TR-4A: Intermittent electrical blackout

[John Cowan <jfcowan@earthlink.net>]

   Drove out tonight and after about a quarter mile, car stalled and
electrics were entirely gone, as if the battery were dead.  Coasted to
safety, waited a minute while jiggling wires, etc.  Hit the mechanical
starter solenoid switch and she lurched.  Got in, turned the key and
everything worked fine.
   Drove another quarter mile and the same thing happened again, except it
didn't come back at the ignition switch until a minute after the starter
mechanical starter solenoid worked.
   Car has a known problem of non-functioning turn signals when the
headlights are on.
   Any ideas?
Thanks.
   John Cowan