Archive of the former Yahoo!Groups mailing list: Vintage Simmons Drums (UK) Users Group
Subject: SDS-V switch circuit
From: jesper <jesper@...>
Date: 2013-07-31
Hi list,
I've finally dug into my SDS-V (hihat) card that was a bit temperamental
in that, that all channel LEDs was lit upon startup and that it
sometimes also played a mix of all settings between channels.
With time (heating) it returned to normalt and functioned as expected.
After tips from Micha I've taken a closer look and decided to change the
three ICs responsible for the switching. Yesterday I realised I'd forgot
to order one of them (4556). ∗crap∗ But now two are replaced and it's no
longer a christmas tree. Instead only channel 1 lights up and only
channel 1 can be chosen.
I'd get to the third IC soon too, but want to ask a Q first...
When desoldering IC1 I found PCB traces below the IC. They looked intact
but on one of the IC legs there looked to be a solder bridge/post design
modification, that came loose with the IC. I'll check the schematics to
verify soon but wanted to see if anyone here has an unpopulated card or
a picture of one and/or has the faintest idea of what I'm talking about.
∗unsure if this made any sense whatsoever∗ :S
--
electronically yours, jesper
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