Muff's Modules & More

Jarno · Posted: Thu Mar 17, 2011 4:24 am Post subject:

I actually searched for 2n3638 and got pn3638, specs look the same, but you will need the "non -A" version because that one has a much higher Hfe.
Could only find the pn3638a on eBay, anybody got a source for these?

Peake · Posted: Thu Mar 17, 2011 2:50 pm Post subject:

J3RK · Posted: Thu Mar 17, 2011 3:43 pm Post subject:

By mylar for classic I meant it contributes to a slightly thicker? Sound. There are a lot of variables at work here, but it did seem to make a slightly audible difference. Polycarbonate should be listed as well, but I haven't personally tried them. I'll definitely get some to try out now though w00t

nice blog too! I'm planning a pair of accurate/modern ones, and a pair of vintaj/mostly vintage ones.

Rod Serling Fan Club · Posted: Thu Mar 17, 2011 3:56 pm Post subject:

Glad you are doing that Peak. I am still working out my approach but I am going to do 2 double oscillators and I think I might build one of the “258s” vintage per your info and maybe go for cleaner modern (or just different) approach with the other. I like variety.

Peake · Posted: Thu Mar 17, 2011 4:27 pm Post subject:

Interesting that, about the mylar. I'll try it too. RSFC, yes, variety is fun. I'm glad in this project that we get lots of choices.

J3RK · Posted: Thu Mar 17, 2011 6:00 pm Post subject:

I just used a Greeny-esque mylar on the old one. Now to find some other varieties. Mr. Green

sanders · Posted: Thu Mar 17, 2011 8:51 pm Post subject:

Where do u get these polycab caps?

How about the Mylar ones?

i think that my arp odyssey uses silver mica.

J3RK · Posted: Thu Mar 17, 2011 11:49 pm Post subject:

Mylar is available pretty much anywhere. They're quite common. They're usually glossy, roundish squarish shape a lot of times. Mouser has Silver Mica. They are fairly expensive. I wanted to try them in something I was working on, but for the amount I needed, it would have been very expensive.

gwaidan · Posted: Fri Mar 18, 2011 1:22 am Post subject:

Polycarbonate sorta disappeared in the early 00s, so all that's available is NOS-see http://my.execpc.com/~endlr/film.html for more details

brother303 · Posted: Sat Mar 19, 2011 4:14 pm Post subject:

Hi J3RK,

would it be possible to provide some wiring diagrams with the building instructions of how to wire up the tl074 (output boost) to one muck and the lin/exp-switch mod to another muck?

This would be incredibly helpful!

thumbs up

Best regards
Greg

J3RK · Posted: Sat Mar 19, 2011 4:55 pm Post subject:

I can do a little non-inverting amp diagram using a TL071 or TL074. I need to go back and read through the lin exp thing again before I could do that one. It sounds simple, I just need to re-read it.

brother303 · Posted: Sun Mar 20, 2011 6:25 am Post subject:

Hi,

emdot_ambient · Posted: Mon Mar 21, 2011 3:54 pm Post subject:

...and so, with 2 boards ordered, I finally have to dig into the "rare and expensive" parts sourcing game sad banana

I've been dreading this...

J3RK · Posted: Mon Mar 21, 2011 4:36 pm Post subject:

None of them are THAT rare, or expensive really. If you go for a real 4339, that would be where it might get a bit expensive. Otherwise I found that J201 for the sine shaper is cheap, nearly the same, and does an excellent job. Exponential converter is relatively cheap if you go with a THAT340. It's $6 but it also takes care of another pair of matched NPNs from the board as well. The 2N3638 is hard to find, but the NTE 129 replacement for it is available, though relatively expensive. Not horrible though. CA3080s are readily available in the $2-$5 range, and that's pretty much it for the tricky stuff. You can get all of this (short of a real 4339 and the CA3080) at Mouser.

emdot_ambient · Posted: Mon Mar 21, 2011 5:45 pm Post subject:

thermionicjunky · Posted: Mon Mar 21, 2011 5:48 pm Post subject:

J3RK · Posted: Mon Mar 21, 2011 7:25 pm Post subject:

That's the correct THAT chip. I forgot about the tempco. I would go to either Bridechamber or Magic Smoke for those. I'm sure there are plenty of other places, but I know they have these ones have them. Mouser may have them, but I haven't looked. I like the big PRC ones best.

emdot_ambient · Posted: Tue Mar 22, 2011 2:50 pm Post subject:

Cool, thanks! Sometimes me and Mouser's search function...well, let's just say it's a relationship we're both working on. lol

theantiroman · Posted: Tue Mar 22, 2011 3:13 pm Post subject:

Is anyone going to build the modern version only?

I'm going to look for a parts list for that, that is, try to assemble one.

I'm probably not too interested in tracking down crazy parts but I will be building up two boards and placing them in a single panel.

Also what is the rationale to go about running this on 12V, if it will run off that? Not really a problem if it won't; I need to learn my power supply DIY tech eventually anyway!

Luka · Posted: Tue Mar 22, 2011 3:26 pm Post subject:

i think ill use modern parts and wont bother with THAT IC