Rhodes Chroma Polaris

> From: Robert Weigel
> 
> Thanks..yeah...I know buttons fail :-).  But...I'm talking 
> about ALL of them.  Literally..every one has failed within a 
> matter of hours after working great ...completely great...for 
> 20 years!  hehe.  Yeah I know other people have a button or 
> two fail here and there. 
> <snip>
> Yet..what am I to think?  ALl of the ribbons look perfect. Like I
> say..continuity all the way down to the flat on every line!   I
> seriously..believe this thing should be in a 'freak occurance 
> museum' someplace. hehe.  I mean just the membrane panel.  
> Give me another one and I'll take the chroma polaris for my 
> contribution :-)
> 
> But I'd say much more likely..somehow there is a weak point 
> under the panel somewhere and all the data lines severed 
> somehow.  Even though I..never pulled or anything on anything 
> that should have done that..ahem..

Do you have a scope? This should be pretty easy to diagnose with one.
However, the SWSTB lines are open-collector, so it's helpful to touch them
with a resistor to +5V just to make sure the driver is working correctly.

-- 

Ciao,               Paul D. DeRocco
Paul                mailto:pderocco@...