I had a old microwave over which I picked up at Monkey Wards (now out of business) back in 1977/78. It just kept on running and running and running. The "touch" keypad was difficult to operate and it was clear that it wasn't quite as powerful as it was but it was there.
Last week, it stopped. We had already planned on replacing it with an over the over model (more about that in another post) so I wasn't upset.
I decided to take it apart "just to see."
Some comments on what I found:1) That thing was SOLID! It was really, really well put together.
2) It had two (2), two pole (plus pilot) contactors. One was for the "browning" element. The other was for fail safe purposes. The final switching to the transformer was by some kind of triac (there was a diagram showing all the power and contactor wiring -- the "logic" just showed the120 volt and "safety" and sensor interfaces).
3) When I had opened things up, I almost wished I had been a little more careful (because of dirt, I ended up bending the outer sheet metal to get it off). Turns out the Triac (or whatever) had broken off from it's heat sink. Without the heatsink, it failed (the proof was that the wiring to the triac showed some heat damage to the insulation. I was almost tempted to get another triac and put the thing back together.
I "salvaged" a bunch of stuff like:1) The control panel -- it's powered from 120 volts. I might be able to find some use for it. My older girl said she might enjoy having it so I might find some way of getting it powered and not be a shock hazard to her.
2) The contactors (both nameplated for 15 amps.3) The MAIN transformer, high voltage diode, and voltage doubling capacitor.
4) The magnitron tube (still has the heat sink but I want to see how they focused the magnetic.5) The permanent magnets (two flat "donuts". The magnetic circuit was completed by some heavy gauge sheet steel. I might keep them and play with the effects on conductors dropped between the poles.
6) Some power hardware including a combo fuse block and male "slip on" terminal block.7) The MANY microswitches (safety, door switch, temperature probe sensor)
8) The overheat sensor on the microwave cooling fins (NC).9) The thermal fuse that detected whether the contents of the over were on fire!
10) The 50 rpm "stirrer motor"11) The cooling fan.
For now, I will just move the stuff to a "junk box."
If anyone has any projects to suggest, let me know.
Anyway, I figured some of your would be amused by the whole thing.