Try our new info resource - "Aladdin's Cave" (Main menu)Just added a separate link to Ash's Dropbox thread (shortcut)
Interesting process Ash especially the coil connecting- nothing like as complicated but I have revived old car horns for a short period by connecting one side to the negative side of a fully charged 12 v battery then rapidly connecting & disconnecting the live terminal so it progresses from a dull click to eventually making the horn sound. Only seemed to work for a short period on a seldom used car horn. I thought it was due to the back EMF somehow reviving the contacts.