Telex: Teletype expanders


@GoneCaving - We think alike! The top nine (upper right corner) have been tested and verified. You can tell because their knobs are all over the place as opposed to fully counterclockwise. There are two other special cases - but you would have to be good at “Where’s Waldo” to find it. :wink:

I’m pretty sure I’ll keep on with the assembly grind and move the TXi. Perhaps it will go faster as I won’t have the potentiometers and knobs to contend with.



Top left, 11 from the right middle row. Keep up the good work!

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your constant updates are greatly appreciated, and make them so tangible!

sorry if I missed it… but any info yet on the power draw of our two new friends?



the two that are fully clockwise

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A little question just popped in my mind: speaking of connection between modules, will i still be able to use my teletype with my just friends (just type) :sweat:




Built the iiBusboard and iiBackpack this weekend:

Here is the backpack installed on the Teletype:

The bus appears to be totally solid using the iiBackpack. In the video below, each metronome tick is setting 16 random voltages, sending 20, reading 8 param potentiometers, and setting the four internal cv values.

I’m able to change the script to send to dozens of nonexistent modules without hiccup. This is the real acid test to see if there is an appropriate amount of pull-up resistance on the bus. The iiBackpack passes with flying colors.

Last Chance to Add an iiBusboard or iiBackpack to Your Reservation

Let’s consider this the last call to add an iiBusboard or iiBackpack to your TELEX reservation. In the next day I’ll put an order in for the appropriate number of PCBs and components. Again, you will need it if you are planning to connect more than a few modules to the ii bus.

Progress Update

Moving on to the TXo now. Prepping panels today and I will most likely start installing jacks and LEDs before the sun goes down.


@sakul - haven’t taken readings for the modules. I’ve been pretty swamped building them and, frankly, a little nervous about taking the readings and frying something. I’m planning to do it at the end of the process.

@martinmestres - certainly! If you have more than a few modules connected, you will need one of the bus board options to have stable communications between modules.


A user's guide to i2c

OK nice, so in order to connect 1TxO, 1Txi and 1 Just Friend would 1 iibusboard be enough? If yes you can add one to my reservation :slight_smile:



no pressure from my side for this please!
was just making the calculus and wondered if I missed that info.

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@martinmestres - many of us have been OK with three devices on the bus and no bus board. My guess is that you are OK.



I don’t really understand how to add the two extentions to my teletype because the 6 pins connector is occupied by the Just Friend… Do I need some kind of chaining ribbon cable (sorry if the question is a bit stupid…)? :confused:



i2c is a three-wire protocol. Units can be connected in various configurations.

I use three wire jumpers to connect to the teletype and between modules. Each expander ships with one of these cables. Scroll up for pictures.

On the expanders, the three-pin jumper locations are offset so that you can easily connect two to each unit and daisy chain them.

The bus boards allows you to connect everything to a central point.

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I would like to add the backpack to my order as well please, I’ve crossed the threshold number of modules.



Please add one to my order as well !



OK thanks think i got it:
Teletype will directly be connected to the txo and txi by two 3 wire cables and then I would connect my just friends to one of the expanders (if I see well there is a 6 pins block remaining?)?



Please add one iibackpack to mine :wink: thanks !

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also note that teletype shipped with a bus cable with 3 connectors, to attach all the trilogy modules (no idea how well it would suit the expanders with the orientation of the headers though, e.g. ansible’s was upside down). after a certain number of modules the powered bus board is needed as we know now.



sorry, i’m not shure if i need one or the other, i’ll be connecting the TxO, Txi, Ansible and a White Whale.
you can add the proper one to my order :wink:
thanks so much

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Mid-Week Update

Got caught up on some of the ancillary work: making the europower connectors. First had to cut up the cable:

Then had to attach the ends:

I now have lots of band-aids on my hands. :wink:

Was playing around today using two TXi as controls for a Teletype script acting as a simple 8-step sequencer. Couple of lines of script … endless fun.

TXo pulse divider driving the BuckModular Drumfuck. Outputs from the TXi driving the pitch of the Noise Engineering Cursus Iteratas. Random values on the TXo driving various sound shaping parameters on both modules.

Short jaunt to the midwest and then I’m jumping into TXo assembly in earnest. Been doing prep work. :slight_smile:



That sounds like a small, weird factory assembly line tune :slight_smile:
Wondering if getting assembled power cables at this volume wouldn’t be cheaper and saved you some time

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