Radio and Electronic Engineer

Earlier this year, after effecting a change in the terms of reference and funding of the British Productivity Council, the Government decided to discontinue the Grant-in-Aid to the National Council for Quality and Reliability. The following appraisal of the work of N.C.Q.R. during its ten years and some thoughts on its future role has been contributed by the Institution's representative on N.C.Q.R... View full abstract»

The well-established Doughnut and Cloverleaf wave buoys developed by N.I.O. are described briefly and details of a disposable wave buoy, at present under development, are given. Because of certain operational difficulties experienced with the Doughnut buoys, a digital telemetry system has been developed and this is described in full detail. The system allows for simultaneous sampling of up to 10 a... View full abstract»

A stepper motor has the ability to translate digital signals into angular shaft positions. This paper deals with the dynamic characteristics of a 90° permanent magnet motor, when used to switch a load through a sequence of angular steps. The non-linear system equations are derived, and linearized versions of these equations are used to estimate the dynamic response for single-step operation. Mult... View full abstract»

The paper describes the measuring techniques associated with complete u.h.f. transmitter installations, indicating the large range of test equipment that is required. An indication of the considerable distortions produced by a klystron amplifier is given, but no attempt is made to detail the mechanisms involved. View full abstract»

The mode of operation of the phase-locked loop is briefly described, an analytical note being given in an Appendix. Communication applications are the tracking receiver, f.m. detection, the phase-locked homodyne and f.s.k. detection. Instrumentation applications are phase modulation, pulse-width modulation, phase-locked servo for magnetic recording and a phase-locked frequency standard. The voltag... View full abstract»

Discusses h.f. communication problems and the stringent and often conflicting requirements placed on the performance of any h.f. communication receiver. The H2900 receiver has been designed with these requirements in mind. The receiver uses a novel method of digital frequency synthesis allowing for small frequency increments of 1 Hz. View full abstract»

This paper surveys the problem of matching colour television monitors and the relative merits of optical or electronic aids. An optical design for assessing the normalizing white of a colour monitor is then discussed at length, and comments are made in detail on the alternative solutions at each stage of the design. It is concluded that a Lummer-Brodhun matching field, together with a tungsten lam... View full abstract»