GB474923A - Improvements in tuning indicators for multi-range wireless receivers - Google Patents

Abstract

474,923. Adjusting wireless apparatus. GILLARD, F. G. May 14, 1936, No. 13701. [Class 37] In a multi-wave-band radio receiver wherein the tuning setting is indicated by a cursor 21, Fig. 1, driven by an endless belt 9 associated with the tuning spindle 1, a lamp 21a on the cursor projects a light beam through one of a plurality of apertures 22, 23, 24 in the cursor on to a corresponding wave-band scale behind which the cursor moves, a shutter 26 slidable in the cursor and operated from the wave change switch masking those apertures pertaining to the inoperative wave bands. The hollow tuning spindle 1, Fig. 1, adjusts the condenser 4 through pinion 6 and quadrant 7, fine adjustment being effected in known manner, for example, by a spindle 50 and ball clutch inside spindle 1. A scale 50a on spindle 1 may be provided to indicate movement of spindle 50 relative thereto. The cursor is slidable along a bar 20 and the driving belt 9, anchored at 10 to a sleeve 8 on the spindle 1, passes over guide pulleys 12, 13, 15, 14, and pulleys 57 on the cursor carrier 19 to a tensioning spring 17. The shutter, having a single aperture 25, is biassed to its lowest position by a spring 43 and at 32 is anchored to a cord 31 passing over a pulley 33 on the carrier 19, over fixed pulleys 34, 35, adjustable pulleys 36, 37, Fig. 3, and over fixed pulleys 38, 39, to an anchorage 40 on the carrier. The wave range switch is adapted to rock a spindle 30 and with it a crank 42 carrying the pulley 37, to any of the three positions shown in Fig. 1, whereby the cord 31 is tensioned or slackened to register the aperture 25 in the shutter 26, with the appropriate aperture 22, 23 or 24 in the cursor. For adjustment of the cord 31 the pulley 37 is adjustably mounted in the crank 42, Fig. 3, and the pulley 36 is mounted on a member 60 rotatably adjustable about a screw 6 and secured in adjusted position by screws 61, 62. In a modification, the cords 9, 31 are replaced by a single cord, which is secured at one end to the lug 32 of the shutter 26 and passes over pulleys to the sleeve 8 where it is anchored. Specification 402,797 is referred to.