[sdiy] Odd MKS-70 Behaviour....

[WeAreAs1 at aol.com]

In a message dated 2/3/04 2:43:23 PM, buchty at cs.tum.edu writes:

<< > Every time I shut the machine down, the MIDI parameters get scrambled.
> For example, the control channel becomes 1X (literally what the machine
> reads!!), and I get similarly odd results on both the individual A and B
> channels. While I CAN go through this little routine upon startup
> forever and ever, I am generally concerned that this might signal a
> bigger problem on the horizon.
>
> So far, the only things I can think of are:
>
> 1. The backup battery is on the way out;
> 2. Bad RAM chip;
> 3. Partially scrambled software. >>

I think it's odd that the MIDI parameters get messed up, but the voice 
programs don't (at least you didn't say anything about the patches being damaged).  
A dying battery would affect all data, not just the MIDI parameters.  I don't 
have MKS-70 schematics handy, but I wonder if it has separate RAM chips for 
the voice patches and for the global stuff (the MIDI params, etc.).  How many 
SRAM chips are in there on the CPU board?  I might suspect that one of them is 
bad.  Do you have a schematic set?

Michael Bacich