| 摘要 |
PCT No. PCT/FR81/00042 Sec. 371 Date Nov. 16, 1981 Sec. 102(e) Date Nov. 16, 1981 PCT Filed Mar. 24, 1981 PCT Pub. No. WO81/02714 PCT Pub. Date Oct. 1, 1981.An improvement in apparatus for the secure transmission of information through rails in zones of propagation independent from the sections of the track block-section system embodying the use of series resonant circuits tuned to the information carrier frequency and connected between the rails at the end of a transmission zone and comprising two identical series resonant circuits disposed in parallel and each comprising a capacitor in series with the primary winding of a transformer, with the secondary windings of the two transformers being connected in series and in opposition, so that an oscillating signal appears at the terminals of the circuit thus formed in the case of failure of one of the resonant circuits. |
