GB1215940A - Method and means for screening and de-coupling electronic circuits - Google Patents

Abstract

1,215,940. Electric component assemblies. COMITATO NAZIONALE PER L'ENERGIA NUCLEARE. 30 Nov., 1967 [1 Dec., 1966], No. 64515/67. Heading H1R. Relates to an arrangement for shielding and decoupling electronic circuit assemblies operating at high frequencies e.g. 408 Mc/s. In an amplifier embodiment described a resonant circuit 8 (Fig. 2b) of an input filter and resonant circuits 9, 10 of an output filter respectively including wire loops 81, 9<SP>1</SP>, 10<SP>1</SP> tuned by capacitors 8<SP>11</SP>, 9<SP>11</SP>, 10<SP>11</SP>, are mounted on a base-plate 11 within two parallel channels formed by a member 13 (Fig. 2a) and a common wall 22, joined to the plate 11, a slot in the wall 22 straddling a metal plate 23 on the base-plate as shown in Fig. 3. The channels function as waveguides for interference frequencies. Shield plates 24, 25 are attached one to each face of the wall 22, to prevent coupling between lead wires of active components. For instance, the end of a “ wave coaxial line 29 which is connected to a transistor base electrode (15) (Fig. 1, not shown) is located in a hole 27 in the block 23 mid way between the two shields while the end of a “ wave coaxial line 28 connected to the emitter of a second transistor is located in a hole 26 outside the shields toward the input stage. Holes are also provided in the block 23 to receive the transistors and resistors. A coaxial input signal lead 37 is fastened to the block and connected to the input resonant circuit 8.