NorthernLightX

I believe any LED needs a resistor before connecting it to current. Look at the DOUT board, all those resistors are there for the LEDs they supply. Cheers, Alex.

OK, not really an answer I completely understand, but I gave it a shot and connected the branches just behind the 100nF caps, works fine! The only problem now is that since I rebuilt the PSU board, the 9v I measured erlier now measures 8v. Right before the 7809 I still measure 10,5v, so this has not changed since the rebuild. Has the 7809 been too hot perhaps, bacause of soldering and desoldering, or do I need to seek the cause in a different direction? Cheers, Alex. [edit] I'm going to post this question in the troubleshooting forum, as it isn't a design question. [/edit]

Don't take the language so hard Drin, it might very well be a translation done by a non native English speaker. If I would for example look at it as a crude translation out of Dutch, the "may" in fact makes it a more polite question. (the "want" earlier in the post on the other hand is as rude in Dutch as it is in English ;) ). I agree, topic starter should go first, but I'll take a shot anyway: I don't have a lot of experience with parts, but the ALPS rotary encoders I bought have a solid feel. Absolute shitty parts: The rotary encoders on my Yamaha A3000, man do they suck!

Bedankt voor de massale reacties ( ;) ) maar het is niet meer nodig. Ik heb even mijn best gedaan en het redelijk netjes opnieuw opgebouwd op een nieuw stukje eilandjesbord. Alleen over de ground ben ik er nog niet helemaal uit, zodra dat bekend is (zie vraag in het Design forum) kan ik testen en volgen er plaatjes. Gr, Alex.

I tried to read the article, but I don't understand most of it. Why does he need so much PICs? Does this toy need that much processing power?

Hi moebius, where would be the best place to connect the 5v ground to the 9v ground? At the end of the branches, or earlier, like before the regulators? thanks, Alex.

Great! Thanks Moebius! I still don't understand how the common ground could affect my 5v, my 7805 regulates that, doesn't it? With all my gathered knowledge here I can (and will probably) write a newbe howto on PSUs someday :) Might even become part of the fotoblog I'm planning. Cheers, Alex.

Hi, I'm using this schematic for my PSU: a short question: - Is it wise to connect the ground lines of the 5v and 9v branches, to create a common ground? If not then please also answer the following question: - I'm going to wire up 4 Core boards and 4 SID boards. On the SID both 2 voltages are used. Should I use the ground from the 9v branch, or the 5v branch? And another one: The MIDI and audio jacks, where should I ground them to? Is star-topology grounding an issue here? Thanks in advance! More pics of my PSU design will follow shortly ;)

That's her allright :-) But no, seriously, I don't know jack pooh about modular synths, so it's all Chinese to me anyway. (Quad quardant range oscillator? Yeah, with ice and a straw please! ::) )

I hope you didn't understand me wrong: I didn't ask to see who gave the points, I asked to be able to see which post the smiting/applauding person was looking at when pushing the button.

What I still would like to know: is there a way to see for which post you received your own karma points?

There is this one chick named Cynthia or something, she digs synths and DIY stuff.....but I read somewhere she used to be a man... ;D

Hi all, I sort of know a guy who used to be in Witan (a dutch demogroup), in which also Jeroen Tel was a member, and he claims still to have friendly contact with him on a regular basis. I beleive most of us know Jeroen Tel by name and fame now don't we? ;D I could ask via this guy, if Jeroen has some sounds he would like to contribute. Only I don't think he owns a midibox, he used to prog te sounds via C64 based trackers and so if I recall correctly. Apart from donating/lending him a midibox, what are the options to get MBSID compatible patches? I believe i read somewhere he does own a HardSID tough... Cheers, Alex.

Hallotje, ik wil graag een PCBtje etsen voor mijn MidiBox voeding. Iemand de spullen in huis om zoiets te ondernemen? (Er mag uiteraard wat tegenover staan ;) ) Gr, Alex.

Hi all, I've completed my PSU! ;D Voltages delivered are 5,06 Vdc and 8,93 Vdc. I'm sure the 5V line is OK, is 8,93 V enough for the SID line (8580's ofcourse)? Some pics: http://home.quicknet.nl/qn/prive/alex.span/midibox/psuboardtop.jpg (looks pretty 8) ) http://home.quicknet.nl/qn/prive/alex.span/midibox/psuboardbottom.jpg (looks awful :P ) Final schematic: http://home.quicknet.nl/qn/prive/alex.span/midibox/psufinal.png Hope to etch a PCB for this one. By the way, there re a few (6 or so) of these trafo's left at the store I bought mine, they are pretty easily modify-able to supply 8,6Vac (standard) and about 5,8Vac (modified), and they cost about 3 euro's. If anyone's interested drop me a message, and I'll see wht I can do for you. Cheers, Alex.

As far as I know (and I haven't built this box) is that every card listed on the OPL3 module page on uCApps carries both chips (one YMF262 and one YAC512). Now for 4 channels instead of two you'll need a second YAC512. Basically you'll need another card carrying both chips, and only take the YAC512 from it. You can probably trade/sell the remaining YMF262 on the fleamarket forum over here, or hold on to it as spare in case you fry your own. Cheers, Alex.

You'd be sorry to know then, that i will have the case made from aluminium as soon as I'm done fitting everything in. :-[ The the case will be reused for another project though, I promise ;) (If I hadn't made the mistake of miscalculating that one inner measure, so it would really be 5U, I might have kept it for the finished product, but alas). Really, I can hardly find the time to finish the MidiBox (have been busy for over 3 years now), another study won't help with that ;D No, I can do without the autocad file, but if someone wants to reproduce this case and does make a file for himself (or herself), I'd be happy to receive a copy. I already have this stuff (Loetlack from reichelt), but it doesn't restore the original copper now does it? Oh well, those SID boards are pretty useless for me anyway (those are 6581 boards and I only have 1 6581, and a bunch of 8580's). Also there've been some mod's to the layout of the boards, so I might even cannibalize some parts I need from them and then try to sell the boards (If that's allowed anyway) to someone willing to make the mods and complete them. I want my box to look pretty at the inside too, so I'm going to order the new boards from SmashTV. I might hold on to the cores for use in (an) other project(s) perhaps, and one SID board for the 6581 (to make a small 6581 midibox). If I find the time to do so :) Thanks tel3, the wood will probably get solder stains on it yeah ;D No really, I'm not planning on making the wood prettier, It's not all that pretty wood in the first place, and when drilling it the wood splinters around the holes. So it won't become more than a Test case I suppose. Maybe I'll sell it too as soon as I'm done designing the frontpanel, so someone else can have fun with it. Cheers, Alex.

Hi all, latest pics: http://home.quicknet.nl/qn/prive/alex.span/midibox/case3.jpg http://home.quicknet.nl/qn/prive/alex.span/midibox/blueprint.jpg <- this is the building plan. Sorry for the not so clear numbers, if you have any questions feel free to ask. I don't have autocad or anything on my PC, if someone does and would be willing to make a file from this case that would be very much appreciated! @moebius: sorry, have to rearrange my rack config to fit the 5U in, will post a pic as soon as I have the time to do so. P.S. The boards shown are not finished at all, and probably won't ever be, as there's severe oxidation on the copper leads. They're just in the pic to show how nice they fit in (and I never even took measurements for them, having some luck for a change ;D )

Hi Davo, you are right, this case is not to stick rackmount things in, it's rackmountable itself (as long as the frontpanel is attached). The plywood used is in fact 5,5mm. The bottom dimensions are perfect for MidiBox, a Core+SID combo fits exactly. For the mounting I will probably walk the exact same way I would if it would be an aluminum case, that involves drilling small holes in the bottom, and using long, thin bolts and spacers to mount everything. Right now I'm still working on the PSU, next pics will be: the case rackmounted, the back with all the parts stuffed (8x jack, 3x MIDI, powerplug, powerswitch, fuse, powerLED), and the internals with the PSU mounted. I'll try to scan the buildingplan today, and post it. Cheers, Alex.

Hi, some small questions: If I'm going to replace the 2200uF caps by bigger ones, should I also change the 330nF caps for bigger ones? If I'm going to use the schottky diodes, where in the chain is the best place to put them? Right at the end, just before the power goes to the boards? Thanks in advance, Alex.

Als het aan mij ligt binnen 2 weken, maar SmashTV heeft ook nog geen definitieve shipping date voor de nieuwe bordjes, mind you. Dus ik bestel pas als de nieuwe double layer designs uit zijn... en ik bestel waarschijnlijk gelijk kits. Krijg ik er wel allemaal rommel bij die ik niet ga gebruiken (gelijkrichters, caps etc. voor de stroomvoorziening, die ik anders ga doen) maar die vinden vast wel ergens een nieuw thuis. Wilde jij inclusief onderdelen bestellen? Anders kun je wel het een en ander van mij krijgen, ruilen tegen een paar biertjes of iets anders electronisch ofzo...

Hi All, Will post pics of the building plan and the unit in a rack soon, maybe tonight, right now I'm a little busy. Small comment: because I had to calculate the inner measures on the fly in the store (didn't know the thickness of the material upfront, and let them saw most of the pieces, saves me work and they have equipment that roxx) I made a small error on the smallest side, so this unit in theary does not fit tightly in a rack, as it is a few mm more than 5U. Oh well, it's a temporary case anyay, so i don't care.

Ik kan me nog een synthforum.nl meeting herinneren van een paar jaar terug die ook erg geslaagd was (sorry Twin, het was je kindje, ik weet.) Encoders heb ik al. ALPS, via Nat van het forum. Kapjes heb ik ook, Waldorf (zelfde als Thorsten heeft, komen uit dezelfde order) via Joerg van het forum ;) (beide jaaaren terug alweer). Joystick zit niet in mijn MidiBox design, mogelijk later met iets, maar nu even niet. Ik zoek mogelijk nog wel aparte drukknopjes, daarover ben ik met pay_c in discussie in het Midibox of the Week forum, voor een aangepaste versie van de modulatie matrix. Plus dat ik alle bordjes opnieuw ga solderen, dat spul van mike is leuk hoor, totdat je de bordjes van SmashTV hebt gezien :-\ Dan om de vraag van Twin-X te beantwoorden: ik ga een Midibox SID met volledige control surface, 4x 8580 en een interne voeding maken (ja, dat duurt nu al een jaar of 3 ja :) ). Als die goed werkt wil ik nog een Midibox filterbank maken, en een eDrum module om met mijn A3000 sampler te gebruiken. Of om met SID geluiden te drummen, w00t! ;D

So, why can't we connect X and Y, instead of both with ground? Is that software related? Still, I don't see (n00b as I am) what the difference would be between shorting X1 with ground and Y1 with ground at the same time, by pressing either one or two buttons... please explain it to me, I must look so ignorant :-[

Hi! Just wanted to show off my selfmade enclosure ;) The material is wood, I don't know the English name but in Holland it's called triplex (means 3 layers of wood) For the time being this is a temporary enclosure, the costs were about a tenner (in euro's) If the electronics, especially the frontplate, are finished, I will probably have it remade in aluminium. Links to the pics: http://home.quicknet.nl/qn/prive/alex.span/midibox/case1.jpg http://home.quicknet.nl/qn/prive/alex.span/midibox/case2.jpg Watch out: pics are uncropped, and about 750kb a piece. If requested I'm willing to scan the blueprints and post it here. Cheers, Alex.