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Okay, what if the power supply is switching? This is bad right? What can I do to make it a non-switching power supply (what to look for inside)?

No, I have 3 PSUs that have 5v,+12v,-12v. I will certainly check with the voltmeter to make sure there's nothing going on. Thanks for the help with the PSU, I looks like it might very well work. I got me YMF cards today, mostly really worried about heating them too much when desoldering!

Whoa! Fix that

Sorry, what I meant was, if I wanted to make my own PSU, are there -12v transformers (or I guess -14->-15v)?

Okay, I do understand what you mean, but let's say I just bought 3 -12 Voltage REgulators from mouser. What Voltage should I be putting throught this to make it give off the least heat? I guess 1 V or something unless I can find a different negative voltage PSU right?

Well in terms of regulation I don't know, haven't opened it yet. But considering no one's really explained the -12v concept I see no other alternative source for such a voltage (it's not just a ground for the +12 is it?). Is it actually possible to make a midislave that is slaved to another FM? If there are any articles please let me know. I was going to have 2 in the same case with the same PSU.

Really? It can consume more than 1A. It seemed to me that the 5 wouldn't be a problem! So is it enough for 2 cores and 2 FMs?

I just found some old PSUs that provide the following: 5v 1.0A +12v .2 A -12v .2A Is that enough current for a Midibox FM? How much 12V and -12v current does it need to function? Would I be able to power 2 FMs off this? Also, can the different between 12 and -12 vdc be explained briefly? I'm kind of puzzled as to how that might work, or how I could think to supple -12v.

Sorry, but how much is a lot? 50? looks like I should go with Futurtec is it's so much cheaper there. Mouser isn't great per unit.

On the same topic, can anyone recommend how many 10 pin DIL, 16 pin DIL and the other sil connectors one would need? I havent found any info on this but hope it's been figured before (like "I bought X of Y and boy it wasn't enough of them").

571-1658620-1 is a part number for 10 position DIL connector It's really easy BTW, you just place the cable in and crimp down the connector. The SIL and DIL assemblies are the same, it's no solder, just contact.

Check out Smash's site. It's called "Female DIL IDC Connector" there. I too was looking for that but realized that's where I saw them. I might be placing a Smash order but if I find a mouser part I'll post it. http://www.avishowtech.com/mbhp/buy.html

Ahh, okay, so it's linked to the forum passwords! Because there was notwhere to sign up! I'll see what I can do, it's an Excel spreadsheet not a MS word, hopefully it will turn that into a table? Now I see why Thorsten didn't think anyone would want to do a 64 button matrix! I had always thought that the PCB mountable buttons would be dirt cheap. Datasheet or standardized LCDs? Okay, ebay it is!

1) Okay, firstly does anyone want me to email them my parts list from Mouser with quotes. I've got all the right parts and decent prices and you don't have to buy 5000 of anything. I was going to post to the Wiki but there's no sign up option, and I don't think it's very easy to update it anyhow. 2) Where does everyone get cheap momentary push-buttons? All I've seen on Mouser are around a dollar. I just want a bunch of cheap PCB mountable push-buttons but they don't seem very apparent. 3) Where is the best place for a 2x40 LCD screen? Mouser again fails at this respect. they have some for 20$ but there's no information on compatibility. 4) Where should I buy vectorboard? Mouser sells 16x 4.5 sheets for 15$ American. This is pretty pricey in my eyes and I think that some basic pad-per-hole or straight matrix board would be cheaper.

That's very useful, however, I still haven't been directly told whether the Duo-LED interface negates any DIN or DOUT modules or not! Sorry, I am preparing a large Mouser order and need to know!

So what you're saying is that I need a base SEQ with 2 DIN and 6 DOUT, and I then need to add 3 MORE DIN and 6 MORE DOUT. Meaning a total of 5 DIN and 12 DOUT? Because I was trying to make certain that the 3DIN nd 6DOUT on the vector boards counted as the DIN and DOUT boards or were extra. Sorry to ask again but it seems like a lot! Oh wait, I think I'm confusing the individual chips with the 4-chip board. So I guess they're adding less than I thought.

I think I'm getting close to figuring it out, as long as TK answers my last few questions and this one: Can you use electrolytic caps (one directional) caps for the 10uf caps for the 595s?

BTW Ultra you may have a few problems with the RGB leds because Thorston noted that using high-powered LEDs is tricky, and most of the RGBs I saw from the search were 5000 or 8000mcd. But I have no idea really.

Okay, thanks TK, very helpful, but TWO more questions. Would 15 uf ceramic caps be good enough for the use? I'm assuming the wiring to these chips are exactly like DINs and DOUTs (except for the missing resistors and the cathode matrix). So, to make a SEQ, would I need any more modules than a CORE, the panel (with the 2 DIN and 6 DOUT chips) and all its wiring? Because I'm not sure whether I'll need another DIN/OUT for the encoders or not. Aside from that I think everything is more or less clear.

Okay, seriously I thought that I was asking some pretty informed questions. If they're too dumb than I apologize, but I've really gone through all the SEQ posts (even tried linking to some to show that). Is the DUO-LED setup just onboard DINs and DOUTs? In saying that then why does there not seem to be any capacitors in either the DIN or DOUT chip? Is there just resistors for the DOUT in this (as there is usually resistors for DIN)? Because it looks like the 10k DIN resistors aren't included. I'm really having trouble as the resistors appear to have been taken for granted (and also modified).

Follow my second link, whomever did that panel indeed used 3-leggers and they look fairly even. I'm kind of far back in terms of the planning, I want a dense panel that somehow fits everything together pretty tightly. Mostly because I am anticipating a panel in the future with 32 steps (who knows)! I was thinking of making silicon buttons out of a small ice-cube tray but then the panel would have to be fairly large, and I'm not sure how sensitive my broad buttons would be. If I made silicon buttons I guess I'd just have to put the LEDs side-ways somehow so they're lower than the button itself. LEDs are a real mystery to me, dual colors seem expensive and the selection is really huge. I guess if I go silicon I could get two post LEDs? I here you just have to reverse the current and the other color lights? Anyhow I'll go with whatever is cheaper; I can't go really extravagant. I'm trying to figure out the cheapest or easiest knobs and LEDs and buttons and I'll be pretty much set to order from Mouser. Where'd you get those parts for your SEQ? Rack mountable is cute I guess. mine will be rack mountable, but only because I have a good supply of rack-mountable cases from my work (aluminum). My seq panel will be on the side however so it's not really going to ever be mounted on a rack. I do however have a perfectly rack-mountable network drive, made from xboxes. I work in telecom and ... 5Us is a lot!

Okay, I've looked through everything so here's my question. 1) Where are the resistors in this picture and how many do I need. I have no idea where they connect as they aren't in the diagram in the standard "/\/\/\" form. http://www.ucapps.de/mbhp/button_duoled_matrix.pdf The text in the pdf implies there's 8 or so resistors (the cathodes number at 8) but in the picture below there appears to be no less than 50. http://www.midibox.org/midibox_seq_blm_ext/ 2) Also how does this affect the other components. It says you need 2 DIN and 6 DOUT registers, i appears as if they are put directly on the board in the above photograph, so... do you still need other DIN and DOUT for the SEQ v3 or will that many (2 and 6) be enough for the entire module (and then all you need is the CORE)?? 3) Has someone improved the circuit as Thorsten has suggested? 4) What is the limit of the LED power before I have to change the resistors? Does anything that says "superbright" mean I should lower the resistance? 5) Will the following parts list (plus CORE and LCDs etc) be enough to make a DuoLED module? [tt]74HC595 6 511-M74HC595 74HC165 2 511-M74HC165 IC-Sockets for ICs 8 571-3902614 Dual LEDs 64 Momentary Push-Buttons 64 Diode 1N4148 " 64 78-1N4148 Resistor 220 Ohm " 32 291-220K-RC Resistor 150 Ohm " 32 291-150K-RC[/tt]

Okay, I think I have good orderlist for this module. Is the following enough to make one? (bare bones). [tt] 74HC595 6 511-M74HC595 74HC165 2 511-M74HC165 IC-Sockets for ICs 8 571-3902614 Dual LEDs 64 Momentary Push-Buttons 64 Diode 1N4148 " 64 78-1N4148 Resistor 220 Ohm " 8 291-220K-RC Resistor 150 Ohm " 8 291-150K-RC [/tt]

Has anyone improved this design yet or have any tips?

PS I am prepared to build a SEQ with: 1 DOUTX4 3 DINX4 1 MBHP_CORE 44 buttons 17 encoders 33 LEDs So I guess I'd need at least 2 more DOUTs for the increase in LEDs? Would I also need two more DINs?