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Document Repository - Documents from other sources

Technical Manuals

Note that handbooks for telephones and equipment can now be found on the Handbooks and User Guides Page.

2000 and 4000 type selectors - Training Engineering training publication from Telecom Australia for the 2000-type and GEC SE 50 (4000-type in the UK). [1.3 MB]
4000 type selector (SE 50) Article from the Telecommunications Journal of Australia about the development of GEC's SE 50 selector, named '4000-type' by the British Post OFfice. [3.5 MB]
Atkinson on PMBXs Chapter XI from Telephony by J. Atkinson on Private Manual Branch Exchanges. Covers small cordless, larger cord boards, and house exchange system. [2 MB]
Bridgnorth Automatic Scheme 1938 A curiosity sent by Andrew Emmerson from a 1938 GPO document. It shows a map of the exchanges in the Bridgnorth area and their interconnections and proposed conversion to automatic working (191 kB)
Cable Information A compendium of information about cables from 'The Handbook for Telephone Manager and Engineers' published in 1946 by Automatic Electric Company in Chicago. Rather US-centric but with some British & Metric standards. Courtesy of John Mulrane [490 kB]
Cable Simulator A friend built this along time ago to simulate PO cable types to assist with testing equipment. Component values and photos to show construction. [374 kB]
Circuit Symbols Description of scalable images of electromechanical circuit symbols in Windows Metafile format. Download the Zip file (141kB)
Code Card Project Started by Simon Chappell of the Telecomms Heritage Group, this document is a compilation of customer dialling instructions. It contains local dialling codes with a wide geographic coverage. The dates range from the 1950s to the 1980s when local codes were replaced by full national number dialling. Many people have contributed copies of code cards (usually held in a drawer in the telephone base), dialling code booklets and directory pages. Further contributions are welcome. [1.2 MB]
Dictograph Flyer
Dictograph Explanatory diagram
Dictograph Users Handbook
Dictograph circuit for system with one master

Dictograph office telephone systems: a promotional flyer and explanatory circuit diagram, both circa 1936, user's handbook (digital recreation), possibly 1950s, and a circuit for one master station and two subs, dated 1953, converted from a blueprint. Courtesy of my correspondent in Australia. [ 239kB, 512kB & 102kB ]
Electronic Exchange Systems Part 1
Electronic Exchange Systems Part 2
A Century for TXE4
Two articles from The IEE Proceedings by Tommy Flowers, famous for his work at Bletchley on the Colossus computer but by 1971 working at STC on electronic exchanges. The structure and low-level control of the TXE are described in Part 1: Part 2 looks at the registers, common control and the system as a whole. [1.4 MB & 1.3 MB]
An article from the IEE magazine Electronics & Power from 1980 celebrating the 100th installation of a TXE4 exchange from STC with a description of the operation. [814 kB]
Evolution of Edinburgh director system
Deduced from various directory pages by the late Brian Clancy. It follows the progression of the numbering scheme from 1945 with a 5-digit non-director system using Siemens 16 switches through to 1965 with an almost completely automatic 7-digit director system using standard Post Office Strowger switching. 82 kB
French PTT S63 Telephone

Courtesy of John Mulrane a redrawn version of the internal paster label with English captions. [12 kB]
GEC Telecommunications, August 1956 Contents & photographs
GEC: New High Performance from Subscribers' Telephones

Courtesy of Andrew in Australia, the conte nts page of the GEC house mag from 1956 & colour photo of the 1000 range [73 kB]
Followed by the first of two articles describing the design behind the new 1000 range of telephones. [1.6 MB]
GEC 1000 Telephone

The second of two articles describing this new introduction to their range of telephones, the 1000 model. [128 kB]
German Heat Coil & Fuse Ratings

A handy guide to German heat coil and fuse ratings along with the colour code prepared by John Mulrane [107 kB]
GPO Tower
An article about the Post Office Tower's design and construction from the Architects' Journal for June 1966 14pp 4.54MB
GPT Glowphone

A photolumincescent version of the IXT (Statesman) offered by GEC Plessey Telecomms. Promoted as a safety feature since it was easily located in the dark. [855 kB]
Keyphone 91 Leaflet from GEC in 1979 describing the Keyphone 91, a push-button telephone with multi-frequency signalling based on the case of a Telephone No 746. [597 kB]
Krone LSA-Plus Catalogue Krone catalogue of insulation displacement connection products, terminals strips, connection boxes, racks, modular jacks etc. [11 MB]
KTAS DA30 Telephone Danish telephone diagram for the Kjøbenhavns Telefon Aktieselskab (Copenhagen Telephone Company) Model DA 30. Courtesy of Søren Black-Petersen [179 kB]
Line Insulators since 1912 Line Insulators used by the British Post Office since 1912. A booklet produced by the late P.J.Povey, who, at the time, was curator of the Telecommunications Museum in Taunton. Each known type is decribed in details followed by sketches of each type. Courtesy of Andy Grant. 867 kB
Loading of Telephone Cables A 1974 guide from STC on the principles of cable loading and selection of suitable coils. 292 kB
Local Lines, Past, Present & Future IPOEE Paper from 1965. Describes the method of pair provision in the local network. Discusses projected growth for the next 20 years, the new design of flexibility cabinet and line concentrators. 1.77 MB
1. London All-Figure Exchanges
2. London Director Codes - Transfer to All-Figure Numbers
3. London Local Codes - Dialling to adjacent call area
1. Small reminder card published circa 1966. Lists each all-figure code with its geographic location. Courtesy of Jim Reynolds [194 kB]
2. A table of the conversion in the 1960s from the old LETter codes to the all-figure numbers is followed by some explanations of the reasons for AFNs and the complicated process involved. This is an article I prepared with help from Paul Ebling, Andrew Emmerson and Neil Johanesson. 88 kB
3. A list of the dialling codes to places outside the London Director Area within the local call zone, showing progression from 3 to 6 digit numbers. 23 kB
Miniature Automatic Telephone Exhange Article published in Wireless World magazine inFeb 1972, 'Constructing a telephone system for private use'. Some annotations by John Goldfinch. 253 kB
Miniature Relays - GEC Types
Miniature Relays - ITT Types 24/25/26
GEC Miniature Relays catalogue leaflet MRLIB, undated. Sealed and unsealed types in normal and heavy duty ratings. 1.23 MB
ITT Relays Type 24/25/26 Catalogue. These are the familiar Post Office Type 23 relays and it contains a list of the coil and contact details for Types 23/1 to 23/20 and the gold contact types 32. Courtesy of Dick Landau 1 MB
National Telephone Co Telephone No 13 Wiring diagram of the National Telephone Company's Telephone No 13, which later became BPO Telephone No 88. Courtesy of John Mulrane 37 kB
Northern Eletric Telephone Model N1317 Diagram N1317 found in the collection of the late John Goldfinch. It refers to the Northern Electric version of the Western Electric wall telephone Type 1317. NE made the same set as WECo with some additional versions supporting long lines and various party line options. Later models added support for simplex dialling. Includes a page from NE catalogue 1914 showing the N1317 type phone. Also see This Page from Bob's Old Phones 235 kB
OFTEL Guides
1. Telecomms Wiring in business & homes
2. The Wiring Code Part 1
3. The Wiring Code Part 2
4. The Wiring Code Part 3
5. Guide to Data Communications
Published by the Office of Telecommunications after liberalisation of the market to explain the new rules
1. Telecommunications Wiring in Busines Premises and Homes, OFTEL 4 1.1 MB
2. The Wiring Code Part 1: Domestic and other simple installations, OFTEL 5 1.1 MB
3. The Wiring Code Part 2: Business and other complex installations, OFTEL 19 2.4 MB
4. The Wiring COde Part 3: Shared Cabling, OFTEL 21 3.0 MB
5. A Basic Guide to Data Communications, OFTEL 15 1.1 MB
Pasters & Labels A collection of telephone pasters - the labels with a circuit diagram stuck inside the case of telephone. Acquired from various sources. 1.3 MB
Plantronics Guide to headsets
This Guide To Telephone Headsets is designed to introduce you to the technology, explain the rationale behind headset operation. 52 pp 1.6 MB
Plessey 5005 Crossbar System Technical description of Plessey's 5005 Crossbar system. 91 pages with coloured diagrams. 6.8 MB
Plessey Catalogue A catalogue of telecomms products from Plessey from the early 1970s. Contains the brochures for various PAX, PABX, PMBX, telephones and secretarial sets. Courtesy of Ian Ross. 132 pages. 18.5 MB
Plessey Pentex Exchange A special issue of the Plessey Bulletin about the first field trial in public service of the Pentex small electronic exchange. Pentex used reed relays in a crosspoint matrix switch. 36 pages 5.4 MB
Plessey Telephone Secretarial Sets
Plessey Etelphone N1905
Plessey Etelphone N1906
Etelphone Pasters
Etelphone brochure
Secretarial Set Mk VI Data sheet
Secretarial Set Mk VI Brochure
Plessey Telephone Secretarial Sets
Plessey Etelphone N1905 Manual. Equivalent to a Planphone, but all contained in a 706 body. 735 KB
Plessey Etelphone N1906 Manual. Similar to the above. 821 KB.
The paster labels from several different models of secretarial set. 897 kB
Plessey Etelephone systems brochure 219 kB
Secretarial Set Mk VI - similar to the Etelphone systems. Data sheet 307 kB
.... and sales brochure 239 kB
Above three thanks to Andrew Tebbutt
Pneumatic Protection of Telephone Cable Networks An article about pressurisation of cables, probably produced by Drallim Ltd, with some of my photographs added. 67kB
Post Office Electrical Engineers' Journal
Full collection - see Journals page
A new CB microtelephone (Tele 162)
A new switching and transmission plan
Evolution of the inland telecomms network
Index for 1936 to 1946
Index for 1976-77
Portable generating set for manhole lighting
PO Standard Motor Uniselector
Principles of Anti-sidetone Circuits
Telephone Transmission VI
The new 700-type telephone (Tele 700)
The new combined microtelephone (Tele 332)
The Rocking armature Receiver (Receiver 4T)
Institute of Post Office Electrical Engineers Journal, usually abbreviated to POEEJ. The publication where the British Post Office described its network, equipment and practices. The indices are Searchable PDFs, courtesy of Paul Ebling and Jack Ryan. Others from Bill Sayer, John Goldfinch.
A new CB microtelephone. From 1929. Describes the development and characteristics of Telephone No 162 which was introduced in 1929. 1.5 MB
A new switching and transmission plan for the inland trunk network From 1960. Outlines the changes in the network to introduce Transit Switching Centres. 419 kB
Evolution of the inland telecommunications network From the 75th anniversary edition in 1981. How the network has grown from the 1950s through trunk mechanisation and STD to transit and international. Also non-voice from Telex to Datel data networks. 744 kB
Index to Volumes 29 to 38 from 1936/7 to 1945/6. 101 kB
Index to Volume 69 from April 1976 to Jan 1977. 726 kB
Portable Generating Set for manhole lighting From 1952. A suitable replacement for the old acetylene lamps then in use.751 kB
PO Standard Motor Uniseletor From 1953. Operation and construction of the motor uniselector that was widely used in the trunk switching network.1.0 MB
Principles of anti-sidetone circuits From 1956. The theory of sidetone suppression in telephone instrument with reference to the 300 series.361 kB
Telephone Transmission VI. Article from July 1935 setting out the Post Office transmission budget for the telephone network and showing how the network was divided into Groups and Zones for transmission planning. 286 kB
The new 700-type telephone. From 1956. The development of the 700-type telephone which became the basis for the Tele No 706 and the later 746. (OCR version) 665 kB
The new combined microtelephone and bell set. From 1938. Describing the genesis of the Telephone No 332. 451 kB
The Rocking armature receiver. From 1956. The design principles and performance of the Receiver Inset No 4T as used in the 700 series of telephones. 608 kB
Poste téléphonique à transistors expérimental An article from French telecomms journal 'Commutation et électronique' from 1969, describing an experimental telephone using transistors both for amplification and as the hybrid. In French. Courtesy of Andrew Marland 796 kB
Post Office Charge Groups A map of the UK mainland showing the telephone groups on which charging was based. Created by staff on British Railways for their own reference purposes. See also the STD Equivalents List below.
Relay Automatic Exchange - PAX
RAT PAX Technical Description
The Relay Automatic Telephone Company was formed in 1915. It's exchanges used no selectors, only relays. Several private automatic exchanges (PAXs) were installed in the UK. This is the diagram T3413 for one such "Type 10" installation with its Technical Description. Scanned courtesy of Mike Tyrrell [101 kB & 700 kB]
Siemens 100 years of telecommunications
A concise history of Telecommunications at the Beeston site, from 1901 to the Present Day. Covers the period encompassing National Telephones Co, L.M. Ericsson, ETL, Plessey, GPT, Siemens. 20pp, 3.5 MB
Siemens Report W923, Motor Uniselector Courtesy of John Mulrane. This is a detailed description of the construction and operation of the motorised uniselector as used widely in the PO trunk switching network. Excellent photographs. Dated 1934.646kB
STD Equivalents List A list of the Post Office Subscriber Trunk Dialling codes showing the way the routing in the trunk switching network worked. See also the Charge Group map above. Updated May 2014 71 kB
STD Numerical List A numerical list of STD codes based on the Haddenham & Long Crendon dialling instruction book from 1984. This was a crucial period where most of the UK was diallable and before exchange names fell out of use. 220 kB
STD Code Map A map that an unknown person originally produced in AutoCad (originally dated 25-Apr-1991 12:16). The STD Codes on the Map are correct for the era May 1990 to April 1995. It's 893 x 1490 mm so may need to be printed in parts. Courtesy of Mike Ginger. Compare with the later official National Numbering Groups Map (2000)in the PO Documents section. 187 kB
Strowger Selector Operation Description

Thanks to Wim der Kinderen a presentation giving a very clear set of explanatory diagrams on the operation of a various types of Strowger selector during call set up. 45pp [1.2 MB]
Subscribers' Extension Plans A booklet prepared by the late Thomas Rhoden with descriptions and sketches of the various plan workings used by the Post Office. It also includes the N-diagram numbers for each. Updated to include Plans 108 & 108a 823 kB
Subscribers' Group Service Developed in the 1930s, the Subscribers' Group Service was essentially a rural satellite exchange. It allowed up to eight subscribers to be connected back to a parent exchange by just two pairs. The object was to provide cheaper telephone service to subscribers who make only a few calls. This article appeared in Telephony by Herbert & Procter, Pitman, 1938. 82 kB
Telephones: Their construction and fitting A practical treatise on the fitting up and maintenance of telephones and their auxiliary apparatus. The first two chapters on Receivers and Transmitters of a text book by F.C. Allsop published by E. & F.N. Spon, London 1895. Courtesy of John Goldfinch. 2.7 MB
The Telegraph Pole An IPOEE paper from 1933 by W.H. Brent. A comprehensice survey of the subject, from the choice of tree, through the preservation process to the life expectancy of poles. 4.8 MB
The Mitel Story
A lavishly illustrated history of the company issued in 1998 to celebrate its 25th anniversary. 56pp 8.8 MB
TIM 2000
TIM 2015
TIM 2000: A digital recreation of the good old-fashioned Post Office Speaking Clock with the voice of Pat Simmonds.
TIM 2015: The concept revisited with more options for synchronisation, and a choice of voices - even your own. [both in HTML]
Towards a digital communications future Article from BT in-house Electrotechnology magazine on BT's plan in 1986 for future digital network for both voice and data. 213 kB
Uniselector BPO Type 2 Adjustment Instructions ATE (Automatic Telepone and Electric) instruction " Adjustments for Uniselector - single magnet, (BPO) Type No 2. Courtesy of John Hein 1.2MB kB
Western Eletric Vacuum Tubes for use with Amateur Radio Catalogue from 1933 of valves made by the WeCo. Normally only available to the trade, they were made available to amateurs as a 'concession'. Looking at the prices at the end it wasn't much of a concession. Thanks to Steve Cichorsky for posting this on Greenkeys mailing list. 2.1 MB
What is IP?
IP Technical Overview 1. A guide from Cable & Wireless to the technologies and standards underlying the delivery of IP services and applications.
The Yuasa little red book of batteries Guide from the Yuasa battery company to the characteristics of lead-acid batteries. Typical applications, choice of battery, charging, care and maintenance, safety and disposal/ re-cycling. 632 kB
Repository Index