you might benefit from stabilizing the battery voltage with a LDO depending on the current draw of the device if you use a mechanical sweep generator
I only say this because I have no idea about the current consumption of a gunn oscillator
if its really low it should not matter
i did wonder how an old waveguide system looked like without pcb in everything and coaxial adapters everywhere and now I know
kinda wonder what would happen if you put some ultra precision starrett digital micrometer heads on it and stuff
beware the voltage drop on constant current sources if you do batteries, because I had something with a bunch of AA and discovered a lt3080 current source has a big voltage drop, so I Had to add another 8 pack.
if your equipment is that big you would like the battery brackets I figured out
to make you use loctite prism with sensitizer to glue black cheap polyethylene battery packs to a strip of acrylic (scratch both sides), then glue the acrylic to an aluminum bracket with either acrylic epoxy or more prism + sensitizer. You put screw studs on the bottom with thumb nuts on the battery pack and make sure its aligned so the bottom of the chassis pretty much keeps the batteries in to protect it from mechanical shock. Then you put a layer of thick strong tape on the bottom to act as a insulator for the batteries. If you use studs and thumb screws you can remove the bracket easily. Attach it with silicone wire and put some zip ties on it. Easy to make a 36V source with AA's for those who do not care for converters and small savings at the expense of power systems design ease being outsourced to the shop. If you use nimh you can charge it in series for a long time period I think. The bond between acrylic and polyethylene is so strong you can rip the PE battery case.
![](https://i.imgur.com/6GP0WXi.png)
or if you have the money get the metal battery holders with rivet holes on them