[time-nuts] Low noise power supplies?

[Poul-Henning Kamp]

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In message <2bf4f4e8c8207ae0f94a7e1a1e63cd14 at quipo.it>, Fabio Eboli writes:

>Il 2013-01-31 06:42 Mark Sims ha scritto:
>> A123 20Ah LiFePO4 cells have an internal resistance in the milliohm
>> range. [...]

Low internal resistance in batteries is an indicator of low noise,
but not a guarantee of low noise.

For instance in wet lead-acid cells, turbulence in the liquid as
the density changes can lead to low-frequency noise, which incidentally
sounds a lot like a pot of stew simmering.


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