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Directorate of Telecommunications
EQUIPMENT; Speed Traps
By: Steven R Cole
Introduction
This part of the library contains a collection of scanned photographs related to speed traps, or speed enforcement in today’s jargon.
Marconi Peta Meter
Developed in the early 1960’s, this is thought to be the first road speed meter used by the Police Forces and maintained by the Directorate.
MultaNova Speed Camera
The first ten images were part of a collection retrieved from Weyhill sometime prior to its closure. They were mainly taken on the A303 at Picket Twenty near Andover and show the equipment in use at the time, and where applicable, the captured images with recorded speed and twenty-four hour time superimposed. It is thought that this was a project being run by Hampshire Police, with support from Weyhill Maintenance Unit.
Comments from Alan Copperwaite (6/12/05 & 12/1/06)
“The speed trap equipment was called MultaNova, a Swiss device with a built-in 35mm camera. I have some further pictures taken in 1968 when we originally tested it on the Watford Bypass. I still have the original 35mm negative roll but had the pictures digitised as the film was getting old. The MultaNova was a bit ahead of its time with its capability, but the supporting tripod had a tendency to collapse in use and it ate 2x 12v lorry batteries, they lasted about 45 minutes if you were lucky!
The other two things I recall was that when we were testing the unit, it had a flash included for night use. This can be seen adjacent to the camera on the middle slimmer unit in the pictures. We decided to test this aspect for completeness just as a Hertfordshire traffic police car went past. The officers of course stopped and wanted to know all about us and the equipment but they were less than impressed by the flash because in their view it 'would seriously distract the motorist from concentrating on his driving'. Obviously times and views have now changed. In the pictures the police have actually mounted the small remote unit above the radar but this was intended to be inside the car or even further down the road with the officers stopping the vehicles.
When I was setting up the MultaNova equipment in the CCE lab, I was a little concerned about health hazard from the microwave unit as there was no particular indication as to the power radiated from the system. I mentioned this to my management (Norman Butler and Ray Stoodley), who mentioned it to whoever was responsible for safety. The safety officer then came and put a low plastic yellow guard across the door of the laboratory, and walked away leaving me to stew in my microwaves inside. So much for Health and Safety at that time! Shortly afterwards I went to take over the UHF lab.”
Comments from Alan Copperwaite (12/1/06)
“Indeed this was the first portable speedmeter to be used in the UK. The early versions of these meters could only read up to about 80mph and had to be modified to read over 100mph. This was obviously known by many speeders, particularly bikers, as they could not be prosecuted if they went over 80mph and their speed could not be read.
In about 1969-70 Marconi developed a modification to the PETA meter to allow it to read up to and above 100mph and as a HO representative I went to Marconi at Chelmsford (Great Baddow) to see the mod and a new meter dial to be fitted. The people at Marconi for some reason, seemed to want to check that we, the Home Office, could satisfactorily implement the modification. So accordingly I was led to a workshop/lab where I was asked to carry out the work. I think if I had been a bit older and more sure of myself I would have told them that it was not my role to prove my competence to them! However what mainly surprised me was how poor the accommodation was for the technicians working in the Marconi workshops. They were in very old-fashioned warehouses with high ceilings, battered wooden benches, miserable lighting slightly assisted by high windows and soldering equipment we would have probably thrown away in Harrow. It was difficult to see how the technicians could achieve high quality work under those conditions and I began to realise how well we were equipped in CCE. Despite the facilities I completed the modification, apparently to Marconi's satisfaction and the change was successively put into place throughout the HO units. It was a revealing insight into the working environment at Marconi at that time.”
Comments from Mike Brain
A programme of modification to all PETA meters in use by the Police Forces was carried out by Weyhill MU during the early-mid 1970’s to permit speeds of up to 100mph to be registered. The credit for much of the PETA Meta work done at Weyhill goes to Norman Tuffin.
I was given the opportunity to test out the first batch of meters to ensure they accurately recorded these high speeds by driving a Police Triumph 2.5pi car on Thruxton Race Circuit and placing the meters at the fastest point on the track!
Comments and 1965 Photo from Mike Rignall (15/2/15)
In far off days I was very conversant with this equipment when at Marconi at Gt.Baddow I designed all of the electronics. The prototype was being tested by myself and Morrison Sellar (also still with us) beside the West Hanningfield reservoir near Baddow, It was the final check before a demo to Cambridge Constabulary in the afternoon. We carefully packed up the equipment into the back of the Hillman van and drove off. There was a slight bump. Morrison and myself looked aghast, we realised we had not picked up the meter, which was now damaged.
As two young engineers at the start of a (hopefully) great career ahead, we had the task of going back to the labs and telling Mervyn Morgan, our chief, of the disaster. However to cut a long story short, the case was quickly reshaped by the metalworkers, the Ernest Turner meter was quickly re-sprung and I repaired the cracked tracks on the PCB.
The demo took place and the tale of the ruggedness of modern transistorised equipment made a fine talking point. It was interesting that great play was made of the all transistor component, in fact there were two valves, the X band klystron and a 12AX7, the latter was used as a high impedance store for the voltage developed from the F to V converter. Alas, CMOS op amps were decades away. I often think how kind nature was to make the Doppler frequencies involved were at the rate of 30 Hz/ m.p.h, with OC70's with an fb of not very many KHz it was a good job that it was not Q band, since Q band and 100 m/p/h would have related to nearly 10 KHz and if I remember correctly the pulse converters in the F to V section were getting quite tricky.
I just glanced at my router, 2.5GHz comms for peanuts and a processor with about 60 million active devices. Things have come a long way in 60 years.
Having graduated, the aforementioned Mervyn Morgan said, "Mike, I think transistors are going to make an impact, I am sending you back to Borough Polytechnic". He was not far from the mark !
I had quite an interesting trip back through time having looked at the PETA images. It was quite an experience designing the electronics, since as a junior engineer I was really on my own as all of the senior engineers could design anything with valves, but these odd things with 3 leads and a low input resistance were rather alien to them. It is still fascinating to look at the advances in electronics, since I graduated with a good knowledge of valve technology (which I never used) in 1956 and to now look at modern digital technology, which at that time was unimaginable.
Imagine an Intel "processor room" with 60 million 12AX7 s. I still recall the first computer at Baddow, 6 mathematicians to program it and 2 full time engineers to keep it running. I later learned that it had the power of a Commodore 64 (remember them?). Thank goodness for integrated circuits and Bill Gates.
Related Comments from Marconi Radar History can be seen here.
Acknowledgements:
1. Alan Copperwaite for the descriptive text used in this article. It provides a fascinating insight to aspects of work carried out by Alan during his time with
the Directorate in respect of these equipments.
2. Mike Brain and Mike Rignall for their inputs.
3. John Leary, Peta Meter photos
4. MultaNova photos came from Weyhill MU
5. Marconi Radar History link from Jan Kozminski.
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