Hi Ken,

I don't see any real reason to encrypt the messages source because the transmissions is within sight and not broadcast. If they wanted encryption, then I would suggest the 4 rotor Enigma. I don't believe the US gave the Russians or the Chinese the US manufactured Bombe by the National Cash Register Company during the latter part of WWII.

Regards,
Don_

"A man's got to know his limitations..."
Harry Callahan, SFPD