finally a working setup
Added 2024-08-30 18:21:41 +0000 UTCI've been playing around with my huge magnetrons and finally came up with a working macrowave setup. I used a vintage "radarange" microwave to house the magnetron, which fit perfectly in the waveguide without modifications. Playing the balancing act of powering it up without melting my variac or the tube filament turned out to be tricky though. My variac is rated for 33 amps yet I was pulling 100 amps in the previous setup. In the new configuration I'm keeping it around 80A which should be fine for short runs.
An annoying aspect about the magnetron is that its filament has a derating curve when power is applied to it. That means I have to turn two variacs at the same time to keep it from melting. However, at full power, the filament stays hot on its own, so I built a cursed relay setup to kill the filament power while sending full power to the macrowave. It works so far, but I worry I might get some unexpected effects when I start tossing things like metal and fire into the oven.
Today I'm going to try squeezing a little bit more power out of the setup, as well as mount an "in microwave" camera, and after that, it's full send for filming the experiments!
Stay tuned!
Comments
Can you measure the resistance of the filament to estimate its temperature? Should be pretty straight forward to do with an arduino in real time. High voltage isolation issues aside.
Andomedo
2024-08-30 20:55:45 +0000 UTCi will do my best! the oven does an excellent job containing the field, but eventually i want to open that up and put my faraday cage to the test lol
styropyro
2024-08-30 20:42:59 +0000 UTCit's an old GE volt-pac rated for 240A 33A continuous duty
styropyro
2024-08-30 20:41:50 +0000 UTCthat toroid is actually the filament transformer for the magnetron! I had to add a bunch of insulation before winding on the coil because it has to hold off -9kV to the core, since the anode of the magnetron is what is grounded.
styropyro
2024-08-30 20:41:07 +0000 UTCProfessor Ophelia observes her students lab work - grade pending. Then there is that Tim Hortons size toroidal choke. So how fast do we cook a hot dog in that I wonder...hmmmmm.
Ric Beme
2024-08-30 19:10:49 +0000 UTCWhich variac do you have?
Jeff Larson
2024-08-30 18:29:46 +0000 UTCThis rules so much
Gems of Science
2024-08-30 18:27:16 +0000 UTCbe careful with digital electronics near high power microwaves, could destroy the Wi-Fi module among other things
Nick2116
2024-08-30 18:24:06 +0000 UTC
