I'm not a super expert tech but can solder

[dr.c]

I would like to have time to answer at my rythm, by times...

Ots normal there is sound, the rams you took away were the program ones, not the sound !

You should look around the clock, maybe something wrong. I don't know, now...

[rev mex]

Great news Dr. C,
I purchased a logic probe and began snooping around the CPU and RAM modules.
I found that RAM (13K) pin 20 was dead. I traced pin 20 back 13E (NAND Gate 4023) pin 9 and did get activity from the NAND Gate.
I'm thinking that there is a broken connection between these two points.
Should I be able to get a "beep" sound when using my multi-meter to check continuity at these two points? I don't get a connection.

-rev

[Dynamikk]

Hi Rev,

Did you solve the freeze issue?
I have a similar issue with my Drumulator...but for me it freezes when I press the Copy/End button.
Also after a freeze I have to clear the memory due to the Bad message (not all of the times).
The battery has been replaced and all the caps are ok...so all of the other functions on the Drumulator works fine except the Copy/End button.
I had an idea that the scratch pad RAM wasn't working 100% but I still haven't replaced them...I need to do some more measuring.
I've also swapped around the two RAM chips but that didn't help.

Is there anyone that know if it's possible to get hold of the Debugging Eproms?
I think those would be a very helpful guidance in this kind of situations.

/Dynamikk