DIY EPR/ESR spectrometer - general overview+dummy-load?

[ChristofferB]

Hi all!

I posted some beginning musings over building my own electron spin resonance /electron paramagnetic resonance spectrometer some time ago.

It's kinda like NMR but easier, because it requires lesser magnetic fields, so it can usually be done with permanent magnets and still reach usable results.

Now that I've gotten a gunn-diode module, i've gone a bit further with the design, see attached.

The main idea is that the lower piece of straight waveguide is a cavity (akin to the resonant coil in an NMR head) in which the sample is placed in the mag. field. and this field is swept by slow AC, and an output in varying energy is siphoned off by the directional coupler and sent to a recorder, as function of field strenght.


Does this look sound? I'm a bit concerned that there's no downright load for the energy, and so the gunnplexer might be punished badly by this setup.

whatcha think?

thanks for the interest!