OT MK1 Love Thread


some new love for the mk1 OT!

wut do yall thank?

Customising LCD display
Octatrack mk1 v mk2

Did you change the screen or is there an option to invert it somewhere?


its been changed


It looks nice


I would love to change it too, although I live in Argentina so I would need to get ahold of the part and have someone do it here… did you replaced yours?


no i hired a pro. its not as easy as the monomachine, which is just a drop in. this one requires some special voltage converters.


Too bad it’s not a drop in. I’m comfortable working on my own gear within reason and could probably do it myself (couldn’t be anywhere near as tough as installing the Tubbutec mod in my Juno last year), but I wouldn’t want to take the risk of messing up the OT - too expensive to mess with, especially with all that SMD stuff in there. What I WOULD consider doing is getting a replacement LCD (just in case I cracked it during the mod), peeling the polarizing sheet off and cluing a new one on rotated 90 degrees, to get an inverted LCD. I’ve added a bakclight to a Gameboy before, which is basically the same except you peel the foil off the back instead of the polarizing film of the front, and it wasn’t that bad but there’s definitely the chance of scratching or breaking the LCD if you work to fast. But you’d end up with a drop-in inverted screen.

EDIT: https://www.youtube.com/watch?v=jHiM4ph6kUI

To invert the image,you put a new sheet on but rotated 90 degrees relative to the original.


The new OS has reinvigorated my love for my OT. I had been avoiding it a bit lately due to the lack of trig conditions, but man oh man… this thing still slays all these years later. TRC, slices, plus the 3 LFO’s is just nuts. Its so easy to get a million great variations on a pattern happening while keeping everything musical.

Just did a battery replacement as well. Very easy to do on your own, maybe 10 minutes, and cost like $3.00 for the battery and wrench for the front panel screws.


How dare you have been avoiding the Octatrack, oh well, at least your back together again…:sweat_smile:

My silly fantasy for the moment is that every seven years they just rerelease the same Octatrack again with new buttons and fader, and one new feature, because it’s still kicking ass… :wink:


So I just used a device like this:

I pulled the ground pin from the header on the display and just wired this thing in there. There is an ISP header close to the display so I just tapped the 3.3V there



Hi! These voltage regulators is what I think i may be missing.
My screen illuminates but there are no graphics!
Is this what the technician you hired ended up putting in?
Do you reckon you could snap some shots (front and back) of the UI board please?

This is the screen I got, I think it might be the same as yours:


@ alien_brain

What lcd module did you actually use (part number would be helpful)? Did you use step up converter only to Vdd only or to Vee too? How about contrast voltage? Many questions :smile: I know but would be great to know.


@ matthismeyer

Did you manage to make it work? This is module is one of my candidates for the project.


I managed, but had to delegate it to a competent electronician.
Had done it for my machinedrum but Octatrack was way more complicated as you need the step down voltage converter mentioned in this thread (got it on amazon)
It bugs out sometimes and the screen freezes but works fine after a restart.
I got the screen from Adafruit.


*step up


Thanks for the reply. Well replacement in MD is fairly easy indeed. Did you use step up only on Vdd?
I am asking as I am a bit confused about Vee 3.3 negative voltage used in the original module (pin 18). How about the contrast adjustment after your mod? Is it fixed or adjustable?


It appears ET was sent home, he’ll be back in 999 years :sweat_smile:



This is one cool modification though. Probably works on many devices with screens like this. Got me wondering what screens could be replaced in my setup with some nice monochrome goodness :smiley:


you are right. seems like a dead end :slight_smile:

i did this one


and a few others

but these were fairly easy ones. essentially swaps.

i am thinking of upgrading A4 and OT with lcd negatives. oleds i guess would require a micro controller to “translate” the instructions, which is beyond my spare time capacity to learn.


The Yamaha looks awesome with that display. So crisp!