Likewise, I've never seen (or even heard of) an MOT using aluminium wire.I have taken apart Many of these transformers and Never seen one Wound with Aluminum Wire.
Not really true, not 'newer' ones - but an incredibly small number of ovens used SMPSU's (mostly Panasonic ones), and only very top-end models.Newer Microwaves use High Frequency Switching power supplies and the Transformers are on Ferrite Cores Wound with Litz Wire.
I also had a Panasonic MO, on which its SMPS had failed. It only lasted about 3 years, whereas the older Quasar which it replaced lasted over 15 (and only had to replace it because it was leaking microwaves).I've replaced very occasional MOT's, but it's pretty rare - and unlike the SMPSU's Panasonic they don't die if the mag fails
I've scrapped dozens over the years and I have found that about 1 in 5 of the cheap ones were aluminum or copper clad aluminum wound.I have taken apart Many of these transformers and Never seen one Wound with Aluminum Wire.
It's not just common in the cheap no name brand ones. A large part of the big name higher end commercial stuff is aluminum or copper clad aluminum wound as well. Lincoln and Miller, just for two well-known brand names, have been doing it since the 1960's and 70's.The only transformers I've seen with ally windings are in cheapo mig weld sets,
One would guess that they didn't want to price it even further out of the market than it already wasBut rather than make a blanket statement "SMPS-bad, MOT-good", perhaps the Panasonic designs are substandard...... One would guess that as part of the design objectives, you would take into consideration a magnetron failure.