MS20 Kit mod/test points non functional

[Mr White]

Also, having some MS-20M kit, envy, I am wondering if there is a way to add FM to the MS-20 kit?

Thank you,

Sjon

I think that getting out vco1 triangle and a cv mixer (to mix incoming keyboard cv with vco1 triangle to vco2 cv input) we could do the trick

don't know if we could expect something usable anyway...

[sjonp]

Hi Mr. White,

The mod looks very clean and I'm excited to implement it. Did you put the 1N4148 diode on the wire coming off of Q3 or Q17?

Thank you,

Sjon

[sjonp]

Mr. White,

Thanks also for the suggestion about FM. The FM mod sounds a lot more involved and I worry that the more complicated the hack the more likely I will damage my synth. I might cut my losses on FM and just be grateful to have the additional functionality of OSC sync and PWM with relatively few parts and not a lot of labor.

Thanks again,

Sjon

[sjonp]

Mr. White,

Looking at Remork's osc sync mod, I noticed the following:

"a wise man on a nice forum mentioned that it would be best to use shielded wires and connect the shields to ground to avoid the oscillators locking when their frequencies are close. you run the risk of them syncing through stray wire capacitance even when the switch is not engaged."

Did you use this in your mod or did you find that it did not really make a difference?

Thank you,

Sjon

[Mr White]

Mr. White,

Looking at Remork's osc sync mod, I noticed the following:

"a wise man on a nice forum mentioned that it would be best to use shielded wires and connect the shields to ground to avoid the oscillators locking when their frequencies are close. you run the risk of them syncing through stray wire capacitance even when the switch is not engaged."

Did you use this in your mod or did you find that it did not really make a difference?

Thank you,

Sjon

I was aware of that but I find using shielded wires to solder smt like blacksonblondies.com

this is tiny phone repair wire, solid core. I kept the two wires far from each other to eventually minimize the thing, don't know but it simply work flawlessly

[sjonp]

Hi Mr. White,

Did you put the 1N4148 diode on the wire coming off of Q3 or Q17?

I think I will also use the phone repair wire that I have on hand and keep them far away like you did.

Thanks again,

Sjon

[Mr White]

q3, it forces vco2 to sync

[Mr White]

here is a pic:

[Steve GG]

I'm surprised by this. A quick prod around with a scope probe on my MS-20M showed that most of these points delivered a signal that I would expect. Of course that doesn't mean they would actually work properly if interfaced with other circuits.

[sjonp]

Mr. White,

Looking at your picture of the front panel of your modified MS-20 Kit, I noticed two toggle switches. I assume the toggle switch between the Total and Freq jacks turns osc sync on and off. What does the toggle switch to the right of the Korg Synthesizer logo do?

Thank you,

Sjon

[Mr White]

other switch toggle between mkI and mkII filters, very simple and effective

was planning to get VCO1 triangle output jack but I don't know where to put it on the panel...

[sjonp]

Hi Mr. White,

Thank you. Did you obtain a Phobya 3 pin connector that Nick Batt used on the Sonic State review for the filter switch?

Thanks again,

Sjon

[Steve GG]

The 3-pin connector is not a speciality item. You can get one from Rapid Electronics or RS for about 60 pence.

Personally I wouldn't bother. I have the option of switching filters on my MS20-M and I use only the Mark II filter. The Mark I filter is just too cruddy and noisy.

[Steve GG]

Oh boy. This forum seems to be absolutely dead. Questions asked, questions answered and nothing.

Signing off.........

[sjonp]

Steve GG,

Thanks for the answer! I have stopped coming by because it has become so quiet.

Best,

Sjon