Monotron midi mod connector confusion

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rarara
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Location: glasgow

Monotron midi mod connector confusion

Post by rarara » Mon Jan 21, 2013 6:27 am

Hi, am about to pop the beatnic midi-if mod into my monotron. this will have 6 wires between the monotron and the midi-if pcb. i saw (and now can't find :mad: ) a picture somewhere of a nice tiny low profile 6 pin connector (black rectangular plastic) that was fitted to the monotron casing at the back, and allowed the midi-if to be easily disconnected when not in use.

can anyone point me towards what that connector is called - maybe on digikey or the likes?

also, while we are at it - anyone able to explain how the monotron ribbon keyboard can be saved with the midi-if mod? there is an explanation on the beatnic website but the japanese translation has me stumped. ideally it would be good to not destroy the ribbon functionality

thanks

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mmtakeda55
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About pictures of connectors.

Post by mmtakeda55 » Sun Mar 17, 2013 3:22 pm

I put pictures on to my site
http://beatnic.jp/manuals/monotron-midi/midi-kit.html

it's just a signal connector that used in PC or so. most cheap one.
Mouser part #649-68683-307
something like this. I cut them 5X2 size and I dig channel to make it fit onto monotron enclosure. I also cut out he monotron enclosure itself.
I can't recommend it, but thre is no other connectors can put into monotron. because of there is no room to put something in.

I've wrote another methods to adapt it to Monotron Delay.
http://beatnic.jp/manuals/m-delay/index.html
I also write more for not to kill the ribbon by using digital transistor.

Check it out and please welcome it.

(So sorry to late to write back to here )

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Jackdamery
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Post by Jackdamery » Sun Mar 17, 2013 3:46 pm

mmtakeda55 what does the bias do on your MIDI if kit? I tried to make my own midi to cv control of the monotron using an arduino and a mcp4725 DAC this weekend, but I can't seem to properly control the pitch.

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mmtakeda55
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About bias

Post by mmtakeda55 » Mon Mar 18, 2013 2:05 am

I use bias as to make tune right. You may check more basics about analog matters around op-amp or so.
you may found some hint around there.

opamp needs 2 power source, basically. it's positive and negative. And there should be center voltage between them.
that's the reference point of working opeamps.
if power sources are same voltage(positive and negative), the center voltage should be 0V that we call it as GND.
but monotron has positive power source only. so we need something center voltage to drive opamps. that's bias.
this voltage will change the actions of opamps. I change it to change the tunes.
monotron's bias is around 1.3V or so, because the opeamp that monotron uses can't swing 5V, it's around just under 4V or so. but it can output 0V. so 1.3 V is good as bias for its opeamp.
around there is most funny point to learn about analog matter. try that!

My new documents, MIDI-IF for Monotron Delay is using this technique more positively . check it out, please.
Feel free to send me questions, always.

rarara
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Joined: Tue Oct 16, 2012 5:48 am
Location: glasgow

Post by rarara » Tue Mar 19, 2013 5:19 am

hi motohiko - still need to get back to you about my midi-if mod. been modifying my x0xb0x for a few weeks now ( :waah: ) so not had the opportunity to try and get it working. maybe another week or two..

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