[sdiy] BP Electrolytics & Obscure Solina ICs?

[Roy J. Tellason]

On Sunday 06 May 2007 18:21, Michael Ruberto wrote:
> The more distressing situation with the console is these:
> http://i108.photobucket.com/albums/n13/somnium7/gear/toa_input_amp.jpg
>
> See the big black cube? It's a discreet amp module. Pure unobtainium. Some
> of these have burned out. The burned power resistors near them and the
> cracks in the potting make this pretty apparent. I'm now cannibalizing
> sections of the mixer to fix more mportant sections because of these
> things. Today I got curious and took one of the line-amp units outside with
> a hammer and a screwdriver. There isn't much inside! Two unmarked TO-220
> transistors, a HA-12017, and a few passives. I'm thinking I might be able
> to cobble something together to use as replacements!

That's exactly what I did when I first hit the situation where I needed 
a "keyboard op amp" for an ARP 2600,  I built one,  on a small hunk of 
perfboard,  using a pretty standard op amp and a dual FET like I'd seen them 
do in some other stuff (this was back before FET-input op amps were as common 
as they later got to be  :-).

-- 
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space,  a critter that can
be killed but can't be tamed.  --Robert A. Heinlein, "The Puppet Masters"
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Information is more dangerous than cannon to a society ruled by lies. --James 
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