[sdiy] integrator / capacitor leakage

[JH.]

Hi Magnus,

>Let me point out that these may not be the same. You are trying to reach
>precision, and leakage is one of several things to battle.

Yes. If I have electrostatic coupling to a 50Hz signal in the integrator
for instance, the VCO will cycle, but the waveform will not be perfect.

>External sources of leakage includes creep-voltages from power-supplies,
signal
>etc. These are due to the leaking in the PCB and eventually also on the
dirty
>surface. Some of this can be solved by providing a guard-ring on both sides
of
>the mounting-hole, keeping the same voltage as the pin to be guarded.

I'm making these connections above the board (bending IC pins upward),
which should even be better than guard rings.

JH.