Tube socket details
This picture gives a good view on all devices used to get a RF cold cathode. Capacitors are mounted between the two filament (one is also cathode) connectors. The cathode is grounded via a brass strip. The "hot" AC-side of the filament is decoupled by three capacitors of 1 nF, 10 nF and 100 nF in parallel. This side of the filament is also connected to a quarter wave open stub of RG58 coax, effectively grounding any rf still present.
Note the improved grounding of the top plate of the Ug2 capacitor. The top (ground) plate actually consists of two identical plates on top of each other. A thin brass sheet is mounted between these double-plates. It protrudes on both sides and is grounded by means of two brass bars, one on each side of the capacitor plates.
A little piece of curved brass is connected to the middle plate of the Ug2 capacitor. It has a distance of approx. 1 mm to the chassis. In case of an anode flash-over any high voltage on the screen will be effectively short-circuited to ground, preventing damage in the G2 power supply.
The grounding of the topside of the Ug2 capacitor plate can also be seen in detail. Notice the two plates on top with the brass foil extending. The brass bar on the left pushes the foil to the chassis, providing excellent rf-grounding. The same principle is used on the right side.