#even vco

[coolmusicstickers]

Befaco

[fishboytech]

Added a heat shrink “breeze shield” around IC2 on the Befaco Even VCO main board. Used a large diameter piece to fit around the whole IC socket, then added a smaller diameter piece to the top to seal it off (pinching it with pliers while it was still hot). Then trimmed down the top with scissors. But why?? To try to improve the VCO’s temperature stability. Under that IC socket lives the temperature compensation (”tempco”) resistor, and the exponential converter transistor pair (”T_SENS” and “QQ_1″ on the schematic, respectively). They are both small surface mount (SMD) parts, so they can live in that space under the IC socket. By adding this heat shrink around all those parts, I hope to remove heating/cooling by air convection as a source of VCO instability. The parts will still need warmup time, they just won’t cause the VCO’s frequency to respond to brief heating or cooling by air currents any more (I hope).