Designs Department - Monitoring & Control Section

Automatic Monitor Minor

In order to reduce costs it was necessary to make transmitting stations run without staff being in attendance.  To make this development possible, automatic equipment had to be devised to monitor the performance of the equipment and lines.  The Automatic Monitor Minor was among the earliest projects undertaken in 1947 by the newly formed Department.  HBR, FAP and CG designed apparatus, for use over short links, which gave an alarm if the signal-to-noise ratio or programme level deviated significantly from pre-determined values. 

Automatic Monitor Major

In 1952, the first Automatic Monitor Major, for use over long links, was installed at the Start Point transmitter.  In this monitor, the signal with which the programme signal was compared was transmitted in coded form on a 7 kHz – 8 kHz carrier, over the programme circuit. 

Fault Reporter

At the Oxford unattended transmitting station, commercially produced fault reporting equipment was installed experimentally, after suitable modification by Designs Department in 1964.  This equipment initiated a telephone call to the Regional Centre at Sutton Coldfield in the event of a fault occurring at the station, the existence of a fault being indicated in plain speech reproduced from a disk recording. 

Universal Switching System

Where the Post Office introduced carrier programme circuits, the use of phantom circuits for signalling was not possible.  To overcome this problem a Universal Switching system was designed using very robust pulse code signalling.  The system could be used on speech or music circuits without interfering with the normal traffic.  The first application in 1969 was between London and Wrotham to enable various transmitter functions to be controlled from Broadcasting House.