Abstract: A method and a configuration for the operation of a railroad line include at least one signal box for providing line-block-section-specific light signal data and a line side system for an intermittent automatic or inductive train control system at line block section ends. In order to dispense with line side light signals and still be able to continue to use a signal box logic concept for light signals, the signal box transfers the line-block-section-specific light signal data over a radio system to a rail vehicle and the intermittent automatic or inductive train control system transfers line-block-section-specific data to the rail vehicle during passage by the rail vehicle. The rail vehicle determines the light signal data assigned to the line block section by comparison of line block section specifics.

Abstract: An electronic code following relay for use in a railroad signaling system includes a timing circuit for receiving an input square wave signal coded at a pre-determined code rate, and regenerating the input square wave signal at the pre-determined code rate after a predetermined time delay; and a driving circuit coupled to the timing circuit for receiving the delayed square wave signal therefrom and conducting, at the predetermined code rate, at least a power source to at least one of various components in the railroad signaling system including a rail of a track. The electronic code following relay is preferably microprocessor-based and uses an opto-coupler and various solid-state relays for conducting various DC and AC power sources to the components of the railroad signaling system.

Abstract: An electronic code transmitter is disclosed for driving a number of code following relays of a railroad signaling system. The electronic code transmitter comprises a timing circuit and a driving circuit. The timing circuit generates, at a predetermined code rate, square wave pulses with an approximate 50/50 duty cycle. The driving circuit receives the square wave pulses and conducts, at the predetermined code rate, a power source to the code following relays. Where the timing circuit is a timer IC operating in an astable oscillator mode, the timer IC receives an isolated DC power from a DC-DC converter. A resistor is coupled in parallel with the code following relays if the code following relays present a sufficiently high impedance load to the electronic code transmitter. Thereby, the electronic code transmitter is capable to drive code following relays of any load impedance.

Abstract: A transmitter for transmitting cab signal and track signal currents to a pair of rails includes the circuitry for mitigating runby currents which are not fully shunted by the rail vehicle. High runby currents at the leaving end of a block are reduced by sensing the presence of a railway vehicle in the leaving end of the block. In response to sensing the rail vehicle the cab signal voltage is reduced to a lower level. The lower level and the position at which the railway vehicle is sensed are adjusted so as to permit a lead vehicle to receive at least a minimum cab signal value throughout its journey while assuring that following trains receive less than the minimum cab value required to activate the vehicle based receiver. The train is sensed by the voltage drop across the rails as the train approaches. A relay is used to respond to the presence of the train by applying a lower cab signal to the rails.