtian »

ViperDoc wrote: Tue Mar 22, 2022 6:49 am Cool! What’s that socket isolator on V1 called?
No clue. Was supplied by client.
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martin manning
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Re: Marshall JTM45 Tremolo -- Vintage repro build

Post by martin manning »

Very nice! Looks and sounds great!
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Reeltarded
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Re: Marshall JTM45 Tremolo -- Vintage repro build

Post by Reeltarded »

It is a stunning amp. I always love the chop of the trem on good /T models.. and this one is excellent!
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angelodp
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Re: Marshall JTM45 Tremolo -- Vintage repro build

Post by angelodp »

Now that is a sight to behold, simply superb.
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