Electronic code follower relay

An electronic code following relay for conducting at least one of coded DC and AC currents to various components in a railroad signaling system, the electronic code following relay comprising:

• a controlling relay having an input connectable to a coding power source of the railroad signaling system to receive therefrom a square wave signal coded at a predetermined code rate and duty cycle, replicate the input square wave signal and output the replicated input square wave signal;
• a microprocessor integrated circuit coupled to an output of said controlling relay for receiving the replicated square wave signal, said microprocessor integrated circuit comprising at least first and second microprocessor-programmed time delay regulator circuits for delaying the square wave signal with at least first and second different predetermined time delays, respectively;
• an opto-coupler integrated circuit having at least first and second control inputs coupled to said first and second time delay regulator circuits, respectively, of said microprocessor integrated circuit, and at least first and second independently operated outputs controlled by said first and second time delay regulator circuits via said first and second control inputs, respectively, of said opto-coupler integrated circuit;
• at least a first solid-state relay coupled to the first output of said opto-coupler integrated circuit, for receiving the square wave signal delayed with the first time delay and conducting, at the predetermined code rate, at least a first power source to certain components in the railroad signaling system;
• at least a second solid-state relay coupled to the second output of said opto-coupler integrated circuit, for receiving the square wave signal delayed with the second time delay and conducting, at the predetermined code rate, at least a second, different power source to certain components in the railroad signaling system;
• and
• a dedicated DC power source coupled to at least said microprocessor integrated circuit for providing an isolated DC power source to the microprocessor integrated circuit.

In combination,

• an electronic coding power source for generating, at a predetermined code rate, a square wave signal with a predetermined duty cycle;
• and
• an electronic code following relay comprising
• a timing circuit for receiving the square wave signal as an input thereof and delaying the input square wave signal at an output thereof with a predetermined time delay;
• and
• a driving circuit coupled to said timing circuit for receiving the delayed square wave signal therefrom and conducting, at the predetermined code rate, at least a power source to various component of a railroad signaling system.