I recently purchased three used Rubidium Frequency Standards AccuBeat AR60A on eBay. Two of these were marked as "for spare parts", one of these was just missing the SMA connector in the front but otherwise seems to be working.
However, the physics cell of the other one does not work with either of the two control boards and is likely broken so I opened it to have a look inside and you can join me.


Link to the paper shown in the video: https://tinyurl.com/42uard28