Davo

If you haven't heard yet, Bob Moog died on August 21, 2005 after a brief battle with a brain tumor. http://www.caringbridge.com/cb/inputSiteName.do?method=search&siteName=bobmoog

That's the cleanest interior I've ever seen. :D

Let us know about the ironing process, ok? I have terrible results there, so I'm planning to get that toner-applicator/laminator discussed on the Pulsar page.

I buy mine at Radio Shack. It's one of the few things worth getting there anymore.

Well, now you know. (And knowing is half the battle!) TRF means "Toner Reactive Film". It's a thin sheet of mylar with a pigment on one side. You lay it over a toner image, iron over it and it sticks only to the toner. The green flavor seals and toughens toner for etching circuit boards. White is for putting silkscreen legends on the parts side of a board. The other varieties (metallic, white-type-Y, grey, and clear) are for making decals. If you want lots of colors, just use a color laser printer.

Direct toner transfer on Lexan is probably a bad idea. Go to http://www.pulsar.gs/ and read about how to use their stuff to make decals. That way, you can apply artwork to just about anything. If you're tranferring toner directly to the aluminum without doing the decal stuff, you probably won't need an overcoat as long as you apply TRF on top. I did find paints at the automotive store that are supposed to be baked on. Those are for stuff like painting engine blocks, brake caliper housings, barbecues, etc. I don't know if they're good for aluminum. I didn't check. Also on the primers, make sure the label says that it's good for aluminum. A label that says the paint will adhere to "metal" is not good enough.

For painting aluminum, you NEED the correct primer or your paint will slough off in sheets. Decent automotive shops will have spray cans of "self-etching primer". I got Dupli-Color brand and it worked great. Get some wet-dry sandpaper while you're there. Before you prime, sand the metal with 400-grit to provide more surface area for the primer to bond to. Wash the metal with soap and water. Make sure it's fully rinsed and dried. Shake up the primer and put a very light mist on the metal. It should look like a tiny bit of overspray. That's good. Wait for that to dry (say, five minutes), then do it five or six more times or until you have a uniform olive drab. After an hour or so after the last coat of primer, you can apply your top paint. I used ordinary flat black Rustoleum. Again, do the ultra-light misting with that paint. After every coat is just dry to the touch go over VERY VERY lightly with 1000-grit sandpaper and wipe with a damp cloth. Let the moisture from the cloth dry before applying the next coat. Five to eight coats seems to be good. I made the mistake of applying a thick coat of black over the primer and wound up with a rough and gooey surface that took two weeks to fully harden. I did that to a chassis, so it wasn't entirely a bad thing. I would have preferred a wrinkly finish, but oh well. BTW, you might be able to find spray paint at the automotive shop specifically designed to give a wrinkly finish. I only found it in red and I didn't buy it. Now about using toner transfer with panels, I haven't yet tried applying toner directly to a painted surface. I'm right now tinkering with .032" aluminum. Incidentally, this is the same thickness as circuit board recommended for use with Pulsar's toner tranfer paper and applicator machine. Their machine is a specific model of laminator known to work for this sort of thing. The greater mass of metal going through the applicator may cause problems. With your 1/8" stock, you'd be much better off using toner transfer paper to make decals.

I was hoping for a new line of non-modulars (like the Rogue, multimoog, etc). I don't think he'd have much of a change breaking back into the modular business.

This is a contradiction in terms. A digital sequencer is defined as a device that records and plays back MIDI events. If a MIDIbox SEQ has the ability to make its own sounds, then it becomes a sequencer with a synthesizer.

Whether or not to grind the tip depends on the type. Copper (with or without nickel plating) are supposed to be ground. Ironclad ones should never be ground. I grind my tips by hand with a single-cut file. What do you press your tips against when grinding them in a drill?

I'm working on a design for a quad SID midibox. Right now it's still in the design phase, but it'll have everything you need for a full control surface quad sid synth on one board. I've added a simple mixer to provide a mono output. When the board is finished and tested, I'll release foil patterns. A note of caution: I don't reccomend making a board from my patterns using an iron and transfer paper unless you know what you're doing. I had a horrible time getting even a halfway decent transfer with an iron. I'll be using a hot-roller laminator to do my tranfers from now on. .032" board is also a good thing to try. It cuts a lot easier than regular .062" board and can be run through an unmodified laminator.

From the referenced page: I read this as you saying that the 1MHz output is there because you had room for it in the core MIOS code and that it might be removed in the future to make room for something else.

CV means "continuous voltage". That is, a constantly varying voltage is used to control various parameters of a synthesizer such as oscillators, filters, and envelope generators. Poke around http://www.synthesizers.com and you'll find some more in-depth descriptions and examples. The AOUT and AIN modules allow a Midibox device to control and be controlled by CV signals. A big reason why the AOUT module exists is because running the output of an MBSID through a Moog-style ladder filter results in VERY VERY nice noises. Think of these sounds: "Ooooo... Wahhhhh... Ohhhhhh... Eeeee...". You'll hear something like that when "opening up" a ladder filter while a sound is going through it. Now, you can control how "open" a filter is with a knob, but it's easier to set things up so it opens and closes the same way for every note. That's what the CV input to a filter is for. The shape of the graph of the CV going to the filter determines if you'll get something that sounds like "BOWDUNG", "VOOP", or something else.

Something like that sounds easy to make in a decently-equipped metal shop. A standard box-and-pan brake seems appropriate.

I've never owned and only very rarely played with a Megadrive/Genesis. What is the sound of YM2612 like?

I'm seeing if I can come up with an all-in-one board for implementing a quad midibox SID. My design software (geda) is throwing fits over oscillator module footprints, so I thought I'd try implementing a 1MHz oscillator using just a crystal and support parts. I remember seeing somewhere a schematic that uses a crystal, a couple resistors, a couple capacitors, and a transistor to get a 1:1 pulse train. Can someone show me something like this?

While sequencer tricks can mimic "super poly", I'd very much like it implemented because it'll be very nice for live performances. BTW, Modularman, have you completed that six-way VCF design yet? Is it a real ladder filter?

GreenTRF isn't paper, but a pigment powder of some sort on a thin plastic carrier. I'm looking at the docs for the transfer paper and it says that the varieties of TRF are green, white, metallic (several colors) and clear. The clear TRF is for making soak-off and dry-rub decals. That's probably most appropriate for doing front panels. With a color laser printer, the results should be very nice. I'm now sure how to get white on such a decal though. You could probably lay down your backgrounds directly as if you're going to etch the front panel, then apply WhiteTRF. Then put a decal using ClearTRF over that. See http://www.pulsar.gs/ for more info. I don't see why green or white TRFs can't be used with the Gootee method. They adhere to toner fused to metal, which is exactly what Gootee's method results in. For soak-off and dry-rub decals, you need the special gluey coating that Pulsar puts on their transfer paper. That glue is washed off when using it to make circuit boards.

Yes, it's a laser. My first try with this paper was on a Laserjet 4050. I got much nicer results with the Xerox, however that may have been just because it was a second attempt.

I'm aware of the Gootee site and I've been trying what I see there. The stuff I'm using are TTS paper and GreenTRF from Pulsar. TTS is designed specifically for this application, but is quite expensive at $1 or so per sheet. I bought it shortly before I found Gootee's site. The printer I'm using is a high end Xerox Phaser of some sort used for graphic arts at the local university. I'm considering using the stuff Gootee uses to see if that works any better. There are not Staples places where I live, so I'll try one of the listed substitutes. GreenTRF is a sealer that's ironed over the toner to give a very tough mask. There are other TRF types such as white for doing "silk screening" for the parts side of a PCB. There are others for other purposes. Now for a critique of this TRF stuff. If you look at my foil patterns, there are some very wide areas. It might have been my technique, but there were pinholes in the green stuff on those wide areas. For the narrower parts, where I managed to get nice and sharp edges with toner here and there, the green was nice and sharp. It covered all the unavoidable unevenness and pinholes in the toner and looks a lot like real silk-screening. Applying full pressure from my fingernails, I cannot scratch it either by tapping or scraping. It's somewhat, but not really resiliant against getting banged with 1/4" plugs and MIDI cable ground shells. Since the green stuff was meant to be removed with acetone, that may or may not be a concern for using it on front panels. It might complicate spraying laquer over it too. I don't have any other TRF types, so I can't comment there.

Can I get some advice from someone who clearly understands how to use toner-transfer paper? Some time ago I posted something about making a simple mixer to mix the four outputs from a Midibox FM or a quad SID to a mono output. I entered the schematics into Geda (href="http://www.geda.seul.org) and routed the PCB traces using PCB (same page). I exported the foil patterns to Postscript format and with LaTeX made a full sheet containing some foil patterns I want to print out on the toner-transfer paper. The resulting PDF can be found here http://www.cs.csubak.edu/~dgriffi/stage1.pdf. The mixer is the smaller pattern printed three times on the lower half of the page. The top half contains two copies of a two-sided board pattern for some mods I plan to apply to my Paia Fatman. Would someone please take a look and tell me if there's anything wrong with the artwork. How hard should I press? How long? How hot? With or without a sheet on top? After blowing one sheet, I found that rubbing instead of simply pressing helps get things bonded, but I still keep getting lots of broken traces. I'm about to sell this stuff off and go back to the photographic process.

I was under the impression that CEM chips weren't made anymore. Am I wrong or are these new-old stock pieces?

PICTURES!!!

I see those synths on Ebay all the time. What are they like?

I'm in the middle of a multiple-stage hypermodification of my Paia Fatman. The first stage includes stuff that requires only one toggle switch, one pot, or less. Those will be mounted where the front-mounted jacks used to go. Two of these is a VCF expansion that gives a more moogy 24dB/oct and a VCF input jack. If I can figure out how to implement a simple gate and pitch output on the SID and FM synths, that would take care of my desire for a VCF for a while. According to the schematics, it looks like I can simply plug those CVs into the appropriate jacks on the Fatman. More about the modifications, it seems like the Paia Fracrack is an ideal platform to mount further mods. It might even be nice for assorted knicknacks connected to midibox-based synths.