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Old 20th September 2013
Lives for gear
Rob Ocelot's Avatar

Originally Posted by bigfootjim View Post
Hey Rob!
I just bought an Equinox76 that's been sitting in a music store in Texas for the last 13 years. Never been out of the store so basically new! As expected the battery is extremely low. I think I have found a few options for the battery but I need to back up the keyboard as I'm sure I'll loose everything once the battery is removed. I have found a SCSI card and an internal Hard Drive but no cables to go with them. You seem to be knowledgeable on General Music Synths (and I'm discovering that not many are!) so I thought I'd reach out and see if you had any ideas on how to back it up or where to find parts. Thanks!
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Hi Jim,

I'm not as familiar with the Equinox as I am with the S series, and even then I decided to find out as much as I could about S's out of necessity.

The Equinox's internal hard drive and SCSI option intrigue me. Most keyboards with a SCSI option also have an internal SCSI bus for a hard drive (or at least one can be adapted to the internal bus), but the HD kit of the Equinox uses an IDE drive. It's like GEM knew that finding large SCSI drives would be nearly impossible in the future.

The cable for the internal drive should be a standard flat 40pin IDE cable. Judging by the one grainy picture I've been able to find it doesn't need to be too long. They are usually grey with black (or sometimes blue) connectors. It will look similar to the floppy drive cable but will have more pins. The connectors can only go into the board one way. You might have to set the jumper blocks on the drive to make it a 'Master' drive rather than 'Slave'. most drives will have a sticker showing the jumper settings. I'm not sure if the HDD kit comes with an IDE power cable -- the service manual mentions a mounting kit and a separate power kit - I assume the power kit has the necessary power cable -- usually red, yellow, and black wires with white plugs (3.5" IDE drives usually need both 12 and 5 volts).

Does the SCSI kit have a cable to connect from the internal board to the SCSI port on the back? If not you'll need another grey flat cable, and judging by the picture it's a 50 pin cable.

Basic SCSI lesson -- SCSI chains can have up to 8 (named 0 to7) devices with your main device (computer/keyboard) usually being device 0. All the devices need an identifer, which is usually selected on the device itself. The ends of the chain need to be terminated -- device 0 usually has it's own terminator so you dont have to worry about it. The last device in the chain also needs termination. Some device like Zip and Jaz drives have a switch that can turn on termination. Otherwise you'll need a physical terminator which looks like a little cap that fits over the external 50 pin bus (different from the internal cables). Dealing with SCSI can be a joy and it can also be a nightmare. My own experience has been generally positive but there are times where a little voodoo is required -- things that should work mysteriously don't and things that shouldn't work (no termination) sometimes inexplicably do. Cable length and interference also play a role.

Unfortunately I can't help you with the SysEx but I'll keep my eyes peeled for documentation. The regular manual and the service manual don't have anything on it which is a shame. It seems that GEM's assets are now owned by Peavey so it might be worthwhile contacting them.