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So wait, let's say I have a 5v power supply, how long would this 9+- volt supply (in conjunction with the 5v PSU) last? I recall Thorsten saying that they 12+- line draws very little current.

And of course thank you Kris!

Like a big 220 package? How many leads will it have? Three? Oh wait, I just found, marked on the board, a small IC with a PCB label of SCR. I hope I haven't destroyed anything. I'll have to now swp different replacement ICs around I guess. Thanks man. It really sucks because I was trying to get all the datasheets for the parts and that was the one I wasn't able to get a datasheet for. Of course who knows if I would have known what it meant had I found one anyway.

YEAH! Thanks Lall! Looks like it's totally working now! I can't thank you enough for burning the eeproms and mailing them over!

Some thoughts, so what you're saying is that, possibly, the 5v line has a crowbar circuit on it? Any that it might in fact be configured to spring if over 5v by a certain amount? Any that therefore hacking the output to 7-9v will make it not work at all? This would explain a few things, why I blew the fuse on one of the PSUs when only increasing a bit. Sketchy, so I suppose this is bad news as crowbars are dangerous to a psu's components if you happen to have bypassed the fuse ... ;-P

>Is this a mains powered switcher? If so be very careful - they have lethal voltages on the board, and can >stay charged long after switch off. Gotcha. >Major word of advice: make up a dummy test load before any other work - say a BIG 10 Ohm resistor, that >way you won't risk frying any of your PIC's or SID's if it all goes wrong. Some switchmodes won't work >without a load, by the way. Some have an over voltage crowbar circuit, design to short the output should >the voltage go too high, just check you haven't got one set below 9 volts. I of course do not have anything connected when I am doing this mods. But it has been sending out a steady voltage when nothing is connected in the past. I might scrape around for a large resistor though to make sure. Hmm, crowbar circuit? I'll look into it. >I have a lot of experience working with things like this, starting with television repairs as a student. Even >so, I think twice about working on one, and will only do so if there is no other option. I don't have any other PSU unfortunantly. I had the alternative of throwing a 9v wall wart into the mix but now that this thing isn't working, at all, I have no 12+- to speak of. >There are some very good guidlines here http://www.eio.com/repairfaq/sam/smpsfaq.htm Thanks a lot for the help, I'm going to get reading!

Does anyone know much about switching power supplies (I believe it's flyback style)? I think I might have broken mine somehow and am unsure what I should replace. Basically I had a switching PSU with 5v (switching) and linear 12+ and 12- I found the datasheet for the reference voltage IC and figured out that I should change the value of a resistor so that it will generate aprox. 9v DC (so then I can put it through a linear reg and everything would be great). However something went wrong in that area and now the unit produces no (.11v) voltage whatsoever, even when it's changed back to the original resistor value. Does anyone know what the most sensitive IC in this type of power supply is, or what I might try replacing? I have replacement parts so I can swap whatever transistor IC etc that I need. Or if anyone knows a good PSU forum that would be appreciated, I can't find any.

Okay, but these don't act as hard drives correct? How do I load the (3) preset files onto the eeprom without saving over the other ones? What is the Bankstick Syx file that comes with the FM?

Ooops, there's only a low-res version of the schematic, I didn't see different pins were high.

I read the whole bankstick page but am somewhat unsure. If I plugged 3 in series then it would format them all and configure them as 1,2,3 automatically?

Ah, so really only one I'm guessing. Unless the default pre-prepared stuff is over 100 already.

How does one determine how many banksticks to use? I made an FM and it might eventually work. I'm willing to put up to 8 in, but how many will I actually use? I guess as a starter how much space do the presets and stuff take up?

Okay, well I'll give it a few days. I guess there isn't much of a user base to plum for pointers. Was hoping someone could say "I had this problem, try this..."

I'm just so unlucky that I found a PSU that supplies 5v, 12+ and 12- instead of 7, 12+ and 12-. BTW I think the FM setup is sketchy. There are supposed to be 2 sockets, one for +12,-12 and GND and another with just 5v. So if you forget to connect it you can send 5v to an ungrounded module (burnout). I might have done that at one point, it's easy because it's not setup as a 4 conductor connector which would make that kind of mistake impossible (unlesss... I find a way)

Crap, so I guess no one has any pointers? I've tinkered around quite a bit with no results. So far I swapped out the entire FM module for another one + all the amps with nothing positive happening. If no one has any suggestions then I just mad a large brick.

Oh man, I totally did the same thing, I was trying to debug my FM and was getting kind of frantic as nothing was working. So I ended up swapping a hundred things, plugging in ground and -12V and turning it on. Thank god I didn't have my FM module attached, or any other module for that matter. So I basically just killed the PIC and the Octocoupler, not too much loss, as I was prepared for other projects and had extras.

I don't think it's too random. ;-) As I said I guess I fixed the core by reflashing, no more weird midi signals. Now I loaded the sine wave app and it's acting really spasmodically. I was able to load just one amp at a time, in the one socket (the one with a different orientation). Each individual amp actually worked. Then after checking all 3 in this manner (same place alone), they turn out fine. But if I plug 2 into the module, it will then not work anymore at all

Okay reflashed without any bankstick or presets (or even the bankstick plugged in). I actually says it's starting up Midibox FM, and appropriate (seemingly) lights ligt up on the console. But unfortunately the sound coming out of the FM is a horrible modem like thing. No more weird midi messages but there is always a creepy sounding hum ,and when I press the keyboard there's a really weird howl that emanates from the box. Anyhow had this as well? Also I can't control the HUID at all for some reason, everthing is wired but not a single button gives a response from the LCD or any LED

How easy is it to determine whether a PSU is switching or linear?

It says on the LCD "MIOS 1.9d" at least once, where sometimes it repeats it (goes blank and then says "MIOS..." again). Then usually it says some musical/midi value "blah 127". The MIDI in monitor gives loads of settings changes as well as an [ff] reset log. It appears as if (to me at least) the FM program is indeed loaded and is running to whatever extent.

I loaded the entire board with everything. There should not be any floating issues if we're talking about resistors on the board itself.

Arg, even with all control surfaces, and even the DOUT and DIN modules disconnected the FM is still acting really strangly. I loaded the main.hex and thorsten's set.hex (that's my control surface setup) and a bunch of the presets for the bankstick.

Okay a few problems, looks like my FM is a little schitzo, I get a lot of messages over midi after turning it on without actually touching anything. One particular problem seems to be a consistant system reset. Is there anything I should be looking at that might cause a system reset? Also there's nothing but static coming from the outs.

Maybe you can just figure out adaptors ? Little PCBs that convert the SMD to DIP

Oh, special thanks to Jidis for the MBHP Burner board that made this possible!