Rhodes Chroma Polaris

> From: Robert Weigel
> 
> Paul, the reason 5 isn't tuning is still a mystery. I 
> swapped all the chips.  No result.  However the reading I was 
> getting... that was on the wrong resistor.  They changed the 
> pattern I see.  The envelope is showing up if I get it on the 
> right resistor :-).  It looked like a clear pattern but for 
> some reason on 5 they changed it! I couldn't see the 
> writing... anyway I figured probably the hard wired leg 4053 
> chip but no dice.  Still doesn't tune until I turn it 
> on..then..I find out ..it's tuned.  Whaaaaatever.  I dunno.  
> I need to see the code i guess to know what routine it goes 
> through on the tuning.  lol

The order in which things are tuned is channel 1 through channel 6. Within
each channel, it tunes pitch 1, pitch 2, width 1, width 2 and cutoff. The
Tune switch LED is on while tuning the pitches. You can usually tell where
the process failed by forcibly enabling that channel and disabling the
others, and then seeing whether the oscillators are in tune, and whether the
pulse width goes from 0% to 99% with a proper square wave at 50%.

> PS I checked the tune buffer in also and it looks about the 
> same on all channels.  Actually 5's signal looks just a hair 
> hotter for some reason.  5% maybe.  4's is weakest I think 
> and it works fine.  Maybe I should..attenuate it some? Too 
> weird.  5's light is always off after I tune when I do lower 
> function E....

Don't bother. There's nothing wrong with the signal being a little hotter.

-- 

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