I've got a Drumtraks on my bench that is driving me nutty. Everything works fine (all sounds, midi control, etc) but as soon as I try to record a pattern, it will act very glitchy like in your video. Sometimes it works fine, but usually it doesn't. Extremely temperamental.
I’m concerned you may still have a bad RAM IC, and the problem is simply not manifesting itself in the same way because it’s in a different socket now. Personally, after discovering that the problem seemed to go away after swapping RAM between sockets, I would go ahead and replace all the RAM. Great video, I’m an amateur repair guy and I’m not professing to be any authority on this stuff.
Thanks! It's made me wonder. I've programmed patterns at locations 00, 01, 26, 51, 76 and all patterns get saved correctly. So I'm still not sure what's up.
Are you sure those were RAM chips and not ROM chips? RAM from this era was seldom packaged in 28 pin packages. If they were ROM then they absolutely have to be in a certain socket in order for the ROM to show up at the correct address.
Absolutely, there's one eprom chip for the program data. Your message made me wonder, do I yet have a bad ram chip? I've programmed patterns at locations 00, 01, 26, 51, 76 and all patterns get saved correctly. So I'm still not sure what's up.
