I have an Ampex ASR 100 serial no. 5100141 that suddenly
stopped working. One minute it was working and suddenly the
circut breaker at the rear broke the current.

Now the circut breaker breaks whenever it's powered on.
If I hold the breaker in, a hum can be heard on speakers but the
dial lamps remain out.

I looked inside, but my limited knowledge of electronics make it
unlikely to be able to fix it. The only visual damage I can see are
two white things that look like resistors but aren't. They are
marked "M2 0.5 k 09" (with, what I think is the omega symbol in
front of the k).

Both of these things have green colored corrosion at their leads
are into the circut board, and one of them is cracked. They look
has if they both got too hot at one time(s) and one got so hot it
cracked. There is no damage to the circut board and these are the
only ones with any corrosion at all.

I don't know if it's worth fixing or if I should throw it out.