[time-nuts] EFC tracking

[Poul-Henning Kamp]

In message <4C265BB1.8090902 at earthlink.net>, jimlux writes:

>sound card ADCs, the high end 24 bit ones, are pretty darn linear [...]

That is actually a very debatable proposition, a lot of them are
tracking types that conveniently cover up any lack of linearity
on the analog side of the fence.

The major problem with using sound ADC's is that their references
has absolutely no long term stability, so you will see your EFC
wiggle and wander all over the place, even when it stays perfectly
still.

I would find one of those cheap-ish DVM's with a serial or USB port...

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