[GreenKeys] Constant Current Loop

[WB6BLV]

For a long time I have experimented once in a while with constant current
loops for my TTY equipment.  Long ago Irv Hoff gave a presentation at WA6YKY
(Northrop Institute of Technology, Inglewood, Ca) that included information
of holding the current constant in a loop as various combinations of
machines were patched in and out.  Back then we used a 6V6 with a 1K
wirewound in the cathode as a means of making the current pretty much
independent of the number of selector magnets in the loop.  I have been
using a solid state desing on and off for several decades.  If you have any
interest in a copy of the schematic, including nominal component values for
20 and 60 mil loops (GIF or JPG format), please contact me off-list.

73

John
WB6BLV at inreach.com