Learned a lot the past few weeks/month in this forum and decided to build my own Theremin. After a few initial problems (concerning finding the wright parts and a few building faults) I could get everything working thanks to the search-function of this forum.
BUT, I can't seam to figure out the last problem I have: If I boost the volume via an external effect I hear the 3 oscillators as "bleed-though" in the audio path. Waving over the volume antenna makes the volume oscillator (which I hear) go up or down in pitch. So I know that's working properly. If I come to a certain point via the tuning I hear the VCA rapidly go up/open with the theremins audiosignal as it should be and immediately close again (sounds like a "pop", but changing my hand over the pitch antenna or changing the wave or timbre settings I can hear that it's the theremins audio with rapidly opening/closing VCA.) If I leave the tuning there and come close to the volume antenna I can "make the VCA pop" when coming close to the antenna. Works better if I make a quick hand movement. If my hand moves to slow the "pop" doesn't occur at all. (same for tuning the coil, or tuning via the panel.)
I already replaced and tested the LM13700, which was/is working as it should. Also the wave and timbre options work properly.
I also tested and replaced the (already working) diode D1 in the volume antenna circuit.
And I tested if maybe the volume antenna is too long or short. But that isn't it either.
Could it be that maybe C12 is faulty?
Or is it because I'm using 3 and not 4 coils for the antennas. I first read that one should use 3 coils when using "Coilcraft Slot-Ten" Coils, only after I build it I read in another post that this only applies when building on a PCB, not when building on prototype-board. But it still seams that the pitch and volume oscillators are working like they should.
I also wonder if the bleed-through is normal? I boosted the signal quite a bit to hear it, so concerning that the normal output is line-level, this might be normal.
BTW: I am using the "hot-rodding your etherwave" schematic with a few changes suggested by user "Thierry" when using "coilcraft coils Slot Ten" in another post on this forum and a few suggestions from this post http://www.thereminworld.com/Forums/T/29123/just-built-etherwave-doesnt-work?Page=0 like the C10 and C11 = 100uF to ground from the 3 schematic.