GB497951A - Improvements in or relating to multi-scale indicators more especially for multi-wave band radio receivers - Google Patents

Abstract

497,951. Adjusting wireless apparatus; indicating-apparatus. MARCONI'S WIRELESS TELEGRAPH CO., Ltd. June 30, 1937, No. 18213. Convention date, June 30, 1936. [Class 37] [Also in Group XIX] A multi-scale indicator, particularly for indicating the tuning of a multi wave-band radio receiver, comprises a plurality of parallel slat like translucent scale bearing members joined edge to edge with the interposition of opaque layers, and means for selectively illuminating the members by edge lighting. Figs. 1, 2 show translucent scale bearing slat like members 22, 24, 26 joined edge to edge by opaque strips 23, 25 and mounted in a frame 16 slotted at 16a, 16b, 16c adjacent the ends of the slats so that the slats may be illuminated by light from lamps 50, 52 and reflectors 51, 53 entering the slats edgewise through the slots 16a..... The lamps 50, 52 are carried on arms 46, 48 and the slat illuminated is selected by rotating the knob 62 controlling the wave range switch 64, a pinion 61 on the shaft 60, controlling the wave range switch, rocking the arms 46, 48 through gear 41 and shaft 40 so that the lamps line up with the appropriate slots 16a, 16b, 16c, exact positioning thereof being determined by a detent device coacting with shaft 60. Alternatively, the lamps may be fixed adjacent the ends of the central slat 24 and provided with quartz rods for conveying light therefrom to points immediately adjacent the ends of the other slats, the slat illuminated being selected by slotted shutter elements disposed between the lamps and the ends of the slats and rocked to operative position in a manner similar to that of the lamps in Figs. 1, 2. In another embodiment a lamp is provided adjacent each end of each of the slats, the pairs of lamps being selectively illuminated by a switch operated with the wave range switch. The tuning pointer 70 is driven by any known means, for example by an endless cord 72 operated from a pulley 78 on the tuning shaft 79. The pointer is bent to conform to the contour of the dial formed by the slats which may be plane, part cylindrical or, as shown, part polygonal. Alternatively, a shadow type pointer wherein light is projected through a narrow slit in a mask moved rectilinearly behind the slats, may be used. Specifications 11112/09, [Class 3 (ii)], and 438,010 are referred to.