Subject: How strong must the magnets in a magnetron tube be?

    So far my understanding of how magnetrons work is that electrons inside a 
chamber are being forced to move around in a circular fashion by a magnetic 
field from a magnet across tuned cavities. My question is how strong must this 
magnetic field be? Logically I reason that if the field was too weak the 
electrons would follow a curved path but would not be curved enough to make 
complete revolutions around the chamber. Must the strength of the field 
somehow correspond to the dimensions of the chamber? What if the magnetic 
field were too strong?

Re: How strong must the magnets in a magnetron tube be?