If all seems OK but no heat the obvious culprit is generally the magnetron. But in my case it was not the magnetron itself but the magnetron socket which I opened and discovered that the RF capacitor had shorted. There are two of these - one in each leg - and each in parallel with a (in my case 10Mohm) resistor. Easy to detect with a multimeter - just compare the two legs. I got a 'used' magnatron (not even the same as mine) for free from my domestic appliances repair shop and with a little modification replaced my old socket with this one. Just to be thorough I also replaced the fuse and HV diode. Still going strong after 4 years. PS: magnetron sockets are freely available online or from a DAR shop.
If all seems OK but no heat the obvious culprit is generally the magnetron. But in my case it was not the magnetron itself but the magnetron socket which I opened and discovered that the RF capacitor had shorted. There are two of these - one in each leg - and each in parallel with a (in my case 10Mohm) resistor. Easy to detect with a multimeter - just compare the two legs. I got a 'used' magnatron (not even the same as mine) for free from my domestic appliances repair shop and with a little modification replaced my old socket with this one. Just to be thorough I also replaced the fuse and HV diode. Still going strong after 4 years. PS: magnetron sockets are freely available online or from a DAR shop.