| 摘要 |
<p>(Case No. 7009) A cross field transformer circuit arrangement for use as a solid-state, synchronous detector track relay device for alternating current track circuits. The track signal at the receiver end is applied to the primary winding on the main magnetic circuit and the local input signal to another primary winding on the modulating magnetic circuit of the saturable core of the transformer. Each input is transformer isolated from its source and passed through a noise-rejecting filter tuned to track circuit frequency. The main magnetic circuit flux is modulated by the modulating magnetic circuit cross field flux so that the secondary winding, on the main magnetic circuit, produces an output signal at double the track frequency, i. e., its second harmonic. A band pass output filter passes only this second harmonic signal to a full-wave rectifier to energize a biased track relay only when both inputs, in phase and of the same frequency, are received. For track circuit use, a diode added in series with the local input filter and a second diode inserted in series with the secondary output modify circuit operation to inhibit response by a two-winding, biased track relay to an opposite polarity track input signal received through a failed insulated joint.</p> |
