[sdiy] vcr delay line?

[RMC]

> ....what is this thing?

It's a piezo-electric substrate whereby acoustic waves are generated on its 
surface due to an input signal, travel on its surface at a velocity a lot 
slower than the speed of light in that substrate and generate output signals 
some time later.

Unfortunately the delay is measured in terms of 100s of ns or maybe a us or 
so - I can't remember the figures but it isn't long enough to be of audio 
use.

RMC, England