[TenTec] Looking for keyer (?) schematics

Tue Apr 2 06:06:57 EDT 2019

Folks,
I have three boards with no clues of origin or schematics.
Two of them have a reed relay, 8 transistors, 3x 7400, 1x 7410 and 1x
7476, coded 90461.
The third one has 9 transistors and one UA747, coded 90406
I also got a couple of KR50 mechanisms, so it will be nice to know how
to drive the magnets to adjust the force.
Any hints welcome!
jon, ea2sn / ae2sn