"Pechs1" wrote in message
...

tube type avionics


Presumably this refers to the TWT's in the radar
system, the EW/ECM systems and not the C3 equipment ?
(the Tomcat was certainly not Korean War vintage!)

TWT's are "tubes" that are encased in steel (think
of microwave oven magnetrons). That was the only
technology at the time that could handle the power
levels required for the radar packages being used.

The other technology for VHF / UHF radios (NAV and
air to air, air to ground, etc), were solid state
designs with NO tubes.

Also the FGC's were undeniably solid state, NON tube
technology.

To be specific, references of "tubes" are as a
circuit switching or amplification device - not
as a display device (ie. a PFD, or MFD).