Electronic – Anyone recognise this capacitor and its symbol (circle with dot)

capacitorsymbol [~]

Trying to repair an old Hameg CRT oscilloscope and looking at the schematics for the HV Z board I see the following capacitor symbol (in red box):

enter image description here

The capacitor itself looks (vaguely) like this:

enter image description here

I'm not suggesting it is a vacuum dielectric cap, it just looks like this. It's about 2 or 3 cm long with a glass tube and two metal ends.

The symbol is different from that used for electrolytics and other non-polarized capacitors (like polys and ceramics).

Best Answer

It's the symbol of a gas discharge neon lamp. More info here and Here