I am playing with options for a 10 MHz standard and stable frequency reference for the microwave build. There is quite a range of options. One thing there isn’t is an off the shelf, reasonably priced and easy to use portable standard. That’s a lot of requirements in one sentence.
Now if I could just find some cesium, I could build the ultimate atomic standard. NOT! The closest is a rubidium gas frequency standard, but it has faults (high current, long warmup) as far as being easily portable. Very popular today is using a GPS receiver to stabilize a more earthly standard. But GPS needs to have a location for its antenna to see the sky and hear the satellites.
I decided to home my efforts to a heated oven (temperature) controlled crystal oscillator OCXO. It takes a while to warm up and stabilize but it is portable. I have ordered several OCXO modules from EBay. These items are not plug and play, but can be the basis for building what I need. The first one I have in hand is shown in the first picture and I just saw another one in the NTMS reflector that I ordered today, 2nd picture. It may be a month away as it is sourced from China.
All subject to change of course, as I have not started any construction. I just like the planning as much as the doing, and throwing my ideas on the table for review.
UPDATE: The second OCXO was shipped the same day it was ordered... on potentially the slow boat from China. Results can vary, but I'll post a note when it arrives. I also received notice that my DEMI L144-28IACK shipped today from Florida.