My Monotron Modification

[KRS1972]

Hello !!

Just started to mod my Monotron so i can use it with my modular synth when its finished.
I use a 9 pin sub'd connector that fits just fine in the Monotron.
With a flat cable i connected the sub'd with the points i need.
(Pitch, Gate, Cutoff, VCO out, LFO out, VA, GND, Vbias)
One wire spare.
Some pictures of the result so far.

Now check some schematics and test on breadboard.

Grt,
Chris

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Description:	Monotron PCB with connection points
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Description:	Monotron case completed
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Description:	Monotron works the same as before with mods
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[KRS1972]

UPDATE !!!

Here is the schematic and pcb layout that i want to test.
VCO out and LFO out works fine. (through my mixer, mono)
Spare wire i want to use for audio out. (not on the schema)

Grt,
Chris

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[KRS1972]

Hello !!

I finished the artwork for the aluminium front and is in eurorack format.
Two layouts i designed, one with the sub'd connector and one complete
with the Monotron. (no ribbon controller)

THESE ARE THE RAW VERSIONS !!

When i have all the parts, a final check.

Grt.
Chris

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[KRS1972]

Today i finished the front panels.
Art layouts are ok, sub'd connector a little bit higher so it fits better in the eurorack.
My second Monotron arrived for the other front panel.
The ribbon controller i will use later.
Here some pictures.

Grt,
Chris

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[Cynosure]

The panels look great. Nice work

Do we get to hear a sound demo after they are both complete?

[the19thbear]

How did you make that good looking panel?

[KRS1972]

For my eurorack front plates i always use anodized aluminum.
The artwork on the panel is done with "waterslide decal paper", you can get it for laser and inktjet printers.
After that i spray a thin layer of vernish to finish it.

Grt.
Chris

[KRS1972]

Here some pictures of the second panel with pcb from the Monotron, pots and jacks.

Grt,
Chris

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[bunker]

Wow! Looks amazing! A couple of questions if I may... What is the function of VA? I checked the schematics and it doesnt seem to be Vbias? I can see from your schematic that you're applying 3v via a voltage reg. Is that voltage normally derived on the main board? What are you bringing it out for? Keep up the good work!!

[Bloxelectric]

Just found this thread & at the time i am contemplating modding a monotribe or two.
Great work here, really organized looking. I'm an electrical novice but even i can make some sense of your work here. Thanks for all the effort posting here & i would be interested to know how the project is fairing up under the duress of use . Nice one indeed.

[Infrablue]

This is GREAT work!

[5c4r7]

Hi There! First off, amazing work! I have to ask, where did you get your faceplate cut and how much did it cost? I sent your design to a company here in Toronto and they wanted $260 to make one for me. I think your mod is awesome and I would really like to make one for myself but, keeping costs down is somewhat imperative for me at the moment. Thanks and keep up the great work!

[new voodoo]

I am SO doing this. Like THIS WEEKEND..well, probably mid-week next week actually (have 37 other devices in the pipeline but I keep about 4 in circulation being made at same time)
PSYCHED!!
Ive kinda been waiting for a reason to use etchant & copper clads, etc Ive got all the stuff and just havent gtten to it yet. AND i have the monotron for it cause I bught one on a whim and its just been sitting aruond in the living room and to be honest-im tired of hearing "WHeeeUUUmmmmWHEEEEuuuOOOmmmp" whenever a friend decides to pick it up.
Since im in the middle of building a modular and need about 10u more of modules (want to end up filling a 100u case), its perfect!!
fantastic.
Cant say enough good about this.
so cool.

[Zodiak]

I was thinking of doing something similar with my three but couldn't work out how to get the connector on the back of the case, but I never thought of putting it on the side