GB1433008A - Control units for electronic communications devices - Google Patents

Abstract

1433008 Pulse button receiver control WALTER PREH GmbH 26 Nov 1973 [24 Nov 1972] 54819/73 Heading H3Q [Also in Division H1] In a control unit for an electronic communications device having mutually cancelling pushbutton switches 11 for changing channels of the device, at least one support 5 carries a plurality of variable resistors (not shown) and rotary controls 33 for these variable resistors and the support 5 is slidably mounted so as to be withdrawable independently of the push-button switches to facilitate manual rotation of the rotary controls 33. Also the variable resistors are electrically independent of the push-button switches 11 such that when the control unit is controlled and in use the rotary controls 33 can be used for varying signals which will affect operation of the device independently of whichever of the push-button switches is operational. As shown in Fig. 1 a plastics plate 2 is mounted on a plastics body 1 by resilient tongues 3. Two slide-in frames 5 can be withdrawn so as to allow adjustment of knurled knobs 33 which are connected by round shafts 34 having flats which pass through plastics sleeves associated with the siders of rheostats accommodated circular recesses 29, Fig. 3, formed at the top and bottom of the plate 2. The knobs 33 may have graduated scales. A plastics frame (19, Fig. 4, not shown) is spring biased by a spring (22) and co-operates with each switch rod 13, Fig. 3, connected to each button 11 so that the buttons 11 are mutually cancelling. A pair of contact springs 16 are fitted to each switch rod 13 so as to contact electrical connectors on the base plate 2 when the associated button 11 is pressed. When a button 11 is pressed it also operates to close the mains switch 32 which is switched off by pressing mains switch 12. The control unit may be used in a television receiver to select preset reception frequencies by the push button switches. The rotary control members 33 may be used to adjust picture contrast and brightness and sound tone and volume.