Sir rico4295 . . .
Observations and suspicions . . . .
The unaffected R2 and R3 units are being of CARBON deposition / SPIRAL laser trimmed construction .
The affected R1, I
VERY highly suspect, to be of METAL film / SPIRAL laser trimmed construction.
They hold up
QUITE well under overload . . . despite the apparent coincidental cosmetic degradation.
I have seen metal film units running at an orange glow ( viewed in the dark) state of overload and
STILL holding their resistance value as well as a much larger power wirewound unit would do.
39 ohms is still a good and valid estimate of its initial as well as present value.
Seems like you need to make a resistance check on both sides of the resistor to see which is being
closest to ground potential, thereby suggesting that side is towards the overloading direction , that is trailing towards a bad component, which is responsible for the overloading of that R1 resistor . . . . which is still hanging in there . . . .
VERY-VERY begrudgingly, however.
Is that a fried inductor just northeast of R1?
I am seeing no symbol annotations akin to L? or T? being made around any of the 3 of them.
Plus . . . the liberal deposition of excess goober-loober in their immediate proximity, suggests of them being MECHANICAL attributes, not electrical / electronic, particularly the due EAST one, with its protruding shaft.
73's de Edd
.....