I picked up an F-14 and discovered the upper diverter coil was fried (the sleeve had melted into a ball inside). I've replaced the coil but before I fire it up I'm looking into what may have caused it to fry.

Both the Q77 and Q76 transistors had been replaced by a previous owner. The U50 looks original.

Before pulling those two transistors out for testing, I decided to check other components in the circuit, and discovered that R102 was reading at about half of what the same resistor in the other solenoid circuits were reading (about 1k ohms rather than 2k; it's supposed to be a 2.7k ohm resistor).

I lifted one leg and it read over 2k. I replaced the resistor and and the new one also read about 1k in circuit.

Any ideas on why of the six similar circuits only this resistor would be behaving this way? Is it even relevant?

Since both transistors had been replaced before, I'm wondering if that's not the problem.
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Thanks. I just tested both transistors on the board and they were OK. How would I know if U50 was shorted?

For the record, I never figured out whether the resistor readings were relevant....I replaced both transistors and the diverter is working again. To hedge my bets I've disconnected the 50v power and replaced it w/ 25v from the pop bumper, and am going to put a fuse in too.