| 摘要 |
<p>1. Reliable railway-track-"clear" signalling device for monitoring a section of track, with a transmitter which has a resonant circuit incorporated in blocking oscillator circuitry with regenerative feedback, and with adjoining sections of track activated by different frequencies, and with track section receivers assembled similarly to the transmitters for receiving the modulated signals via frequency-selective filters, characterized in that the blocking oscillator circuits (V17, UE8, UE9, and V7, UE1, UE2 respectively) are each fed at their transmitting and receiving sides via a diode bridge circuit (V12 to V15, and V1 to V4, respectively) and a first ceramic plate condenser (C4 or C1) with two diagonally arranged terminals on each plate covering, whereby an additional transformer (V18) is coupled to the outlet side on the case of the regenerative feedback transmitter (UE10) with each transmitter and this takes effect on an output transformer (UE11/UE12) via which teh operating voltage of the transformer (V18) is also supplied whereas the regenerative feedback transmitter (UE3) of each receiver directly feeds its output transformer (UE4/UE5) in a preferred embodiment of the invention, and that the interposed frequency-selective filter comprises a further transmitter (UE14/UE15) with a safety resistor (R13), a second ceramic condenser (C6) with two diagonally arranged terminals on each plate covering and a frequency throttle (FD).</p> |
