Later microwave ovens often had another black thing with 2 leads, and a symbol on it similar to that for a tranzorb - they frequently fail S/C for no apparent reason, if you're lucky the fuse pops before you get shorted turns on the transformer.
Another cause of blown fuse is the safety interlock switches on the door - 2 of the switches cut the mans, the third is a failsafe that shorts the transformer primary if both the breaker switches weld shut.
Slamming the door shut can cause bounce on the shorting switch - another potential fuse blower.
The most expensive part I've ever bought for a microwave is a bulb, one plus side of living in a flat is the communal bin rooms, microwaves get dumped every now and then, if the dish etc is missing I scrap it for spares. There's a couple of spare microwaves stored in the garage, the most recent find was a fully working (except the bulb) grill/microwave which I took indoors to replace the existing one - but that's not showing any sign of conking out just yet!
If the fuse is blown; pull the wire off the HT tag on the transformer and try another fuse, if that's OK you then have to eliminate the diode & capacitor.
The HT winding is 2kV at 1/2A - it could probably show Old Sparky how its done!!!
Legend has it the concept of cooking with microwaves came when someone was working on a microwave dish with power going to it, and the chocolate bar iin his pocket melted, showing the value of microwave for heating things.
The legend never says how much power was going into that dish.
Remember though that power drops off significantly with distance. You need high power to bounce a signal off the moon because by the time it hits the moon, the power is miniscule, and made even tinier by the return trip. Benig right next to a high power transmitter can be a bother, ifnothing else it may overload your receivers and audio amplifiers may start rectifying the signal so they act as "crystal" radios, but not that far away, the signal has diminished by quite a bit. The fuss over cellphones is because the power is really clsoe to your brain, even if it was kept on the belt and operated remotely, the power would be significantly less.
All the microwave point to points I've worked on have had transmitter outputs in the hundred milliWatts range. A single dish can have many transmitters multiplexed, but there is nothing approaching enough Watts to heat anything up significantly.
There is no RF increase near the base of a tower. The antennas transmit sideways. Downward lobes were eliminated by spacing bays 1/2 wavelength (180 degrees) apart, rather than a full wavelength (360 degrees). The beam tilt determines where the energy meets the ground.
School towers are not dangerous to students, provided they are above them.