Thanks for all your interesting input -- yes the Braun WAS more used here in UK as the American units attracted a huge Import Duty + Purchase Tax worse than the German ones ! Also- German made was easier to get repaired as Germany is much closer to UK than USA !
I HAVE taken off the plastic surround for the actual tube -- it has very delicate thin wiring attached going down into the black handle and inside the handle is a mass of wiring and other things I don't understand, maybe resistors. Where they plug into the power pack sometimes the solder has deteriorated and I have managed to re-solder the connections. I have 6 units -- all retrieved from people who were going to dump them or who had died. I plug them in occasionally to keep the capacitors good.