EUR 7.-Another EMP question: Can you make a reusable EMP generator?

EMP is usually produced when a nuclear weapon is detonated; this wave fries all unshielded electronic circuits in its path.

There is another way of generating such a wave using some devises like EPFCG (explosively pumped flux compression generator), but as you can see from the name it mainly depends on an explosive charge and it is not reusable (destroyed after use).

I’ve came across another device called “HAGII-C” which produces EMP with no detonation involved. (Attached picture)

The question:

How does this device -HAGII-C- work (what happens inside its shell)?

What is the physics concept that this device rely on?

What are these rings for? And why are they up there? (See attached picture)

What is the frequency of this wave (pulse)?

Answer requirements:

It could be understood by collage students.

Draw a simple diagram explaining the device (like a draft or a schematic drawing).

Thank you.

P.S.: EMP = Electromagnetic Pulse, and it is not produced via passing an electric current through a solenoid wrapped around a metallic rod or something (this is called electromagnet).

I do know now about the explosively pumped flux compression generator (thanks to Mr. Cesare Borgia), so please do not provide more answers relating to it.

Picture: courtesy of Wikipedia.