Discussion about the Korg PolySix synthesizer

I would suspect the actual RAM chip has gone bad.  It is IC32.  I've had 
to replace the RAM chip on more than one rebuilt KLM-367 board.

  It is listed as a Toshiba TC5514-APL3, but there are a few equivalent 
part numbers that drop-in as well.  In the USA, I get them from 
www.jameco.com, Jameco stock# 43238.  The part they sell is an Intersil 
HM6514, but it works just fine as a direct replacement.  
See http://www.jameco.com/Jameco/Products/ProdDS/43238.pdf

  These also replace the hard-to-obtain Nec uPD444c (same sort of RAM 
chip).

  It is also possible that the RAM addressing latches, IC24 and IC26, are 
bad or otherwise a trace involving them is corroded. 

Crow
/**/

On Thu, 5 Dec 2002, reidar_oz wrote:

> I bought my PolySix a few months ago and had to have the battery and
> IC31 replaced and a few tracks re-wired.  It now sounds fantastic, but
> there are a couple of problems.
> 
> First, when I turn it on, there is no sound available except a very
> low-frequency 'bloop'. I have to press the 'Manual' button and twiddle a
> few knobs to start getting a proper sound.  Is this normal?  I would
> have thought it would have some recognisable patch on power-up.
> 
> Also, the write-to-memory doesn't work well.  If I write a patch, then
> select another patch, then back to the new patch, the sound is nothing
> like what I thought I stored.  Presumably there is another chip
> somewhere that needs to be replaced.  Is this a common problem with an
> easy fix?