On Thu, 13 Apr 2017 20:50:14 -0400, William Bagwell
wrote:

On Thu, 13 Apr 2017 16:43:02 -0400, wrote:

...VERY much simpler slip rings...

Indeed! Built a crude slip ring back about 1985 that had three
channels plus ground, two of which pulsed at different rates. One
for a LED and the other for a sonalert. Very low RPM obviously, but
it worked! Used copper coated PCB board and slot car brushes. Which
were kind of hard to find in the mid 80s. Slot cars had been out of
fashion for over a decade and no internet to just 'look things up'.
http://alt-config.net/slipring.jpeg

Um, the LED was in the bats mouth;-)

Hah! Well, that explains things, Mr. BSC.

--
Newman's First Law:
It is useless to put on your brakes when you're upside down.
--Paul Newman