>> Is it not a case where you just record the sound and analyse it later in the
>> office? does it really need to be analysed on site. I would have thought a
sound
>> recording with pole ID# would have been sufficient. with high performance
>> analyses later.

>Ooops, we're drifting off topic here!  Even so, I'm sure no-one will mind a
>brief reply.  Basically, yes, it could work that way.  At the moment our pole
>testers test several poles a day, marking the defective ones appropriately,

Well I was assuning you would use a PIC for the data collection. However I can
now see why you would want to do it the way you propose. I would also guess that
it is a case of not needing to make it absolutely micro miniature as it could be
connected to a car battery in 99.9999% of cases, at least for recharging most of
the time. from this I would take it that you could happily use the PIC with the
largest RAM etc.

Just how accurate does the FFT need to be? I do not have expertise in this area,
but if it was to show as a "bargraph" on a graphics LCD (spectrum analyser
style) does this save you anything? I assume that the good/bad decision would be
made by someone looking at the picture to decide if the "out of band"
resonance's/artefacts are sufficient to condemn the pole.