GB1467790A - Coupling arrangement for the relay of video signals - Google Patents

Abstract

1467790 Video signal cross-bar switch LICENTIA PATENT VERWALTUNGS GmbH 18 Feb 1975 [19 Feb 1974] 6840/75 Heading H4R Coupling arrangement for the interconnection of video transmitter and receivers uses a cross-bar type switch with the transmitters S1 and receivers E1 connected to respective longitudinal bars s1 and e1 which can be interconnected via pairs of switching elements X and cross-bars vs1 and ve1, in which the longitudinal bars and the cross-bars are formed as strip lines the characteristic impedance of which match the characteristic impedance of the subscriber lines. As shown in Fig. 2 the longitudinal bars s1 to Sn, e1 to en, are individually formed as strip lines 21 on a panel 10, the line having an appropriate impedance, when considered relative the backing earth plate 50. Screened tuned reed relays are mounted on the panel, at X, to interconnect the line 21 with selected ones of the strip conductors 31, 32 &c. and the panel is mounted on a connector panel Bs or Be, Fig. 3, with plug pins 61 to 6k engaging sockets carried by the connector panel, to connect the strip conductor 31 to 3i to strip lines forming cross-bars vS1 to vSi, or ve1 to vei. Screening conductors are provided on panels A, Bs, and Be between the strip conductors and cross-bar strip lines to reduce cross-talk. A number of panels Bs and Be can be connected in parallel to increase the capacity of the system. Cross over switches K1 to Kn are provided to connect subscriber go and return lines S1-n and E1-n to the longitudinal bars s1 to sn and e 1 to en respectively when the subscriber is the calling party and change over the connection, so that Si to Sn is connected to e1 to en and E1 to En connected to s1 to sn. when the subscriber is the called party.