BBCeng.info
Recollections of BBC engineering from 1922 to 1997 |
The British Broadcasting Corporation web site is: www.bbc.co.uk |
Designs Department - Reminiscences |
||
I joined Design Department in the first week of December 1948 from the Ottringham Transmitter Station OSE5. At that time Designs Department had only been in existence for about a year. Since it had been formed by bringing units from other departments the various sections were located in several buildings in central London. The head of the department was H B Rantzen who had previously been Head of Lines Department. When I joined he was on a secondment to the United Nations in New York organising their world-wide communications network so his assistant DR A R A Rendall, who had joined the BBC from STC (Standard Telephones and Cable), was running the department. The Head of Designs Department’s office was on the second floor of Brock House which is close to Broadcasting House. Also in Brock House were the Television apparatus Section under Tom Worswick, the Sound Apparatus Section under H D Ellis, Lines Section under FS, RF Section under F A Peachey, a small drawing office and a stores. On the ground floor of Broadcasting House was Television Transmission Section under Neville Watson. A part of the Service Section under Charlie Field was located in the basement of Bentinck House in Bulsolver Street, which is two streets away from Broadcasting House. The rest of the department, was the Recording Section under Henry Davis and this was at the Maida Vale Studios. All the sections of the department had numbers which were as follows:- Section 1 – Recording, Section 2 – Lines, Section 3 – Sound Apparatus, Section 4 – Services, Section 5 – RF, Section 6 – Television Transmission, Section 8 – Television Apparatus. For some unknown reason there was, at that time, no Section 7. Having presented myself at H.D.D. ‘s office on the second floor of Brock House I was sent across to Broadcasting House to room G26, which was Neville Watson’s office. There I was introduced to the members of his section. This consisted of two senior engineers, Stuart Padel and Lenny Holt and engineers Walter Anderson, Ken Quinton and John Shelley. Dennis Packham was the laboratory technician. My position was that of a supernumerary replacement pool engineer grade C – and I was expected to obtain a permanent post within two years; a daunting prospect as at that time a large number of engineers were being made redundant following the Olympic Games in the August of 1948. Our desks were crammed into rooms G. 26 and G.27. Further along the corridor was a large room, G.28, which was the BH Switching Centre and next door to that was the section’s laboratory. The work of the section fell into two parts. One was the liaison with the Post Office in handling the routing of Television Outside Broadcasts to the transmitter at Alexander Palace, and the other was the design and manufacture of the specialised transmission test equipment for use with television transmission systems, both over cable and over the air. The programme signal transmission work carried out in liaison with the Post Office was located in G.28, the Switching Centre. Here there was a balanced pair cable connecting it to Alexander Palace which at that time was the one and only television transmitter. This cable had been installed before the war to connect various Outside Broadcast (OB) locations in central London to Alexander Palace. The first use of this cable was to carry signals from the Mall at the Coronation of 1936 to Alexandra Palace. A cable also connected the Switching Centre to Wembley stadium from which regular ice hockey matches were televised. In the case of OB’s from theatres these were connected to Broadcasting House via ordinary telephone lines. This transmission work involved co-operating with the Post Office engineers in equalising the link between the OB site and the switching centre so that it was capable of transmitting the 3 MHz bandwidth needed for the 405-line television signal, so that a reasonable picture would result. When I joined the department I worked with Lenny Holt on the development of test and transmission equipment as well as assisting with the acceptance testing of OB links coming into the Switching Centre. One piece of equipment we were working on was a waveform monitor which was a specialised oscilloscope to enable the television wave form to be accurately measured and assessed. It also had a strobe facility so that any line of the picture could be picked out and examined. Another piece of equipment was called the clamp which was used to remove mains pick up from the signal so that the receiver time bases were not disturbed. I also worked on the design of a video distribution amplifier which was used to provide a number of separate outputs usually four from one input. Another piece of equipment we were developing was a television test generator to produce the special signals for testing the links carrying the television signals to the transmitters as well as checking the performance of the transmitters which would be constructed. This design work was constantly being interrupted by having to carry out testing work on the transmission links. In those days television was only transmitted in the evenings, usually from about 20.00 to 22.30 and when there was an OB we took turns to man the Switching centre during the transmission. On Saturdays there was often an ice hockey match from Wembley and the overseeing of these events used to fall to those of us who lived in London. While the television transmission section was working on the handling of television signals the television apparatus section was looking into the improvement and development of television cameras. At that time the main camera tubes were the image orthicon and the emitron. The main problems were to improve sensitivity to reduce studio light levels and to get better geometry of the pictures. Development had also started on developing production facilities such as Inlay and Overlay. Inlay was a method of making a composite picture from two others with the viewer being unable to see the join. Overlay was the same technique but involved live artists and was a much more difficult technique to use. Thought was also being given to methods to enable remote picture sources to be mixed with studio pictures without a frame roll occurring. Outside broadcasts of television also came within the orbit of this section. The sound apparatus section was working on the design and development of sound control desks and all the ancillary equipment used with them, such as limiters, and various amplifiers. In those days all this equipment was designed and manufactured in the BBC. The RF Section was at that time looking at the problem of automatically monitoring the output of radio transmitters as well as the design of monitoring receivers for sound. Over at Maida Vale the Sound Recording Section worked on the development of high quality players for records for use in BBC studios. The use of magnetic tape was also being investigated. At this time the major interest and drive was on television as this was believed to be the next big step forward. Although the number of television receivers grew quite slowly the policy was to press ahead as it was felt that the situation would change. This change occurred in 1953 with the Coronation which caused television to take off. During 1949 the plan to take television to the regions was started and the first part was to take television to Birmingham. A transmitter was built at Sutton Coldfield near Birmingham and connected to the BBC premises in Broad Street by a co-axial cable. The Post Office built a radio link from London to Birmingham to carry the signals. The London end of this link was the Museum Telephone Exchange which is the building still at the base of the BT Tower. On the roof of the Exchange were two large mesh dishes, one go and the other return. The link operated at a frequency less than 1000 MHz. I was involved with Lenny Holt and others in the extensive testing which had to be done on both the go and return links before they could be used for programmes. These tests used the equipment we had designed and built in our workshop and enabled the BBC to ensure that the highest quality television pictures were received in Birmingham. This work occupied most of the section for the second half of 1949. Since the feed to the transmitter passed through the Birmingham Switching Centre on a connecting cord, which could be easily removed a number of us junior engineers worked a rota for manning the centre during transmission times. Two other engineers in the section, Walter Anderson and Ken Quinton were working on VHF and microwave links which were very new in the BBC although I, as well as some others had worked on and designed equipment using these frequencies since 1943. I, together with other engineers, was involved in the testing of the links between Birmingham and Manchester during 1951 as the Holme Moss transmitter came into service in October 1951. The next step was the testing of the link between Manchester and Kirk O’Shotts. This link was entirely microwave and posed special problems but the transmitter was in service in March 1952. After this we then tested the link to Wenvoe which opened in August 1952. In the Autumn of 1952 I left the Television Transmission Section and joined the Television apparatus Section under Tom Worswick, which was situated on the second floor of Brock House. I filled the grade B1 engineer vacancy created when Mike Spooner left to go to Rediffusion to work on flight simulators. The other engineers in the section were John Bliss, Brian Shone and Geoff Larkby. The laboratory technicians were Jimmy Moon and F W Nicholls. In the job I took over the work Mike Spooner was doing which concerned special effects in television production. These effects were known as inlay and overlay. Inlay was the facility which allowed a producer to take parts out of one picture and put it into another without the join being seen. It also allowed a producer to wipe between two pictures. Overlay was a similar process except that it allowed a live artist to be put into a picture and move as though he was actually there. This in 1952 was the forerunner of the technique now used extensively in television, the weather forecast being the prime example of its use. Another project I was in was the design and building of equipment for the recording of the Coronation ceremony in 1953. I designed and built a high quality television display monitor. The picture on this monitor was then filmed by a 16 mm camera to record the event. Another application for this monitor was in an optical standards converter when the monitor was placed on a special bench with a television camera operating on a different standard. In the first equipment, the monitor operated on 625 lines and the camera on 405 lines to enable pictures from the continent to be converted for use in BBC programmes. During this time transistors were being improved and were beginning to look promising for use in television equipment. This was important because the heat generated by equipment in television control and apparatus rooms was becoming a problem and this could be reduced by a factor of 20 if transistors could replace valves, I began work on devising ways to use them. In the Autumn of 1953 I was given the task of reading the reports of the NTSC (National Television Standards Committee) which had been working in the USA to devise a system for transmitting colour television after the fiasco generated by the two systems, one proposed by RCA and the other by CBS, had ensured that colour television had not taken off. I then started the work of building coding, decoding and display equipment to produce NTSC signals on 405 lines so that the BBC could gain experience of handling colour signals. Marconi, at their research department at Great Baddow were also working on this task. As a result of discussion at high level with Marconi I joined them in January 1954 for 6 months to help in the design, production and testing of a complete range of colour television equipment working on 405 lines. The object of this work was to stage a demonstration of colour television for showing to the press and government of the day as well as the BBC. The equipment consisted of a slide and film scanner, a colour bar generator for producing a known test pattern, a three tube camera using image orthicon tubes and a two tube camera. Having got all this working at Great Baddow it was moved to Marconi House on the Strand during late Spring 1954 for a series of demonstrations to organisations and people of influence. The actual demonstrations took place in May and June of 1954. Following these demonstrations it was decided that the next step should be a series of tests over the entire television network including the transmitters. To do this the equipment was moved during July 1954 to the 6th floor of Western House to an area at the northern end of the Great Portland Street side. This site was chosen because there was a high quality cable link to the Switching Centre in Broadcasting House which then gave access to the entire transmission chain. During the Autumn of 1954, following the end of the evening transmission at about 22.00 tests were carried out on the transmission network. Colour pictures were radiated by Alexandra Palace and picked up in Western House where the signals could be measured and the picture quality assessed. The pictures received were of variable quality particularly as regards colour fidelity where flesh tones often varied with the picture content. This had been anticipated and thought had been given as to how it could be overcome. The weakness of the American NTSC system which we had modified to fit into our 405 lines system was that the colour rendition was dependent on a particular property of the transmission chain which had virtually no effect on black and white pictures. This property, known as differential phase distortion, caused the colour to change with the amplitude of the signal and was most noticeable on flesh tones. Although faces have very little colour everyone feels that they know what colour a face should be and over some transmission links a person’s face colour would change as other parts of the scene changed, and often tended to display symptoms of sea-sickness. During the Autumn of 1954 colour pictures mainly from slides or film were transmitted over the network as far as Kirk O’Shotts and Wenvoe. One of the worst links was the micro-wave link between Manchester and Kirk O’Shotts. These tests showed the amount of work which would be necessary if a satisfactory colour service using NTSC on 405 lines was to be introduced. At this time there was concern that the UK was still on 405 lines while the continent was on 625 lines. For the next few years I was working both on colour development, optical standards converters and the use of transistors in television equipment. From time to time I, and other engineers, became involved in demonstrations of colour television to various committees and official bodies but there was no pressure for a colour service. Transistors were beginning to be commercially available which could handle the bandwidth necessary for television applications but were unable to handle a NTSC type colour signal. However the reduction in power consumption and heat generated by transistor equipment was so great that work went ahead on the assumption that the problem of handling a colour signal would eventually be solved. The Government’s decision that future services should be on 625 lines and BBC 1 would also eventually go to 625 lines meant that colour would start on 625 lines which required a wider bandwidth and hence produced more difficulties in the design of transistor equipment handling NTSC signals. In the early sixties the French were working on a colour system called the Henri de France system designed to overcome the defects of the NTSC system. The French system became the SECAM system and the French were pushing it to become the European Standard for colour television. The decision that all television services would be on 625 lines and the 405 line service would be closed raised problems in studios as it was impractical to generate programmes on both standards simultaneously. At this time John Bliss’s Recording Section was working on recording and the problem of standards conversion. The latter project had the greater priority and seemed to require better cameras, better display monitors and lenses, but improvements in all these areas only gave marginal improvements. Peter Rainger in that Section suggested a new approach which needed neither displays nor cameras and of course was greeted with scepticism. This process involved cutting the picture up into vertical strips and storing the signal of each strip on every line in an electronic store, such as a capacitor. The stores were then read out at the new scanning rate to produce the signal for the new standard. In this case the 405 line picture was sliced up and stored and read out at 625 lines. Tests proved that this worked for monochrome transfer from 405 to 625 or from 625 to 405 and hopefully would eventually be able to convert colour signals. From 1954 to 1960 Designs Dept was involved in the various tests of a 405 line NTSC colour system and the problems which needed to be overcome if it was not to fail as the initial launch of colour in the USA had done. From 1954 to 1957 Neville Watson, Tom Worswick, myself and other Designs Dept engineers together with Tony Stanley from O.M [Operations and Maintenance]. were involved with colour using NTSC on 405 lines. These transmissions were from Alexandra Palace after shut down at 11pm on Monday, Wednesday, and Friday and at a later date from the newly opened Crystal Palace transmitter. In order to stimulate interest in colour television, Research and Designs supported by O.M, in January 1957 staged a demonstration of 405 line NTSC colour over the Crystal Palace transmitter to members of both Houses of Parliament in the Palace of Westminster. This was followed in August 1958 by doing an O.B. from the Military Tattoo at the White City stadium. In 1961 a week long demonstration of colour television on 405 lines using NTSC was given at the Radio Show at Earls Court. This was repeated in 1962 using a proposed 625 line NTSC system now that a date had been given for the phasing out of the 405 line system. In July 1962 Designs Dept was involved in the test transmission of colour television over the Telstar satellite using equipment modified in the Dept to work on 525 line NTSC. A coder, decoder, colour bar generator, and colour monitors were taken to Goonhilly to be used over the satellite and pictures were exchanged with Andover in Maine. Although the BBC was satisfied with the NTSC system it was felt that if at all possible a common system should be used throughout Europe. Designs Dept then began work with CFT in Paris on their system which began life as the Henri de France system and had by then become the SECAM system. In July 1963 Designs Dept staged a wide ranging demonstration for the E.B.U.to compare the performance of the NTSC and SECAM systems over the television distribution network which was readily accessed from Western House. At this meeting, Dr.Bruch of Telefunken brought PAL equipment, a system they were proposing so that its performance relative to the other systems could be assessed. As a result of these demonstrations it became apparent that three systems needed to be considered. Neville Watson played the leading role in this work particularly stressing the importance of receiver design if colour was not to repeat the American catastrophic start. The receivers needed to be stable, give good colour, and have few controls. Following this E.B.U. demonstration Designs involvement in colour television increased further with participation in tests over the Eurovision network using all three systems. The longest test was between Alexandre Palace and Moscow and a team of Designs engineers went to Moscow for the tests. In 1965 D.E., Sir Francis Maclean, gave the Faraday lecture and Designs Dept played a major role in the staging of the colour displays used for the lecture. The logistics of this event, which was staged in several locations around the U.K., were handled by Geof Larkby. In late 1965 the Post Master General, on advice from the Television Advisory Committee, recommended that a colour television service should be started on 625 lines. Although the B. B.C. favoured the NTSC system it was keen, if at all possible, to have a common system in Europe. This meant that various competing systems appeared and a lot of work was required to assess them. Designs Dept became involved in designing and building coding and decoding equipment so that the various systems could be compared under operational conditions found in a broadcasting system as well as the performance of the home T.V. receivers needed for them. The systems for which Designs built coding and decoding equipment were SECAM 1,11,111,1V, PAL,and NIR. At one time it was nearly a new system every other week. After the extensive tests the PAL system was adopted. Peter Tingey became involved with the receiver manufacturers in assessing the receivers which they proposed to market. If the service was to take off it was imperative that the receivers were reliable, gave colour rendition, and easy to use to avoid repeating the American colour launch experience. The colour service was scheduled to begin on the 1st July 1967 with the televising of Wimbledon. This involved Designs in much work to produce the PAL coding, decoding and distribution equipment to handle the PAL signal. Work was also going on with colour separation overlay and this was reaching the stage where it could be used operationally and equipment was built for use on the weather forecasts. In the early 1960's the work of Designs was dominated by colour but much other work particularly on the automation of transmitters and the design of small transmitters was being carried out in the drive to reduce overall staff costs and improve coverage. As occurred so often there was Government pressure to reduce BBC costs and question the licence fee. This resulted in the BBC being turned over by the management consultants McKinsey. Their brief was to reduce costs and they questioned the need for the BBC to undertake various activities rather than have the work done outside. Designs seemed to be an enigma and they felt it should be either merged with Research Dept or abolished as they believed that the work could and should be done by industry. After several months of deliberation the dept was reprieved but a complex paperwork system was introduced. This required all work to be approved by the appropriate Chief Engineer before work could begin. This resulted in a flood of paperwork and staff to process it. Requests for every piece of work, no matter how small, were made to the Chief Engineers, who soon saw the madness of the proposal. However, a modified system survived which satisfied the management so real work could be done and we got photocopying facilities. While the colour work was in progress the Dept's O.B. team staged a number of O.B.s from unusual locations such as a submarine. This work was done by Geof Larkby and Jimmy Moon. Progress was made on using transistors and early integrated circuits in television equipment. The change from 405 to 625 lines had increased the bandwith required from 3MHz to 5.5MHz which made their use more difficult. The advent of colour, with its high energy at 4.43MHz posed additional problems. However the reduction in power requirements and the lower heat generation made their use essential wherever possible. In 1969 Neville Watson became Chief Engineer Television and Designs went through a period of frequent changes of H.D.D. First there was Dr.Maurice, from Research, then Peter Rainger and then Eric Rout from Research all in a couple of years. While this shuffling was going on at the top Tom Worswick as Head of Transmission Group and myself as Head of Studio Group kept the Dept ticking over. Work was continuing on Ceefax and Designs felt that it should be used to assist those viewers with hearing difficulties as this would also help to establish a good reason at high level to justify the Dept's existence. This work was done in Bill Hawkin's section and he established good working relations with the Television Service resulting in some programmes, such as Blue Peter being subtitled. The challenge lay in how to effectively sub-title live unscripted programmes. The Dept looked at the use of palantype machines as used in the Law Courts as well as devising special keyboards to generate words and phrases specific to a particular programme. A study was made to try and determine how many different words were needed for a satisfactory result and the newspaper publishers were consulted on this. Work was also done in collaboration with Leicester University. As printed circuit layout became more complex and multilayer boards were being used the Dept began to use Computer Aided Design to achieve an optimum layout. In July 1975 I became Head of Equipment Dept a post I held until I returned as H.D.D. in 1980 and Eric Rout became H.E.D. The main area of greatest activity in 1980 was the application of digital techniques to all areas of broadcasting and in particular the work towards a common standard. In the transmission field the automation of high power transmitters at Woofferton, Skelton,and Rampisham occupied much design effort as did the work on the monitoring and control centres for transmitters. The work on these projects helped greatly to justify having the department. Each year the department had a stand at the International Broadcasting Convention and engineers were encouraged to present papers on their work. At these Conventions our equipment was exhibited and firms took out licences to manufacture items of interest to them. In Feb 1985 I retired and handed over to lan Millar. I enjoyed my time in Designs and was pleased to have worked with such dedicated people on the leading technical developments in broadcasting spanning many years. |