Search found 795 matches

by Rasputin
Wed Sep 21, 2016 12:08 am
Forum: HELP!
Topic: AX-80 O.S. hacking co-op?
Replies: 89
Views: 22269

Re: AX-80 O.S. hacking co-op?

I had always assumed that David Cockerell had something to do with the AX80, but it looks like you may be looking for 'Tamaki San'. Long shot, but it seems that Toshio Tamaki has an Etsy page and a Twitter: https://www.etsy.com/people/toshio , https://twitter.com/september3030 Anyone know him or th...
by Rasputin
Mon Sep 19, 2016 6:48 pm
Forum: HELP!
Topic: Service Manuals and Schematics!
Replies: 105
Views: 192291

Re: Service Manuals and Schematics!

Ensoniq VFX, VFX-SD, SD-1: Service Manual https://drive.google.com/open?id=0B44NKm9yPA1baU1kWWRGdjhickk Ensoniq - Service Bulletin #13 (keyboard problems) https://drive.google.com/open?id=0B44NKm9yPA1bV0wwYTN4akNNWkE Schematics https://drive.google.com/open?id=0B44NKm9yPA1bRURVMDQtUF9JYWs These are ...
by Rasputin
Sat Sep 17, 2016 4:59 am
Forum: HELP!
Topic: General Troubleshooting Logic
Replies: 16
Views: 3023

Re: General Troubleshooting Logic

CPU datasheet Might help. Vcc is the pin at the "bottom" right (pin 33) and is probably being fed +5V. Looking at the schematics, some components that might be worth checking in to would be C75, C76, C80, C77, C78 and maybe Q4. If not the CPU, probably IC60 (MB62H133) or one of the two ROM chips. B...
by Rasputin
Sat Sep 17, 2016 4:24 am
Forum: HELP!
Topic: General Troubleshooting Logic
Replies: 16
Views: 3023

Re: General Troubleshooting Logic

He gave up after that, and sold it to me. Normally the first thing I would check is power because that's just where everything starts, but before I open it up, and recheck everything I was thinking of how best to spend my time. Time best spent? Making a listing on eBay :D Nah, I wouldn't be able to...
by Rasputin
Fri Sep 16, 2016 6:39 am
Forum: HELP!
Topic: General Troubleshooting Logic
Replies: 16
Views: 3023

Re: General Troubleshooting Logic

What makes an electronic device display random behavior? Bad power, almost always. Other than that, interference. But usually that's a design flaw that's remedied during the engineering (or re-engineering) stage, so it rarely crops up in production models unless somebody did something to it, like r...
by Rasputin
Wed Sep 14, 2016 8:23 pm
Forum: HELP!
Topic: AX-80 O.S. hacking co-op?
Replies: 89
Views: 22269

Re: AX-80 O.S. hacking co-op?

Good news: MIDI SysEx out is now working and seems stable.

Bad news: MIDI SysEx in is still doing nothing productive, we still have no patch editor for tape dumps, and I still only have access to the Revision K ROM. <ahem, hint hint>
by Rasputin
Sat Sep 10, 2016 2:35 am
Forum: HELP!
Topic: Esq-1 glitching
Replies: 4
Views: 1021

Re: Esq-1 glitching

If I could get it for $100, I'd personally hop all over that gamble. But it all depends on how confident you are in your tech skills, or if you know someone competent and affordable local to you. I think all guesses so far are on the money, but you never know. I'd highly suspect a voltage regulation...
by Rasputin
Sun Aug 28, 2016 1:51 am
Forum: HELP!
Topic: AX-80 O.S. hacking co-op?
Replies: 89
Views: 22269

Re: AX-80 O.S. hacking co-op?

Just got an ax80 and I can't begin to say how much I'd love to see Sysex implemented in it. Hoping that this will turn into reality. Seems very doable. I suspect that getting an editor wouldn't be too hard either. Does midiquest offer any generic editor that could be customized for an ax80? That ap...
by Rasputin
Sun Aug 28, 2016 1:20 am
Forum: HELP!
Topic: AX-80 O.S. hacking co-op?
Replies: 89
Views: 22269

Re: AX-80 O.S. hacking co-op?

Dumped and disassembled the CPU mask ROM yesterday. I don't have it entirely figured out yet as there's some unorthodox stuff going on by the looks of it, but it seems to do much less than I would have thought. The interesting points are that it drops into 64K mode by default, so that could potentia...
by Rasputin
Thu Aug 18, 2016 2:45 am
Forum: HELP!
Topic: Best way to repair broken PCB tracks?
Replies: 21
Views: 7027

Re: Best way to repair broken PCB tracks?

I saw a You tube video on this topic a while ago ... there is a special conductive adhesive tape that only conducts in one orientation. For example, if you tear off a strip of tape, it only conducts along the length of the tape but not across the width. This means you don't short out adjacent wires...
by Rasputin
Wed Aug 17, 2016 7:48 pm
Forum: HELP!
Topic: Best way to repair broken PCB tracks?
Replies: 21
Views: 7027

Re: Best way to repair broken PCB tracks?

I can sympathize with it not being worth your time, but given that those PCBs don't exist anymore then I hope you'll at least consider donating it to somebody up for a crazy challenge instead of tossing it into a landfill.
by Rasputin
Mon Aug 15, 2016 5:57 pm
Forum: HELP!
Topic: Best way to repair broken PCB tracks?
Replies: 21
Views: 7027

Re: Best way to repair broken PCB tracks?

Here´s a closer view. No clock signal from the resonator is therefore arriving at the secondary CPU (IC6). Frozen behaviour and blank LCD screens seem to happen a lot to the DX7S and the mkII, so this is one probable cause. After some research I bought new RAM chips and a 27C256 EPROM to burn befor...
by Rasputin
Mon Aug 15, 2016 1:32 pm
Forum: HELP!
Topic: Best way to repair broken PCB tracks?
Replies: 21
Views: 7027

Re: Best way to repair broken PCB tracks?

This is the DM board from my DX7S. It was either caused by the weight of the keyboard frame that bent and cracked the PCB or by overtightning the mounting screws. Anyway, the front panel doesn´t respond and the screen is all black squares now. I count 25 broken traces. Soldering wire bridges to the...
by Rasputin
Mon Aug 15, 2016 12:33 pm
Forum: HELP!
Topic: AX-80 O.S. hacking co-op?
Replies: 89
Views: 22269

Re: AX-80 O.S. hacking co-op?

So I take it that it's not easy to split a bank into individual patches? It's super easy. It would just be a hassle to try to create/merge/copy/edit patches without a patch editor which is where we stand now. Creating a serviceable patch editor should take no more than a day or two for anyone that ...
by Rasputin
Sun Aug 14, 2016 9:21 pm
Forum: Samplers
Topic: Here are the Emax II Library samples!
Replies: 51
Views: 110735

Re: Here are the Emax II Library samples!

Psst...

Emax I/II samples can be found here... in their original formats.