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Robert Gift

former OL presenter
Saw a glass-encasedevice whichad a horizontal "wheel" made of thin metal disks, about 3-1/2 inches in diameter.
Beneath it is a copper-colored spring.
The assembly somewhat resembles a timepiece balance wheel.

On top is a thick horizontal coil.
Made by GRS.


Active Member
A relays that transmits code. Haha, but really that is what it is. It transmits the code rate either on the rail or over line wire to the next signal. Typical codes are 75 Hz, 120 Hz, 180 Hz. So there are code relays that produce those code rates and that relay transmits the codes.

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