No regular shops left, but these are not rocket science either (if you have some more than basic electrical background)...
The main issue with mine was power cord insulation that had turned to dust, so a no brainer... I was concerned about the transformer to head cord, but it seemed to be made of different materials/dielectric than the AC cord (as I opened the head, looked at the insulation on that end of the cord, and saw it was still supple and intact so I tested/continued)... If that cord was bad, it would have been real trouble as the wires headed straight down into the tar potting material inside the housing, but after doing short tests (and measuring the resistance of the transformer secondary and primary) it seemed OK... With a new AC cord + fuse installed, then powered it up on the bench and measured about 570VAC (I think I remember it being something like that)... So that's a start...
On the grid end there was much corrosion under the wire nuts connecting the HV cord to the thin grid wire ends, so I cleaned them up (be very careful as these lead wires are thin and maybe brittle, and don't allow the heavy cable to stress these while installing and secure well), tested them together and there was light!!! Then it was off to restore the rest of the head...
If you have trouble getting the transformer housing open (stuck like a giant clam), turn it upside down and hit it with a heat gun for a minute or two, to heat the tar (that may have dripped a little into the cover seams) and pry the corners each a little at a time until it pops off...
The temp regulation I upgraded to was a big help getting consistent exposures from these, because before, even with a shuttered lens and leaving it on throughout the printing session, exposures would bounce around quite a bit, so it was a big help...
Go through your steps, and see if the grid lights up...
Good luck!!!
Steve K
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