why is the plate supply called B+?

[jarthel]

as title. Thank you.

Jayel

 

[Colt45]

in old radios you had 3 batteries.

A = filaments
B = plate supply
c = bias supply

 

[jan.didden]

I think it was just the pos pole of the battery, "battery +".

Jan Didden

 

[jarthel]

thanks

 

[Sch3mat1c]

Yep, B just stuck around I guess. Alot of amps use fixed bias but I wonder why it isn't called C-. *shrug*

Tim

 

[wopontour]

Yep, B just stuck around I guess. Alot of amps use fixed bias but I wonder why it isn't called C-. *shrug*

Tim

C- is actually at the grid (bias)

Old triple DC battery nomenclature still prevails even in tubesets powered by an AC-DC power packs

A Battery
A- and A+ provide the filament voltage

B Battery
B- and B+ provide the plate volatge

C Battery
C- and C+ establish the grid bias voltage

Interestingly enough the cathode was connected to BOTH the C+ and B- terminals or those batteries yet functioned as totally independant circuits

HTH