Turnip, yes, in fact I did the "nail" thing yesterday. Well, two thin strands of a mains cable. Watching current on my PSU, rose from 30mA to 1.15A, but no backlight. Two fuses on inverter both O/C, so two more pairs of strands were applied. Screen lit up and menu displayed. Portable DVD player and scart lead gave good sound and pic. Dragged in an aerial from bedroom and tried to tune, but (as half expected) no Freeview. Half the tact switches on top panel O/C, so back on and it will be returned to amenity site for the next lucky "owner".
When I collected it, it was stood outside and wet, but it had obviously been very wet for a while before. Rust on tuner, but also on cover panel for inverter. I did not really expect much joy, but a minor challenge to keep the grey cells working.
I bought the stereo microscope (10Xs, 40Xs) back in the early '80s. At the time, I was fixing Gundig Tuner-IFs and tuning boards (who remembers the 29502-003-21 tuning board?) and they helped me locate all the dodgy dry joints. Once I learned how to solder them for a permanent cure, I found I could do a fairly quick and very reliable repair which I turned into a mail order business through TV mag. That plus local Grundig repairs plus 'scope repairs kept food on the table for a decade. Not too bad for an escapee from the pottery industry, cheesed off with top management.
Les.