Davo

BTW, that was "Borne Identity". "Johnny Mnemonic" was about data smuggling and the Yakuza. Davo

According to ucapps.de and SmashTV's site, some 2.7 nanofarad (2700 picofarad) capacitors are called for. However, it looks like SmashTV is linking to a Mouser page for 2.7 picofarad caps. Which is the correct value?

For those who didn't know already, you can use toner transfer paper (the wet kind) to make decals.

So this is back to the earlier discussion of resistor ladders controlled by a DOUT module?

Sorry if this has been asked before, but what's so special about the max525 chip? I perused Jameco and found the following DACs that I think might be suitable to build a lower-cost AOUT. Would someone who knows better please check this out? DAC1222LCN (#14980) 12-bit $9.95 7109CPL (#43764) 12-bit $7.49 TLC5615CP (#239425) 10-bit $3.49 IMHO, this lower-cost AOUT module ought to be able to support more than just two 16-bit outputs at once. Or at least have an extended version of the 2-output one.

FWIW, 62256 SRAMs are fairly easy to find on Ebay. A few months ago I bought around 60 of them for an unrelated homebrew project. They're almost always pulls, but they work well and the price is good.

A big problem with that thing on Ebay is that DD 3.5" disks are rather difficult to find now and the device most likely uses a weird format that isn't readable anywhere besides that device. The MBSEQ has code that looks like it could be tweaked to do what I'm talking about. Data could be dumped to and from a bankstick. Davo

It occured to me that the midibox core should be able to handle capturing keyboard setup dumps (ie, from a Roland AX-7). I guess the MBSEQ provides something like this, but I'm not sure. Davo

It might still be salvagable for a more experienced solderer. For me, I'd solder some bare buswire to the broken stubs (even if they're flush, this should work). Plug the chip into a high-quality machined-contact socket, then solder the buswire pins to their respective holes. Add a little epoxy to make sure it never comes out and you're good as new (sort of).

There's a shop in the town I live in that has a bin full of old soundcards. That's the route I took. To get the chips off the board, I laid copper braid over the joints, pressed a hot iron over it, and wicked up the solder. Then using a fresh exacto knife, I gently lifted the pins one by one. It's not terribly difficult to desolder these chips. A solder-sucker is overkill.

It's not a socket, but Ares makes a thing with SMT solder pads and DIP pins. Check the handy Mouser catalog.

That stand-alone board, is that for a ladder filter intended to be combined with a sid synth? If so, I'd like to have the layout. Can you put it in Postscript or PDF? I'm not sure how I'd be controlling the filter modulation. For now, I think I'll keep the Fatman in a stock configuration and see what that standalone board can do for me.

I'm not sure exactly which mod will provide this, but I'd like to use the Fatman's VCF to create a more moogy sound. I forget who posted an mp3 of that.

I'm putting together a Paia Fatman (http://www.paia.com/fatman.htm). Does anyone else here have one and have you tried combining it with a Midibox SID. I'm especially interested in adding the filter-in mod.

WARNING: This is a mental model I've been playing with for a couple weeks. More experimentation is necessary. Suppose we have eight resistors connected in series. This arrangement adds up to 10k ohms or whatever. Alongside each resistor is a bypass controlled by a transistor or triac. The bases of these eight transistors are connected to eight DOUT outputs. The 256 discrete resistance levels should be acceptable. The front panel of this hypothetical synth will be composed of lots of digital encoders, each with a display composed of three 7-segment LEDs. An LCD display will show the current patch name and slot number. The idea is you can see the entire state of the synth at once. Load up a new patch and all the LEDs above the encoders change to reflect the new settings. Someone, please check this out and tell me if I'm right, wrong, or insane.

Can we retire this thread? I recently found that PAIA has rackmount chassis for very good prices and appear very suitable for homebrew synth.

I'll email you when I get home (a few hours). Yes, it has a backlight. BTW, it's "Davo", not "Devo", though I do like that band. A coworker gave me that name a few years ago because my name is Dave and that I came to work once wearing a yellow tyvek jumpsuit.

Somehow I wound up with an extra 20x2 LCD display. It's the same one offered by the Ebayer "kbaoj". If anyone wants it, I'll sell it for $7 plus shipping. If it makes you feel better, I'll put it up as a private "buy it now" auction for you.

How about sharing that .fpd file?

Dual concentric knobs look nice for squishing a midibox synth into a lower-profile case. Now how about encoders that can take advantage of that sort of thing?

What do you guys do for rackmount boxes? I can't seem to find any used ones and I'm not sure if putting a metal faceplate on a homemade wooden chassis is a good idea. In the meantime, I'm considering buying a couple plastic rackmount boxes from Mouser (part numbers 563-PRM-14462 and 563-PRM-14464, page 1183 in catalog 620). What do you think?

My initial impression of sending raw data between pics is "bad idea". I don't know how long is the maximum allowable cable is, but when you're talking about wiring boards together, it isn't much. Now for cobbling together a wireless MIDI system, that's probably even tougher. I'll think about what would be required and post back on it in a week or so. Perhaps an easier approach would be to use modified telephone handset swivels. I haven't considered how much noise that would introduce to the signal, but it's somewhere to start.

Has anyone here used lighted buttons for the selection matrix on the midibox SID full control surface? Can anyone tell me what sort of programming changes are necessary to support this?

I'm interested in building a MidiBox SID with an internal power supply so I can avoid the annoyance of wall warts What do you guys think of the open-frame switching power supplies on page 138 of the Jameco catalog (#251, Feb 2005)? Would an enclosed PS be a better choice for keeping hum out of the SID modules? What wattage is ideal? I've seen some designs here that use a simple transformer and not much else, depending on the bridge rectifiers on the modules to get DC. To me, this seems like asking for hum troubles.

So perhaps ganging two core modules together might provide the necessary resource?