Telex: Teletype expanders

buma · 2020-07-14T19:40:54.174Z

Ah ok, I understand If you join the Pusherman group on Facebook, you might find someone there who will build it for you. Or perhaps directly here on Lines ?

a773 · 2020-07-16T14:47:19.923Z

Grrrrr. So today one of my txos stopped working. As expected wiggling the boards made it work perfectly again. However much I appreciate the txos (can’t live without them) the idea of using machine headers to shave off a few mm depth is… not that great. Ordered two pcb/panel sets from pusher man, will use regular headers like I did on the txi, which is rock steady.

I can’t stand the notion of these comming apart on the way to a gig and me having to wiggle pcbs during soundcheck.

Sorry, just had to get it out😏

xeric · 2020-07-16T15:13:37.349Z

Mine weren’t wiggling free very often, but just in case I used a twist tie around the boards to keep mine super secure. Haven’t a problem since

bpcmusic · 2020-07-16T15:58:19.338Z

Yeah - definitely regret not finding space to connect the boards together more firmly. I really tried, but most of the space on the boards was spent trying to simply navigate the pins from the Teensy to the front board. It is such a rats-nest maze. (If I ever get around to a v2 this is one of main things that will change. I imagine it will ultimately look more like the TXn/TXff.)

Zip ties are definitely a good answer - or a bit of string if you want something thinner. I’ve also experimented with 3D printed braces but ultimately abandoned the idea because it wasn’t as effective as the zip tie solution.

You can always just solder the boards together. Makes future repairs a nightmare but turns the thing into a tank.

XiXora · 2020-07-16T21:21:31.598Z

Ah! That’s a plan.
Mine fall apart by looking at them. I’ll solder them together when I get the chance.

Hopefully, some space for a spacer or something can be found one day.

toneburst · 2020-07-19T23:59:03.596Z

I found these square-pin, low-profiles female header sockets work well. They’re pretty tight, with standard square-pin pin headers.

IMG_76063024×4032 1.72 MB

They shave a few mm from the overall depth of the module, too. I’ll be using them again, if I ever make up another Radio Music!

a773 · 2020-07-20T05:29:27.197Z

Yeah they look much better, do you have a mouser number?

toneburst · 2020-07-20T08:40:15.915Z

Manufacturer’s part # is 929984-01-36-RK.

They’re quite expensive, but worth it if you need to reduce the depth of multi-board modules.

a773 · 2020-07-20T14:15:34.969Z

Thanks!!! +20 chrs

toneburst · 2020-07-21T10:44:36.960Z

Does anyone have any tips for low-profile II connectors?

I’m hoping to mount my Terminal + expanders in a Behringer 104HP case, which is pretty shallow.

a773 · 2020-07-21T10:47:29.102Z

I have teletype and txi with regular headers in a mantis (should be very similar to behringer) and there’s plenty space…

toneburst · 2020-07-21T10:59:31.406Z

I’ll give it a try with what I have, then.

Meanwhile, do I have to join the two boards with headers here?

IMG_76113024×4032 1.65 MB

a773 · 2020-07-21T12:17:28.835Z

It’s just for stability, IIRC

bpcmusic · 2020-07-21T16:04:33.732Z

It also provides some additional ground plane unification. (I’ve never tested with it disconnected.)

Those headers look amazing, btw. Have the P/N handy for the male side?

toneburst · 2020-07-21T16:43:29.685Z

I’ll add the extra 2-way header, then.

The male headers I used there are just bog-standard male 2.54mm square-pin pin-headers.

To get the correct length, I installed them upside-down, rather than trimming the long ends to fit into the low-profile socket.

I’m probably not going to use this approach next time, though, as this meant trimming the longer ends above the board, and it was hard to trim them neatly (especially on the top of the Teensy 3.6 board, where there wasn’t enough room between the header pins and the Teensy’s MCU to get my snips in to trim the pins down to the board).

The part number for the low-profile female header is in my post above.

toneburst · 2020-07-21T20:49:25.560Z

Blue’n’red LED TXo.

IMG_76123024×4032 2.44 MB

A couple of questions:

I don’t seem to be able to set the TXo CV waveform when an output is in LFO mode. Is that expected behaviour?
What do people recommend using as a volt source for CV input calibration purposes?

a773 · 2020-07-22T10:59:25.571Z

I calibrated the txo CV with my decent meter. They are now the most precise CV outs i have and I use them as a reference for calibrating everything else…

toneburst · 2020-07-22T11:05:20.986Z

a773:

I calibrated the txo CV with my decent meter.

I mean the CV inputs on the Teletype itself, and the TXi.

I don’t have a precision voltage source, so was wondering what people use to generate the voltages necessary to calibrate CV ins.

Duksos · 2020-07-22T11:39:08.665Z

Hi I’m sorry for the dumb question if it’s already been answered
I recently used the bom link above I think it’s post 1413
to purchase the parts for a txo and txi from mouser
I received my order yesterday
And there are no pots, jacks or headers
Where do I get them and does anyone know what else is missing from that link
Thanx

thopa · 2020-07-22T11:45:17.537Z

Hi! Where are you located?
Fastest: Mouser
USA: Modular Addict, Synthcube…
Europe: Thonk, Exploding Shed, Befaco…
Always check bom fefore ordering