Tascam Midiizer MTS-1000 Manual & Cables

I have a source for old e-proms as i get them in for my day job, usually fixing up old control equipment, the trouble is getting them programmed. If you could find a tech company with a e-prom reader they would be able to suck the program out of a good e-prom and load up a new one. LINK to e-prom

Alan.
 
Yes. Whenever I get a new piece of equipment from the 80s or 90s, I tend to back up the EPROM and run the system off a copy to make sure it worked. So I could easily do this - assuming I had access to a working MTS-1000 :-/
 
Never got any reply from Tascam Germany.

As I recently wanted to update my Kurzweil K2000 sampler keyboard firmware version I looked around for some EPROM replacements. Kurz OS 3.87C costs around £40 with postage for a pair of EPROM's on EBay, WTF?

Anyway I found an online source with the BIN files for many old '90's keys & FX's firmware /EPROM's DBWBP.com - Synthesizer ROM archive

So the cheaper option is I bought the EPROM reader / writer for £28 & then buy a pair of OTP EPROM's for £3-4 instead, plus I get to back up the Midiizer EPROM's afterwards.

The Midiizer EPROM datasheet
Hitachi Semiconductor - datasheet pdf

I'm assuming this OTP will do the job in replacing the Midiizer EPROM?
AT27C256R-70PU MICROCHIP, EPROM, One Time Programmable, 70 ns, 32K x 8bit, 256 Kbit, 4.5 V to 5.5 V, DIP-28 | Farnell element14
 
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Earlier in the thread someone was saying that their Midiizer had two EPROMs, a 27C256 and a 27C512. If that's true, you'll need one of each type, since the 512 is twice the capacity. I've not tried using OTP EPROMs personally, I prefer the UV ones with the window because I can wipe them and try again if something went wrong.
 
I've managed to read the two pairs of Tascam Midiizer MTS-1000 EPROM data & saved them as BIN files.

WORKING

C 1.22 (control PCB top) HN27512G DIP28
M 1.21 (main PCB bottom) HN27C256G DIP28

FAULTY UNIT

C 2.00 (control PCB top) HN27512G DIP28
M 2.00 (main PCB bottom) HN27C256G DIP28 (This might be faulty as it doesn't appear on the LCD screen but it's code seems similar to the M 1.21 version?

I've ordered the cheap OTP eproms just to see if I can get them working on the Midiizer but will buy an UV eraser to wipe & reuse the 10 erasable EPROMs that I already have.
 
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Thanks. I can't see anything blatantly wrong with the V2 files, I can see text strings in the C chip files so it's not like the entire thing is garbled. The M chip doesn't really have anything human-readable in it but structurally they look similar. Good luck with the programming!
 
Burned a new pair of C 1.22 / M 1.21 files but my non working Midiizer only recognises the C 1.22 chip, also tried the old working M 1.21 chip with no luck.

Then I fitted the non working chip pair C / M 2.00 & they are recognised in my working Midiizer which originally had the earlier software version chips.

Looks like there's a problem somewhere with the non working lower Main PCB, that means swapping the boards out completely!
 
I should point out I have never seen a circuit board of a Midiizer, but if this makes sense, have a very close look at the soldering on the e-prom socket, use a magnifying glass and check that the solder has not got a hairline crack from removing the e-proms, I would touch the solder with a soldering iron anyway just to check it's not a small crack or a dry joint.

Alan.
 
Better later than never, as the historical importance of these earlier forum threads (and the units they supported) shouldn't be relegated to the rubbish bin.

As far as old technologies are concerned, yes- it's possible that an EPROM could go bad with age, certainly older backup batteries can, but the number one thing that will fail statistically is capacitors! Silicon-based devices are actually pretty stable, and unless overstressed by too much current demanded of them, or an overvoltage condition, they can last decades in a well designed circuit. Resistors fair well also, and certain film and ceramic capacitors can as well, but electrolytics are generally notorious for "drying out", or requiring sustained voltages or application of varying voltages to "fully form".

In an earlier post altruistica had mentioned that his Non-Working MTS-1000 suddenly sprang back to life. It's not unheard of for capacitors to do this- to be marginal until subjected to something like an actual in-circuit condition for a while.

There are many other conditions that are tricky in actual electronic devices, such as thermally related failures (usually intermittent ones) which might come from flaky, cracked or marginally "cold" solder joints (solder, if viewed in the very large timescale is actually a liquid- it can "cold flow", much like glass). Oxidation is obviously another thing that can affect older circuits- scrubbing or chemical cleaning of header pin connectors is advisable, for example, or occasionally (and very carefully) removing and re-inserting removable IC's from their sockets (to "freshen up" the contact pins) can be helpful.

For my money, I would start troubleshooting NW units in the following ways:
1. "Idiot check" for the obvious: unit properly plugged in, power switch on, fuses not blown, interconnect cables properly made, "volume" pots or other controls such as switches in a "neutral" state, etc.
2. Check for bulging, or leaking electrolytic capacitors (look for a shiny or sticky residue around the capacitor ends) - if necessary remove a suspect electrolytic and either replace immediately with a new one or test it with an LCR meter before returning it to its in-circuit position (always observe polarity when replacing polarized electrolytics).
3. Look for component "browning" of resistors which indicates an overheating condition. Likewise check the areas of the PCB's themselves for "browning" , which may indicate an overheating condition, particularly near higher-powered circuit components, such as voltage regulators.
4. With circuit turned on, very carefully feel the tops of IC's etc. for too much heat (do not ever touch bare metal, such as conductive leads, pins etc., or the backs of voltage regulators- which are often carrying a voltage). Better yet, use one of those non-contact Infra-Red thermometers, and check for elevated temps of particular devices including diodes, caps and resistors, as well as IC's.

Beyond these initial checks (which can be made by anybody with minimal tools required) solutions would probably require tech-like troubleshooting with scopes, meters, signal generators, or other more sophisticated gear. Occasionally some correctly applied intuition with a complete and accurate set of schematics can yield results on its own, but usually some knowledge of the "Theory Of Operation" of a given circuit design will be required.

So speaking of the practical, did anyone posting here manage to off-load the EPROM image files for the MTS-1000 and save them to hard disc? If so would you please consider posting the ".bin" files to a website like someone here had suggested? At least the rest of the world could possibly reconstruct future EPROMS for those of us who don't have an EPROM reader/burner. Thanks for all your help.
 
Does anybody have Still the schematics for the PW 5MD ? Thank you! ! ! !

Hi Mentholarnold, I sent you an email with a link to the forum threads with the detail / layout to make a cable last week.

Meanwhile I actually got my faulty Midiizer lower main PCB working, the faulty machine recognised both EPROM chips & shows accessory 2 is now online on the display. I've not tested it yet properly but it appears to boot up as normal.

I had previously cleaned all the lower PCB countless times with IPA for hours, then I removed all the solder from the EPROM & re-soldered & re-flowed all the chips & components around the EPROM & battery area including U1 HC63B03YP, a 64pin IC with very close pins, not SMD but smaller pitch than usual DIL size & gave it all another clean with no luck.

Disconnected the RAM memory card ribbon connector & had removed the old backup battery when cleaning, which I had taken from the working machine.

I was surprised when it suddenly worked without the RAM memory card & battery connection. I'm not sure what RAM memory card the Midiizer takes but it looks similar to a user patch card like used on Roland or Ensoniq synths at that time?

Now I'm frantically looking round for all the original screws & inside parts to put these two machines back together LOL! Then next I'll make a PW 5MD cable & fit some new EPROM's.
 
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hello i have a related question. i have two MSR 16's synced with custom made 20' d sub cables to a midiizer. long story short i can't seem to get rid of the sync sound bleed in the audio, however faint. its everywhere and only occurs when both d sub cables are connected to the machines. i could go on and on, but i'm just poking around to see if anyone else has had the same problem. i believe my tech made the cables from specs in the MSR 16 manual, and I now have been trying to find out if the shielding on pin 7 might have not been specified in the MSR 16 manual.
i also did notice a while back there is only one way for the d sub cables to be connected correctly for the tape machines to properly sync, even though both ends look the same (d'oh!)
I have two midiizers and have confirmed the sync noise is the same on both, even not plugged into power. Thats why i suspect the cables, or possibly an inner connection on the tape machines. I've been trying to hunt down the culprit of this sync sound for a couple years now..tried ground lift, new ground poles, but i think its only in the audio channels, or everything being hooked up with midi interface and multiple synths wired to patch bay..
 
Hi to all, a long shot but am in desperate need of the Midizer MTS 1000 manual. If anyone can help would really appreciate it.
Thank you guys.
John
 
I'm having an issue with a recently purchased Midiizer. The (+) function doesn't work. I replaced the key switch and all of the connections seem fine. The cue/locate seems to have a mind of its own. It will FF or RWD for under a minute in either direction regardless of my cues. Could this be a problem with the EPROMs? Anybody have schematics?
 
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