Rightyo, I have built up a Magnavibe, and amazingly it seemed to work the first time (once I had sorted out a grounding issue between jack socket and one of the pots). A very, very subtle effect that I am putting down to me being impatient and not waiting for the appropriate LDR to arrive in the post (should be 5/20M - I used a leftover from a Tremulus Lune which is a 5/500k). However, I socketed both the LED, transistors and LDR so it shouldnt be too much of an issue to replace.
A question - what would be the likely effect of changing the MPSA18 for another transistor? Is it even something worth playing around with?
Here's a couple of photo's of my build. I think I am getting neater at the lead dress, but how to fit a battery in there too is an absolute mystery!
Cheers,
Adam