This circuit is from Electronics Now magazine, February 1987. The number of channels is high depending only on the distances of the stations and the losses in the cables.
This circuit is from a Popular Electronics from the 80's. The components used are not common...
This circuit for 6 lamps was found in old American documentation. The supply is of high voltage...
The circuit is from the 1994 National Semiconductor Linear Applications Handbook but can be...