Accredited Museum

Please Note: Not all of the objects on this website are on display at the museum.

GAMBRELL BROS EARLY TRANSFORMER, 1930's

Telephone Transformer with Ratio of 5/1 Admiralty Pattern 5869

A0024

INTERNAL WALL TELEPHONE, 1930's

Common intercom used in both houses and offices between the wars (and before), all that was needed was a battery and some wire.

A1227

STERLING PRIMAX INTERNAL TELEPHONE, 1930's

Common internal telephone for homes and offices.
Required only wires, two units and a battery.

A1234

A & B KIOSK BOX BACK BOARD AND TELEPHONE, 1940's

Standard GPO Telephone Kiosk contents with a 200 series Bakelite telephone and 1960's back board.
Notice the area where the Telephone Directories would be housed.
See Item A1147

A0825

A and B COIN PHONE RENTERS UNIT, 1960's

This type of back board and coin box was rented for installation in public houses and hall ways, originally designed by Hall Telephone Accessories Co Ltd around 1930, the design remained the same for over 30 years, only replacing the Tulip Mouthpiece and Butter Stamp Receiver with the Neophone Desk Set 232

A0065

TELEPHONE COVER, 1930's

Used to cover unsightly telephones.

A0045

TELEPHONE COVER, 1930's

Used to cover and hide telephone.

A0952

STERDY APARTMENT TELEPHONE, 1960's

Used for apartment entry system, button is to release door.

A0958

ERICSSON FIELD TELEPHONE, 1920's

Could have been used as a Trench Phone or more likely to be an Engineers Test Set.
Normally with a leather case, but this is missing.

A0026

GPO ENGINEERS TEST SET, 1950's

GPO test set used by engineers to test lines, can be carried over shoulder.

A0027

DICTOGRAPH DICTOMATIC OFFICE SWITCHBOARD, 1950's

The Dictograph Company was formed in 1902 with the first surveillance room bugging device.

A0049

RELIANCE MASTER or EXECUTIVE INTERCOM STATION, 1970's

Office Telephone system with no external line connections.
Transistorised amplifier for microphone in the front for hands free use.
Speaker underneath.
Usually fitted in senior managers and directors offices.

A0048

RELIANCE INTERNAL EXTENSION DESK TELEPHONE, 1960's

Internal telephone system used this phone as a direct method of communication without an exchange.
On the base is marked 15DJITS.

A0025

10 CORE LEAD COVERED TELEPHONE CABLE, 1900's

Telephone cable for underground use, protected by a thick lead sheath.

A0575

STC 1800 41B CABLE, 1930's

Sample of underground telephone cable.
The wires are insulated with paper and the cables were laid in airtight ducts, air was pumped in occasionally to check for leaks, as moisture caused problems with the insulation.

A0568

LEAD BAND TELEPHONE MARKER, 1933

Band marker for ducted cables for identification and destination.

A0580

LEAD SHEATH TELEPHONE MARKER, 1934

Band markers for ducted cables for identification and destination.

A0579

CHROME RING TELEPHONE CABLE, 1930's

Sample of underground telephone cable.
The wires are insulated with paper and the cable were laid in airtight ducts, air was pumped in occasionally to check for leaks, as moisture caused problems with the insulation. the outer covering is Gutta Percha.
This sample is held together by a chrome ring for display purposes.

A0569

NYLON COATED TELEPHONE CABLE, 1960's

Data cable with armour protection, coated in hemp which has been saturated with a mixture for under ground use.
The Transcontinental Cable System or L-carrier system, was developed by AT&T to create a hardened Telecom network using coaxial cable for long distance communications. There were five phases of development of the system, designated by the Bell System as L-1 through L-5. Later versions were hardened against the dangers of the cold war.

The initial systems in the 1930s had 600 voice channels, far more than could be carried by balanced pair carrier systems, and cheaper per channel for high-usage routes. This version was standardized as "L-1" in 1941. Each successive version had at least twice as many channels as the previous version, culminating in the L5 design in the 1970s, which used the then-novel error-control method of feed-forward. AT&T Long Lines built two coast to coast systems of L3 as well as shorter ones connecting major cities, especially the big cities of the eastern United States, as a supplement to the mainstay microwave radio relay systems. Many were later upgraded to L4. L-carrier systems were loaded by multiplexing and super multiplexing Single side-band channels.

A0574

GPO COAXIAL UNDERGROUND CABLE, 1960's

Example of underground coaxial cable on display stand. The inner conductor is air spaced for better performance, air is one of the best insulators. The conductor is held in the centre by nylon discs. For an explanation of coaxial Telephone cables see Item A0574 above.

• Detailed view of the Cable
  

A0063

BT MULTI PAIR PAPER INSULATED TELEPHONE CABLE, 1970's

Telephone cable usually laid in sealed ducts, containing hundreds of wires all identified by a colour code system, the only insulation being paper.
Once installed all joints were made with molten lead wiped with a cloth similar to old lead plumbing, the cable itself had to be kept dry, and the ducts were pumped full of air to check for leaks regularly.

A0577