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accutronics geneva reverb tank and reverb amp.

darren adcock

Sep 26, 2016
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Hi all I got given a reverb tank with an attached reverb amp and I would like to see if I can make it work and was hoping you guys could help.

The reverb tank reads: accutronics, geneva, ILL, pat 2982819 3106610, made in USA.

The reverb amp has got RA-1C written on it. I couldn't find out where it came from as it was bought to me in a box of other stuff from practice rooms that had been left.

Thanks

JQDOxdN.jpg
5eeR2VS.jpg


A9thMoG.jpg

wv0pgDR.jpg
 
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(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Jan 21, 2010
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Essentially you'll have 2 amplifiers and a mixer.

One amplifier drives the springs, another amplifies there output from the other end of the springs, and a mixer determines how much signal comes from the original source vs through the reverb unit.

Figuring out the topology of the board is the first trick. If you can locate where the mixing happens, that will generally point out which amplifier is used to drive the reverb springs, and which is for the output.

The transistors with the heat sinks are probably used to drive the reverb, and those on the other side are probably the signal amp for the output of the reverb. The small trimpot is probably used to trim the gain so that the signals being mixed are the same level. The mix control is probably not on this board.
 

darren adcock

Sep 26, 2016
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Cheers Steve.

That helps loads. I'll firstly try and draw up a schematic and get a component list together.
 

darren adcock

Sep 26, 2016
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Made this schematic today, i'm sure there'll be mistakes. 1-4 connection nodes lead to the tank. 5-10 break out the other side of the board. Not really sure how to work out which does what if you don't mind helping?
NoMO0H7.jpg
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Yeah, there's a few errors :)

Are the points labeled "F" connected together? If so, 4 will be a drive for the reverb unit (other side will be ground)

1/10 (near Q5) is probably the input from the reverb.
 

darren adcock

Sep 26, 2016
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hey Steve, thanks.

first ever attempt at drawing a schem from a circuit. :)

Yes points "F" connect. Is there a more standard way of annotating this?

1/10 is actually 11, doh, if you mean the point closest to Q5?
 

darren adcock

Sep 26, 2016
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ok so got given a leslie speaker at same time so thought maybe this is from a hammond?
 

darren adcock

Sep 26, 2016
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Hi Steve. I will be relying you to mostly figure this out, just wanted to say really happy to just build a fresh circuit that's tried and tested instead. Might be frustrating as the schem isn't right, save a lot of work
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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If advise you to Google for circuits people have used. My knowledge is not based on actual experience :)

In any case, it's always worth familiarizing yourself with the available options.
 

darren adcock

Sep 26, 2016
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will do cheers!

I've become to realise just engaging in any way with any part of electronics is all part of learning.
 
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