Скачать или смотреть DIY Hull Magnetron Made With a Regular Vacuum Tube

UPDATE:: I tried the DY86, pretty good results!! the DY86 or similars are quite easy to find, i drove the anode at like 7mA @ 66V (solenoid off) for the most radio waves, regular filament drive at 1.4V, you still need a chunk of current on the solenoid to achieve magnetron state, lowering the anode current means you can use less current on the solenoid but 7mA seems ideal for this tube, i used also an antenna and a small choke coil to get out the signal, my field strength meter still picks it at like 15cm from antenna to antenna, no need to stay super close anymore, i've also noticed that concentrating the magnetic field around the top of the anode improves the signal as i suspected, infact the closed end of the anode is best to be voided of electrons, the cylindrical part of it will still receive the mag. field, a picture here:: https://imgur.com/a/4M2qR7w apparently the DY86 can be used OR as a rectifier OR to make X-rays OR as a magnetron.... aahhhh tubes!!
::END_UPDATE

About the tubes, i tried that damper diode (EY81) initially, yes, the space between the anode and cathode is too small, i pushed the variac up to like 15Aac on the solenoid and the anode current on the meter reduced of just like 2-5%, obtaining just the solenoid almost smoking, it was probably the electrons that took a slightly longer path bcs of a bowed trajectory... once i tried the AZ41 i needed just 6-8Aac to reduce the anode current significantly, but you still need a minimum current on the solenoid to have an effect... if i push the variac further with the AZ41 the anode current reduces a bit more but the radio waves production goes also a bit down

Yes, it's a bit unstable, there still are some factors i don't exactly grasp, like maybe the temperature change or warping of the anode or also filament (that happens also without any magnetic field so regular conduction), but using AC for the coil you easily cross the critical conduction point (Hull cut-off magnetic field) multiple times per second, that makes the most radio waves, if using permanent magnets or DC you can only play with the other variables like the anode supply or maybe the filament, rendering the adjustment way more critical and limited, on the other hand if using DC on the solenoid you can steadily pass the critical conduction and zero the anode current, probably requiring a way higher voltage to reach critical conduction again (like an oven magnetron), infact i couldn't do that here, i just reduced the average of it although i surely passed such point

Anyways the amount of radio waves produced is microscopic, it may be in the order of tens of microwatts, but it works at low voltage and all of this has been fairly easy.... i'm honestly also a bit surprised it works LOL