NC pins on submin tubes

[engels]

I'm making a PCB for a preamp with 5719 submin triodes and stumbled upon something very minor. The tube is a triode with 8 pins/legs. A couple of them are non-connected and probably made for a better support only.

The question is - when I solder them, should they remain non connected or sould I tie them to a ground?

What i see inside the tube is that those NC pins go to the first (lower) supporting disk (mica?) and end there.

5719 Sylvania datasheet

 

[dhaen]

Unconnected is the norm;- unless someone can convince us that the 5719 is a special case for some reason....

 

[unclejed613]

tying them to ground wouldn't hurt anything either if your circuit is operating in the audio range, and like you thought would add mechanical support to the tube.

 

[wa2ise]

I've wired the NC pins (wires) to the nearest neighbor if it is the plate, or the cathode, or the ground side of the heater. A little less capacitence (shouldn't matter in audio work) and it requires a bit less worry about the wire leads shorting to other wire leads, as they are going to the same place.