[sdiy] Andromeda A6 repair?

[Barry Klein]

Hi all,
An update on my progress on this....
Go to Gearslutz.com to see the details.  There are two threads - one on fixing the boot problem and another on the OS.
There are two other key players in this game - one a pretty sharp hardware guy and another a sharp software guy (named Sharp too).
One fix seems to be the resonator on the display.  Replace it with a  3Mhz xtal.  as the resonator can become intermittent.  If it does it may cause an interrupt in the serial signal to the main pcb and stop everything.  This may be my unit's fault but I couldn't see it die with my scope.  I now have an xtal and will replace it to see.
In the meantime I have fixed an open via on the main pcb and a later-failing via at the transformer input pin of the supply.
I have pulled the flash part and finally made a good copy of it once I gave up on a cheap programmer and spent $150 on a better one. (GQ-4X).
I used a DVM and buzzed all address/data lines and found no issues. Put in headers for a logic analyzer.  Obtained a PE Micro debugger that plugs into a BDM header on the main board.  It didn't work for me and my unit doesn't work so I sent it to the software guy to try on his working synth.  We should know shortly if it works.  May have to do a little hardware tweaking.
He intends to modify the OS and improve upon things - adding functions, fixing bugs.  I just want to nail this boot to splash screen crap.  I have replaced the CPU and NVRAM with no change (had flakey boot).  But when I replaced the SRAM chips I couldn't get past the splash screen - and even that was intermittent.   Giving that is intermittent I am now suspecting the xtal could be the fix as the screen boot may be the responsibility of the 80C52 with the LDC module and independent of the main pcb.
So I feel I'm close.  Looks like my flash image was undamaged.  I am going to load a newer one into the chip with my programmer.  Been an emotional but fun challenge so far.
My wife made me move stuff in the garage so she could get her car in.  This now prevents me access to the synth!  Too much stuff.
Much of it is magazines.  Can't decide whether to try and keep - by putting in an unpurchased storage shed - or sell/give away/trash.  I guess the ones with thumbdrive history backups for sale or accessible online go first - like 73, QST, Circuit Cellar, older computer mags.  Still leaves Modern/Popular/Radio Electronics, Nuts and Volts, Keyboard, Elect Musician, and a bunch of photography magazines and stuff.  Keeping Polyphony BTW.

Barry