Pye Unicam Story

 The Pye Scientific Instrument Centre in York Street, Cambridge

Early Days of the Company

 The first Pye  Company  was  founded  by  William  George  Pye  in  1896  making  scientific  instruments  for  schools  and  universities.

 Sidney William John Stubbens (a foreman at  the Cambridge  Instrument Company)  formed  Unicam Instruments  Ltd  at  Arbury  Road,  Cambridge  in 1934  specialising  in  spectroscopic  and optical  instruments.

Pye Unicam had the distinction of having a direct link with the original WG Pye company and also the original Unicam Instruments company. 

  The two companies designed and manufactured many types of scientific instruments including the famous Scalamp and Interval Timer.


WG Pye & Co Ltd

Unicam Instruments Ltd

WG Pye  & Co Ltd

On CO Stanley taking over the Pye radio business in 1928 and forming Pye Radio Ltd, WG Pye and his son Harold moved the now separate instrument company to premises at 80 Newmarket Road – just the other side of what today is Elizabeth Bridge. 

Here WG Pye & Company Ltd prospered, mainly led by Harold, until in 1946 Pye re-acquired the company back into the Pye Group. This building continued to be used for many years by what became Pye Unicam, and between 1960 and 1967 by Pye Engineering Services. The building was finally vacated in the late 1970s and no longer exists.

Harold Pye and WG Pye Logo

Main Door, 80 Newmarket Road in 1960 with staff

Back Row – John Coupe, John Mabbut, Jimmy Higgins, Eddie Lorimer, Brian Waller

Front Row – Barry Brown, Mick Brown, Colin Place

Unicam Instruments Ltd

The other acquisition that Pye made in the field of analytical instruments was the Unicam Instrument Company in 1947. Both WG Pye and Unicam were instrument makers, but with different products – and cultures.

The Unicam Instrument Company, originally formed in 1934 by the three Stubbens brothers, was set up in premises off Arbury Road in Cambridge. One of the brothers, Sidney William John Stubbens, a foreman at the Cambridge Instrument Company, completed a planning application to construct the original company building in November 1935. The site, opposite the junction of Leys and Arbury Roads, was proposed to house a 60 feet by 40 feet building for the new company.

By May 1940 a further building to house Drawing, Purchasing and Administration Offices and a staff Canteen was proposed. This would be built along the entrance road to the original building. This block was 100 feet long but only 16 feet wide due to the constriction of the entrance road.

Due to the pressing requirement for wartime supplies of optical equipment, a further significant expansion of premises was drawn up and planning permission requested in November 1942. This consisted of an extension to the rear of the original factory block and was of an almost similar size. In addition underground bomb and gas shelters were also planned. This new extension was for optical glassworks, canteen and a transformer block with a floor area of 8,500 square feet.

The provision of shelters was understandable since the site was the subject of repeated German bombing raids in August of 1942, presumably as a result of Unicam’s work on war supplies.

In 1947 Pye Ltd acquired the Unicam Instrument Company along with WG Pye Ltd the previous year. By July 1954 Mr SWJ Stubbens applied for permission to erect a new building of 8,000 square feet to the east of the original and above the underground air raid shelters. This would be used to provide further space for the assembly of scientific instrumentation, in particular infra-red spectrometers.

The front of the new, narrow Administration Block as seen from Arbury Road.

The Administration Block following the Pye acquisition

John Stubbens

Unicam Instruments Ltd Logo

By 1962 Unicam had largely vacated the site and moved into the newly developed facility in York Street along with WG Pye Ltd. The former company at the north end of the new site and the latter company at the southern end of the site. By this time the assembly of Outside Broadcast Vans had been removed from part of this site.

Pye Apprentice Training Centre in the 1960s

However the Arbury Road facility remained in the ownership of Pye Ltd and subsequently became the Pye Ltd Apprentice School and a repair workshop for rental TVs when Pye went into the rental business. The facility eventually became the Pye Telecom Technical Training Centre and also their Service Centre. This continued as such into the 1980s. Finally in 1986 67 flats were built on the cleared site which now make up the Havenfield retirement housing. 

Some pages from the WG Pye Company catalogue of products for sale can be viewed in the document here.

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WGP Catalogue J.pdf
WGP Stopclock.pdf

The brochure for one of WG Pye's most iconic products - the laboratory stop clock

North Gate of the Pye York Street site

Here we see a Pye TVT Outside Broadcast vehicle leaving the nearby York Street, Cambridge site by the North Gate. 

In the background are the original buildings of what, after development in 1962, would become the Pye Scientific Instrument Centre and subsequently Pye Unicam (see below). However, at this time it was used for OB vehicle assembly.

In the aerial site photograph below, this older part of the factory is clearly visible as the darker areas, nearer the camera.

The Times - April 13 1962

Pye Ltd re-acquired the W.G. Pye business in 1946 and shortly afterwards in 1947 also purchased the Unicam Instruments company.

Now as part of Pye Ltd, the two companies moved into a newly built facility - the Pye Scientific Instrument Centre in York Street, Cambridge during 1962 .

However for the next six years the two companies operated quite separately.

Finally, in 1968, the two companies at York Street merged to form Pye Unicam Ltd.


Focussed on the design and manufacture of spectroscopic and chromatographic instruments, their aim was to help solve a host of problems requiring analysis of materials.

Pye Unicam Ltd, York Street site.

Company Open Day - 21st September 1985 

(showing factory layout at that time)

Commemorative Items and Celebrations

Often commemorative gifts were manufactured by the company's model shop.

Here is an example - a small model of the SP500 spectrophotometer converted with a built-in alarm clock.

This was presented to Dick Fearn on his retirement with the inscription reading

From the Directors of Pye Unicam

to Dick Fearn in recognition

of 37 years of loyal service.

And here's Norman Hobbs with the new automatic zinc plating machine that he persuaded the company required! Norman was responsible for the plating, painting and fettling shops.

His retirement presentation piece was an Atomic Absorption Graphite Furnace Head, suitably mounted and inscribed. This celebrated his time with the company from 1964 to 1991.

EV Root Retirement Gift – Model Travelling Microscope

EV (Ernie) Root joined WG Pye & Co aged 14 as an apprentice in 1911. He helped build Pye’s first radio in 1922 and became Chief Development Engineer of Pye Radio Ltd.

Root returned to WG Pye in 1939. Appointed Managing Director when it re-joined Pye Ltd in 1946, he updated the product range including the Scalamp galvanometer, introduced pioneering scientific instruments and successfully led the company until his retirement in 1965.

Ernie Root returned to visit Pye Unicam in 1972, where apprentices presented him with a scale model of a travelling microscope to mark his 54 years, service with the company. 

The three apprentices (l to r) are Peter Wilding (19), Paul Andrews (19) and Michael Firmin (18). The Pye Unicam MD of the time, Dr Peter Starke, can be seen in the background.

On the 3rd June 2023 the scale model was presented to the Pye Collection at the Cambridge Museum of Technology by his granddaughter, Pat Mansfield and grandson Richard Hopkins. Receiving the model from Richard and Pat are Mike Kemp, David Featherby, Mike Wassall and Roger Crabtree.

In addition Long Service Award Dinners and official company gifts were presented.

Two photographs taken at the 1973 Awards Dinner.

The photographs kindly supplied by Dawn Mabbutt who married the late John Mabbutt in 1982

Future Direction

The York Street site thrived, concentrating on Chromatography and Spectrophotometry.

Acquired by Philips in 1967, and at its peak employing 1500 people, it was the UK’s largest manufacturer of analytical equipment.

During 1991 it was divested to ATI (Analytical Technologies Inc) and subsequently in 1995 to the Thermo Electron Corporation, both of the USA.

In 2009 the company collected its third Queen’s Award, this time for Innovation.

Five years later the final factory site in Cambridge closed and the business transferred to Germany and China.

A Personal Account of Pye Unicam's History - By Stan Harrison & David Jamson

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