Moog Music Forum

Thanks Kevin i check your suggestion, I keep you informed.

Fernando.

Hi again, VCF in done!!!, and working, i added a 100k pot to change the ammount of modulation, and include this in the front panel in the left next to the volume, thanks to all, and specially to CZ, now i going for the Vcf audio in, the strigger gate is not very clear for me, CZ Rider did you ...

A picture of the mod

i can't upload the picture, is under the limit of the size, but doesn't works, sorry

Cz Rider thanks a lot for your answer, your mods are great!!!, I put my hands on the mods inmediatelly!,

I keep you informed.

fernando.

i was reading the minimoog service manual filter section, where say

The cutoff frequency control current originates
in an linear voltage to exponential current converter
consisting of a matched NPN-PNP pair Q26 and Q28.
Control voltages from the external input, the keyboard
switches, modulation ...

I was looking the modulation section and I made a mod to get a very fast lfo, adding a capacitor of less value together to C10 in parallel, you only have to put together negative legs of capacitors soldered, the positive leg of each capacitor is redirected to a SPDT, and the common, the center pin ...

heyy, thanks for the answer, ok I discard the filter keytracking, thanks for the information, but i want the cv in to the filter, i want use an external source or other waves, for this machine i think goes to another dimension.

I have schematics, like you know is very easy to get it on internet.

I ...

hi again guys, i want to add a VCF In, (not an audio in to the filter, i want CV in, to the filter) of my Opus III to control the filter with an VCO in audio range or other LFO in other wave, the Opus III only has triangular wave, the idea is use a switch jack to use when you want the on board lfo ...

problem solved, was a wire broked in R17, Amount contour of the filter pot.

Thanks to all

Recently I repair one minimoog(below 10175), with vco2 dead, but now when I connect again after assembly, I can hear that the contour filter ads doesn't work, before it was working. Is very strange.

Loudness contour is ok, except if you open decay in the middle position or away, you can get a ...

problem solved, Oscillator 2 is alive again, was the ic4, an lm741, changed and fixed.

Thanks to all for the comments.

Fernando.

I will check this and will replace the ics related, I keep you informed, thank you very much.

Fernando.

Hi to all, i buyed a Minimoog broked recently, works all less VCO2, is dead, i am thinking on change all transistors and ics related with VCO2, but perhaps somebody can explain to me how to VCO2 generates the waveforms, in the minimoog manual service only explain the new boards, but i have the old ...

for future emphasis problem users, i solved the problem with the help of Steve Jones, Yves Yusson and me of course, i take advice to them about U26, looking again and again the schematics, the problem was in the CA3080, U26, the emphasis trimmer doesn't received the correct voltage, 15 volts, only ...

hi to all i new on forum, i have a opus III, and i am reparing, i cleaned all the pots of the punk foam, but i can't get the filter works good, the emphasis doesn't work, perhaps the emphasis trimmer has a low voltage, i don't know if is normal I test the Cutoff trimmer and get me 15 volts, but the ...