AL1200 RECAP: Any opinions on ohmite wirewound resistors for HV bleeders?

[357]

I'm doing some spring cleaning and inspection on the al1200 and the ohmites white lettering is wiping off on the most of the inner resistors....the others are ok mostly.
Does that mean anything like they are getting too hot?

Also the board seems a bit saturated with something? It wasnt there in Nov 2022 when I put the new caps in.
I think its just rosin from the solder

 

[nomadradio]

They are designed to get hot. That's the point of using a ceramic body. Power resistor design is a tradeoff between how hot its materials can be allowed to run, balanced against the physical size. The more surface area, the less temperature rise. The printed ID stuff will flake off eventually. A fanatic would change the bleeders to a higher resistance value and reduce the heat that way.

That kind of resistor almost never fails without first being massively overloaded. The steady heat from this service should not be a problem.

Just remember the rule of the shade-tree. If it ain't broke, keep fixing it until it is.

73

 

[357]

been running pretty hard. Just a annual check-up.
The fuses powering this thing have even been suffering.

 

[nomadradio]

That's a manufacturing defect, like the wrong brass alloy, maybe?

If it had been overworked you would see evidence of high temperatures. Too shiny for that to be the case.

73