On 19/08/13 19:56, Caecilius wrote:
On Mon, 19 Aug 2013 18:26:52 +0100, MrWeld MrWeld wrote:
A really DIY approach would be to feed the output of mains transformer,
possibly via a potentiometer, into the audio line-in socket of a PC. A
wall-wart with an AC output (rare, but they do exist) would probably
satisfy most safety concerns. You could record the waveform with audio
software of your choice, presumably at a fairly low sampling rate. I'm
not sure whether a typical integrated soundcard can go as low as 50Hz
though.
That's an interesting thought. Mains transformers are easy enough to
find, or as you say an AC PSU. Maybe I can use a low-end CPU device
instead of a PC to keep it low-power: the raspberry pi doesn't have
audio in, but the pandaboard es does. If I've got time I might give
that a go.

Maybe there are cheap ADCs with USB or serial outputs I could use.
This is getting interesting. Thanks for the idea.
Arduino has ADC at fairly low quality (8 bit I think)


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Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to lead are elected by the least capable of producing, and where the members of society least likely to sustain themselves or succeed, are rewarded with goods and services paid for by the confiscated wealth of a diminishing number of producers.