[sdiy] ASM Capacitors/Bench Power Supplies

[Ian Fritz]

At 03:32 AM 7/31/2003, Neil Johnson wrote:
>Steven,
>
>1. Polystyrene capacitors are needed for the oscillators because of their
>excellent low leakage and stability.  As is the way, they are therefore
>more expensive than polyester or ceramics, which are fine in other places
>(I use polyester for audio path, and ceramic for decoupling).

Does anyone know of a reason not to use NP0 ceramics for the integrating 
cap? I briefly tried both NP0 and polystyrene in my last VCO and didn't see 
any difference in waveshape or tracking.  The NP0 has a smaller 
tempco.  Also it seems to me that the high-grade mica units, although 
expensive, should work better than polystyrene.

Also, PEN (polyethylene naphthalate) and PPS (polyphenylene sulfide) look 
interesting.  Mouser has some CD PPSs in chips, the only ones I have seen 
readily available.

   Ian