Alan writes: > 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, and the next day they move on and test another batch. Off-line processing would require a change to this working practice, with the likelihood of having to return to some of the poles the next day to mark them defective. This wouldn't be much of a problem if it should prove necessary. But you know how resistant workers and unions can be to change! If we can achieve it, we simply want to provide the testers with another tool in their toolkit to help them test a pole better. If we can't achieve that, perhaps because of the complexities of the signal processing, then maybe we could go to something like you suggest. Thanks for all your comments, folks. Steve Steve Thackery Suffolk, England. Web Site: http://www.btinternet.com/~stevethack/