[sdiy] Parts ID request

[harrybissell]

I doubt very seriously they are switched capacitor filters... the age is
too old... they are surrounded by 741 opamps and maybe a TTL chip ?

5% resistors... etc.

I'd guess they were homemade modules... maybe expo converters that
would benefit from the epoxy potting.

(good cop)

Are they YOUR modules ?  If you posted really detailed pictures of both sides
I'd be willing to try and trace the schematic to the point of implying what is

inside...    ~or~

(bad cop)

we could send them downtown to see the "old crow" who has a way of
getting the information out of stubborn epoxy modules like you...

...but it aint gonna be pretty...

H^) harry

John Loffink wrote:

> I know this may be a long shot, but here goes.
>
> Does anyone recognize the potted elements in the photos at the below link?
> These are probably 4 or 8 pole switched capacitor filter elements, circa
> 1976-1980.  The cans are not labeled.
>
> http://www.wavemakers-synth.com/filter_cans.html
>
> John Loffink
> The Microtonal Synthesis Web Site
> http://www.microtonal-synthesis.com
> The Wavemakers Synthesizer Web Site
> http://www.wavemakers-synth.com
>
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