[sdiy] strange strange SAJ110 divider issue?

[Bob Weigel]

Just an adendum to this.  I see that on the variac I can cause the 
chattering dividers to work/not work by lowering voltage to 110 or 100v 
zone.  What the heck is going on here?  They *are* supposed to 
work...these chips..at 10 or 11 v...right? How come they all fail on the 
same divider?  What a nightmare.  As I was trying to get a couple keys 
to work that had bad contact busbar alignment I managed to twak 
something and knocked out the op amp, transistor and burned the 47 ohm 
resistor.  hehe..so now I have to get that stuff in there and try to 
even get it making sounds again.

Bob Weigel wrote:

> I tested a whole bunch of SAJ110's in the crumar organ we just did.  
> They work perfectly in there.  So ...I finally pulled the old solina 
> string ensemble back out.  Put a tested chip in a socket I'd installed 
> that was on a problem chip location (number 4).  The...same divider on 
> pin 11 is still garbled.
> I can unhook the whole trace!  Still..the..same garbled sound.  I have 
> -10V instead of the -12V the diagram says should be there. However the 
> DOCS on the chip say absolute max rating is -11V there!  It's smooth.  
> No ripple or fuzz visible on the scope.
>
> All the other outputs seem to be working fine on that chip.  Though 
> other dividers are also having problems.  Very puzzling.  Has anyone 
> ever seen a phenomena like this? I mean it's clearly dividers that 
> work in another machine so something about the power supply would seem 
> the logical first guess but is it possible there's something I'm not 
> seeing just causing one line to do that on every chip I put in there?? 
> Cap esr's seem fine.  I even paralelled another cap just to be 
> sure...-Bob
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