GB650912A - Improvements in or relating to electrical units for radio receivers and the like - Google Patents

Abstract

650,912. Printed circuits. ELECTRIC & MUSICAL INDUSTRIES, Ltd. Aug. 19, 1948, No. 21894. [Class 36] [Also in Group XL (c)] An electrical unit comprises a plurality of insulating wafers secured one above the other in stack formation and having at least one electrical component formed by an adherent coating on one of said wafers and at least another electrical component formed by an adherent coating on another of said wafers, means being provided for conductively connecting said components. A wafer is defined as a sheet which is sufficiently thin to be flexible. As shown in Figs. 2 and 3, two similar wafers of insulating material 5 and 6 are provided, and the top surface of wafer 5 has applied to it by printing or like means two coatings 8, 9 of high conductivity which cooperate with a coating 12 on the reverse side to form the condensers 1, 2, Fig. 1. The coatings 8, 9 are connected by a coating 11 of resistive material forming resistor 3, resistor 4 consisting of a coating 20 on the insulating wafer 6, and the two wafers are assembled so that the surfaces 7, 19 are on the outside, and are secured together by metal eyelets 25 ... 28, which also secure flexible leads and soldering tags and connect the components as by a piece of metal foil 33 placed between the wafers to make contact with the coating 12 and folded over and clamped by the eyelet 27 to make contact with the resistive strip 20. An alternative arrangement, Figs. 4 to 7 (not shown), provides two resistors having a common terminal point and two further resistors and one condenser of larger capacity having a common terminal point.