Local Battery talking, common
battery
signalling antisidetone. For use on nonpolarized ringing lines.
B1A
ringer, 387A capacitor, 104A coil, 266A inductor. Hookswitch is
labeled "lift plunger to dial or talk"
Note that most 307 variations do not
have the party line hookswitch.
Looks pretty much like any other 302
on the outside.
The right plunger is lifted to dial or talk.
Inside, we see the components of
the H7 mounting. Base is dated 5/47.
