BECG The Broadcast Engineering Conservation Group Mon, 10 Feb 2020 09:34:18 +0000 en-GB hourly 1 BECG 32 32 How engineers kept Z Cars on the road Sun, 26 Jan 2020 16:15:55 +0000 Continue reading "How engineers kept Z Cars on the road"

Dan Cranefield writes about the time that MCR23 was pressed into service when the LMCR was damaged.

Ariel article MCR23 conversion.

“The Ariel article took place after the LMCR was involved in an accident (21 Aug 1975) on the way to a Z Cars shoot near Ascot and we had to convert MCR 23 (which, in the article appears to be still a monochrome scanner). I cannot remember what it was like but we installed the two Fernseh KCR 40 cameras and CCUs over one weekend so that it could be used from the Monday while the LMCR was repaired.”

Project Vivat pages moved Sat, 25 Jan 2020 09:55:25 +0000 Continue reading "Project Vivat pages moved"

We have moved the content of the old “” site to the BECG website so it will be kept with all our other projects. The old site will be redirected to this one in due course.

Please see the “Project Vivat” page for the entry point to the pages.

Scale Models Sat, 21 Dec 2019 15:31:46 +0000 We’ve added a new “Scale Models” page which shows off various modelling skills, from commercially available items, via modified items to “scratch built” models.

Privacy policy updated Sat, 07 Dec 2019 11:28:52 +0000 We have added “Koko Analytics” to the website to collect anonymised visitor statistics, this does NOT use Google. Please see the Privacy Policy page for more details.

New articles Wed, 27 Nov 2019 20:31:27 +0000 Continue reading "New articles"

Some new articles have been added recently.

Making Old Television Technology Make Sense by Paul Marshall discusses, how material artefacts can help us understand television’s history more fully.

Dan Cranefield, Senior Engineering Manager, BBC Tel OBs and ex BBC Radio Links has kindly sent us a couple of articles with accompanying photos: The Royal Wedding of July 1986 which discusses the use of the (unfinished) Type 6  Scanner and Radio Links from Outside Broadcasts in the 1960s which shows the time before satellite uplinks came into use.

Radio Links from Outside Broadcasts in the 1960s Wed, 27 Nov 2019 20:19:15 +0000 Continue reading "Radio Links from Outside Broadcasts in the 1960s"

By Dan Cranefield, Senior Engineering Manager, BBC Tel OBs

Dan Cranefield recalls the days before satellite uplinks.

During the 1960s, before the days of satellite uplinks, the vision signal from an OB was carried back to the receiving points, usually transmitter masts, by microwave links, often involving several hops as every link had to be line-of sight, with no obstructions in between. The receiving points in London which had permanent receiving equipment were Swains Lane in Highgate, which had a 90ft-high mast, and Crystal Palace where the equipment was about 300 ft. up. These receivers could be frequency-tuned remotely and the dishes rotated remotely of course.

London Tel OBs’ base at this period was the Palace of Arts, Wembley, and there was a separate Radio Links department. There were three sorts of link in use in the mid 1960s which were a BBC designed UHF, an EMI type where the transmitter or receiver was mounted on the front of the 4ft diameter slotted dish and a TRT type where the equipment was mounted at the rear of a similar diameter solid dish.

If the distance from the OB to the studio was short then BT cables could occasionally be used instead but with equalisers installed at intervals. Sometimes the distance from the OB to the BT exchange involved BT vans every few hundred yards! I have known this to happen but this was a fairly rare occurrence. Some regular venues had permanent cabling to the BT exchange.

Depending on the location of the OB the first transmitter could be mounted on a suitable roof, or on an “Eagle Tower” which was a lorry-mounted extendable mast reaching up to 60 feet. There were also originally two “PTAs” each of which had a Merryweather fire-appliance-type ladder which reached to 100ft but this was limited in capacity and rather wind-dependent. An Eagle Tower had to be rigged while the mast was in the vertical position at 30ft and the PTA was rigged in the lowered position using a ladder. So staff, like me, working on Radio Links, had to be fit and not afraid of climbing vertical ladders or of heights! I don’t ever remember being asked about this. I also had to take a BBC driving test because Land Rovers, often with towed 1-ton generators on the back, were frequently needed at mid-points.

Eagle-Tower Nottingham-Ice-Rink-1961

There usually needed to be a mid point, or sometimes more than one, if distances or land contours demanded it and this would be on high ground and sometimes a water tower was often used, which are always built on high points. At a mid point the roof of the radio link van could be used in exposed places, or an Eagle Tower if trees or buildings were a problem. The longest individual link I remember was Walbury Hill, outside Newbury, to Crystal Palace which was about 50 miles if I recall. At each mid point a receiver converted the signal back to video for monitoring and then converted it to a link on a different frequency for onward transmission. A generator would be needed, towed to site by the radio link van and a spare generator would be needed if there was no mains supply which would be towed to site by a Land Rover. This vehicle became the crew transport in some cases.

Lickey-Hills-1961 Lickey-Hills

To set up each Radio link each crew had an “RT” set on a frequency of 74.7 MHZ for their communication. Each would be given co-ordinates to the previous or next location and the appropriate frequency to use for each link. When ready to set up the transmitting crew would point in the correct compass direction and the receiving crew would pan around until the signal was found and final adjustment would be done at each end until the signal-noise ratio was at its best and within the standards required. All calculations were done using contour maps and calculations by the office staff beforehand and, in the case of a link or series of links from a site not used before, (and there were many!), a test would be carried out well in advance to check that it worked.

© Dan Cranefield 2019

The Royal Wedding of July 1986 Tue, 26 Nov 2019 19:18:39 +0000 Continue reading "The Royal Wedding of July 1986"

By Dan Cranefield, Senior Engineering Manager, BBC Tel OBs

I was the Senior Engineering Manager in charge of all the technical arrangement for the Wedding and in charge of the main site at Westminster Abbey, working to the main Producer, Tim Marshall.

I was the logical choice for this role as I was the technical EM for all programmes at the Abbey at that time. However, all the other remote sites were individually organised by the appropriate site Directors in association with each site’s Engineering Manager. These other sites were Canada Gate, by Buckingham Palace and Admiralty Arch in The Mall, with a few individual cameras fed back to the hub via radio links. The complicated communications required were organised by Mike Jordan of Tel OBs Communications Department.

The “hub” vehicles, comprising scanners, a sound mixing vehicle, videotape vehicles, communications vehicles and generators for vehicles and lighting were parked on temporary portable roadway panels to protect the Abbey’s grassland and parked adjacent to the North Door of the Abbey.

Normally, such an important and complicated programme would make use of, as the main hub, the Central Colour Mobile Control Room (CMCCR), which had facilities for the large number of cameras and remote video and sound circuits needed but this vehicle was unavailable because it was required to be at the Commonwealth Games at the same time. It was decided that the only vehicle which might be able to accommodate such a complex programme as a Royal Wedding was the first of the new Type 6 scanners which was not then even complete, and, I believe, due to go to Wales for its first months of operation.

The advantages of the type 6 scanner over the current type 5 scanners were that the production area was a little wider and the monitor stack could also be extended outwards by about a foot so there would be space available to accommodate an extra row of small monitors in front of the production desk. The Producer needed to be able to see pictures from all the local cameras and all the remote sites individually.

Although the type 6 had no cameras of its own installed, Abbey cameras all being operated from the adjacent type 5 scanner, the vehicle was effectively still being “brought into operation” because the engineers on the “crew” were from the Planning and Installation Department, but with help from our engineers. They all did an excellent job; the arrangement worked very well and the programme ran very smoothly with no major hiccups.

There was a certain amount of controversy, though, beforehand because one of the commentary and camera positions was on the triangular island in front of the Queen Elizabeth Conference Centre on the other side of Broad Sanctuary, the main road via which the royal procession would approach the West Door of the Abbey. Cabling was required to feed this position, so, by negotiation with builders who already had a lot of scaffolding surrounding the Middlesex Guildhall, now the Supreme Court, I requested a scaffold bridge be erected across the road to carry all the necessary cables from the scanner to this site. This did not go down well with the hierarchy nor Buckingham Palace because the royal procession, including the queen, would have to pass under it, a security problem. They were also concerned about the visual impact so it was painted dark green. However, a photo from the high camera position, including my scaffold bridge, was put on the cover of the BBC Transmitting Stations booklet issued the following year, so it obviously was not too intrusive.

Because of this controversy, shortly after the programme I was requested by BBC Events to organise a duct to be installed under the road so that this problem would not occur again. This I duly did and involved a number of site visits and negotiations with Westminster Council, the Gas Board, The Electricity Board, British Telecom and others, all of whom seemed unsure as to exactly where their assets were positioned! I was also informed by LUL that the brick arch over the District Line tracks was only 18 inches below the road surface, so, when the gas board said they had a 3ft diameter gas main going across the road I was a touch sceptical! Whether this duct ever received any use afterwards I do not know.

BBC-Type-6-Scanner BBC-Type-6-Scanner-Engineering BBC-Type-6-Scanner-Production BBC-Vehicles-Outside-The-Abbey-1986

© Dan Cranefield 2019

New additions Sat, 23 Nov 2019 12:29:30 +0000 Two more BBC trucks have been added to the projects page:

Making Old Television Technology Make Sense Sat, 23 Nov 2019 12:16:17 +0000 Continue reading "Making Old Television Technology Make Sense"

A new approach to technological television history and conservation

By Dr Paul Marshall


How does traditional analogue television work? That’s a question beyond the comfort zone of most media historians who may not be familiar with analogue electronics. Even young engineers know little of thermionics, cathode rays and a myriad of other forgotten technologies. This important facet of television’s history is now only recorded by older engineers and by amateur groups who collect these technologies. In this paper, I will show by using examples how material artefacts can help us understand television’s history more fully.

Keywords: broadcasting, engineering, television, conservation, restoration, preservation

How to Cite: Marshall, P., 2019. Making Old Television Technology Make Sense. VIEW Journal of European Television History and Culture, 8(15), pp.32–45. DOI:


Read the article here:

Central News follow-up Wed, 20 Nov 2019 21:59:16 +0000 Continue reading "Central News follow-up"

ITV Central News have posted another video to YouTube, this one is a follow-up item about the event at BCU.

It includes interviews with Chris Perry of Kaleidoscope, Michael Steele and Dr Paul Marshall of BECG.