[time-nuts] Low temperature coefficient capacitors for DMTD

[Rick Karlquist]

Corby Dawson wrote:
> Bert Kehren and I are working on a low cost DMTD system.
>
> We are cloning the NBS 106D design with modern components.
>
> You might want to check out PPS dialectric capacitors. (Polyphenylene
> sulfide)
>
> Readily available in many values including large ones.
>
> For stability from –55° to +85°C, PPS is virtually flat over this
> temperature range with a ppm/°C of only 7.

That's a change of almost 1000 ppm over the stated temperature
range.  NP0/C0G is rated at +/- 30 ppm.

Rick Karlquist N6RK