GB362001A - Remote control device for radio receiving sets - Google Patents

Abstract

362,001. Wireless receiving apparatus. KOLSTER-BRANDES, Ltd., Cray Works, Sidcup, Kent.-(Assignees of Clement, L.M. ; 42, Pollard Road, Mountain Lakes, New Jersey, U.S.A.) Sept. 4, 1930, No. 26430. Convention date, Oct. 16, 1929. [Class 40 (v).] Relates to means for controlling the tuning of a wireless receiver, either by means of switches mounted on a remote-control panel which may be located on the arm of a chair or at any other convenient point, or by means of similar switches arranged on the receiver itself. According to the invention, a commutator-switch is mounted on the motor-driven shaft of the main tuning-control and is arranged to open the driving circuit at one or more pre-selected settings. Volume control is effected by regulating the voltage on the screening- grid of the amplifier valve, either at the set or remotely ; whilst flash-lamps indicate on the set and on the remote-control panel (a) when the set is energized, and (b) the period during which tuning is taking place. The loud-speaker is shortcircuited during the operation of tuning. The complete equipment is shown in Fig. 1 comprising the receiver A, rectifier C, low-frequency amplifier B, moving-coil sneaker D, motor-unit F, relay unit G, all in more or less close association with the receiving set, and a distant-control panel E. A gramophone pick-up may be inserted across the terminals 45. When a selected button-switch 56 on the remote-control panel is pressed, the motor 30 also shown in Fig. 2, rotates a split-ring commutator 27 which is mounted on the tuning-condenser. shaft until the corresponding contact 28 mounted on a fixed plate 80 comes against the insulation gap, thereby breaking the motor circuit and leaving the tuning-condensers set to the required broadcast transmission. The drive from the motor is transmitted through gears 66, 67, Fig. 2, to a shaft 68, which is coupled to the tuning-condenser spindle through a belt 79. This drive is only effective so long as a pin-wheel 69, splined to the shaft 68, is in gear with the wheel 67, a connection which is maintained by the action of a pivoted armature 71 and a relay coil 34. When the coil 34 is de-energized, a spring 70 disengages the gears 67, 69 so that the tuning-condenser can be manually controlled from a knob on the receiverpanel. The pre-selector contacts 28, shown separately in Fig. 5, are initially adjusted to the correct position on the plate 80, and are then screwed firmly in place. The motor 30 rotates in the forward or reverse direction according as the fieldwinding 31 or 32 is energized. The panel G includes a start relay 50 for energizing the set, a stop relay 51, a volume-control relay 52 for the remote-control panel, and a similar relay 53 for the receiver cabinet, together with a relay 54 for short-circuiting the loud-speaker during tuning- operations. A similar series of press-buttons to those shown at 56 on the remote-control panel are mounted on the receiver-panel. for direct preselection control of the set.