GB1069216A - Pricing apparatus for subscription television - Google Patents

Abstract

1,069,216. Subscription television systems. BRITISH TELEMETER HOME VIEWING Ltd. Dec. 23, 1964, No. 52374/64. Heading G4V. In a subscription television system, the price charged for a programme is indicated at the receiver by means responsive to the frequency of a single transmitted signal. In the Figure, a motor 34, when energized, drives an endless band 40, so that projection 40a and 40b thereon, alternately engage a finger 46 on slider 48. A further finger 56 engages a spring-biased pawl 58 on slider 66, so that the motor traverses both slides from right to left. At the position where abutment 76 closes switch 80, projection 40a or 40b disengages from finger 46 whereupon spring 70 returns both sliders to the extreme right. This cycle is repeated, until a price indicating signal is applied to detector 28 from a subcarrier. The detector contains a tone generator the frequency of which is swept through the relevant range, e.g. a sonic or ultrasonic range, by the shaft of gear 52 meshing with rack 50. When the local tone frequency matches the fiequency of the " price " signal, the detector output energizes solenoid 88 to apply brake 90 and stop the motor. A finger 72 indicates the price on scale 74. The insertion of coinage closes switch 93 a proportionate number of times, to operate stepping pawl 95 on rack 96 and advance slider 66. Pawl 58 is thus freed from finger 56, and engages non-return rack 62. When the inserted coinage corresponds to the price demanded, finger 72 reaches the " paid " position PD, and switch 80 is closed to enable the programme to be received. When the price signal ceases, solenoid 88 is de-energized, and slider 48 is moved to the left, finger 56 releasing pawl 58 from rack 62, and the two sliders are again swept from right to left by motor 34 until the next programme price signal is received. In an alternative, slider 48 is reciprocable manually, and the coincidence of the local tone and received tone frequency is shown by lighting a lamp, and energization of a non-return pawl which retains slider 66 at the correct indicated price, while permitting its advancement by the coin mechanism.