In my limited experience magnetron failure is common but testing is not easy or safe. Anyone reasonably competent can check that mains power is feeding the primary of the big transformer but unless you have eht test equipment and some training your testing should stop there and hand it over to an accredited repairer.
The voltage and current on the high voltage side of the transformer is potentially lethal and far exceeds the capacity of equipment available to the handyman..
Answers & Comments
In my limited experience magnetron failure is common but testing is not easy or safe.
Anyone reasonably competent can check that mains power is feeding the primary of the big transformer but unless you have eht test equipment and some training your testing should stop there and hand it over to an accredited repairer.
The voltage and current on the high voltage side of the transformer is potentially lethal and far exceeds the capacity of equipment available to the handyman..