[Milsurplus] HRO question

[Ben Nock]

I am just retsoring an HRO but have a question. =


this set is an early one, no S meter, no xtal filter,   456 khz if
line up:   6D6/6D6/6D6/6C6/6D6/6C6/6F8G/6C6/6V6
large metal lump next to aerial terminals ( cannot be output =

trannie as its the usual ht feed and connection to anode on the rear wall=
)

question is.. model ? and why is the cathode of the o/p valve =

not returned to ground but connects to a pin on the power lead. =

(is this for some form of neg bias ? floating ht supply ?)

any advice welcome. =


Ben G4BXD.