The FM mod for Cocoquantus is done by adding five input screws, each wired to a ready-to-wire CV input pad on one of the quantussy oscillators. I arranged the screws in an arc, following a photo I saw. There is plenty of room, but be careful with placement to clear everything below deck. The left-most screw on mine comes very close to the nearby input jack. It’s a simple mod for anyone with soldering experience. The new CV input is sensitive and sweeps the oscillator over a very wide range when patched directly to one of the triangle wave outputs. Sometimes I patch in a potentiometer with alligator clips to attenuate the CV.
Detail of the new inputs
I could not find an exact match for the screws at two local hardware stores. The originals must be #4 brass wood screws, 3/4″ in length. The stores only had shorter #4s. The 3/4″ length ones were #6, so that’s what I used. I managed to fit #4 flat washers under them.
FM Mod Wiring
White wires run from the screws to pads surrounded by white squares. The pads are easily identifiable, since these are the only ones inside a white square. Two of these are visible in the photo.
Hi Richard,
Do you by chance know how hard/easy it would be to replace the screws with banana clip plugs like the coco 2 has?
Thank you
Paul
Paul, it’s impossible. The screws are soldered directly into the coco’s printed circuit board. The board in the coco 2 is designed for banana jacks.
I like the screws in my cocoquantus version one. It’s no problem to patch them with alligator clips. If you have a coco one and want a coco two, I suggest selling the old one. I’m keeping mine forever, because it is a rare, handmade machine and there will never be any more made.
Thanks Richard! I agree with you about keeping the old one just like peter intended. I have an opportunity to buy 2 original Coco’s and was thinking about modifying the second one. But if they are soldered into the board no worries. I am also going to buy a sidrazzi (the version right before the new one) I believe you have that one as well. Would it be possible to change the screws for banana or even better 1/8 jacks?
Thank you so much for your help.
Paul
I don’t have a sidrazzi. You might be able to change the screws on it, but they are just node points, meant for touch control. Why not get the new sidrax, that has banana jacks?
http://petermopar.blogspot.com/2013/09/tetsid-axe-sid.html