G.E.C. 1100 Telephone
The G.E.C. 1100 telephone is the ultimate in the design of automatic dial
instruments. In this era of plastics, the fullest possible use has been made of
them. The handcom and case are of Acrilo Butrate Styrene, (A.B.S.) a high impact
thermoplastic, that is colour fast and scratch resistant. Plastic has been used
extensively in the construction of the dial which can be fitted for operation at
either 10 or 18 impulses per second.
The perimeter of the finger plate is "spoked" so that the digits can be more
easily seen without resorting to an external number ring. This reduces the
likelihood of subscribers dialling the wrong numbers. The arrangement and type
of characters can be varied to suit special requirements.
The new single-coil ringer is as sensitive as that used in the "G.E.C. 706"
telephone and is fully interchangeable with it.
All components including the dial, are mounted on the base plate and are easily
accessible, for maintenance by the loosening of two screws on the cradle, which
allows the case to be removed without inverting the telephone.
Like the "G.E.C. 706", the "G.E.C. 1100" telephone has a modern, pleasing
appearance and is comfortable to use. The colour arrangements ensure that there
is a good choice to harmonise with any surroundings. The finger restraining ring
around the dial finger plate both enhances the appearance of the telephone and
ensures that the finger will not slip during dialling.
The handset has been designed to give not only the greatest comfort to the
user, but also maximum efficiency from the transmitter. The shape ensures that
when the receiver is held to the ear in the normal manner, the transmitter is
naturally located in the most effective position. Compared to previous
instruments, the handset is very light in weight and access to the receiver and
transmitter capsules is gained simply by unscrewing the earpiece and mouthpiece.
The transmitter is a new G.P.O. approved design that gives clearer and more
intelligible speech due to lower amplitude distortion and a wider and smoother
frequency response. The new arrangement of carbon granules and electrodes
ensures a more stable performance during the many variations of angle of the
handset in use.
The receiver is of the new rocking armature capsule type and has a very high
electro-acoustic conversion ratio. Acoustic equalisation produces an improved
frequency response and the light-alloy diaphragm increases the ratio of
effective area to effective mass. The magnet is stabilised during manufacture,
so that it has optimum strength.
The whole improvement gained by use of this receiver is not needed on the
receiving side, therefore, a new induction coil has been designed to transfer
some of the improvement to the transmitting side.
In effecting the transfer of gain from receiving to sending side, the highest
practicable degree of sidetone suppression has been maintained. The circuit is
designed to give maximum suppression of sidetone on reactive lines (i.e. cable
pairs), since the vast majority of telephones are connected to their exchange by
The dial used in this telephone is a completely new G.E.C. design, which
uses new materials and a new action, and has the same reliability and
efficiency as its well-known forerunner, the G.E.C. trigger dial. The new dial
can be supplied for operation at 10 or 18 impulses per second; the normal make
to break ratio is 2:1, but on request other ratios can be provided.
A new "spoked" plastic finger plate is fitted which gives a clearer view of the
digits on the number ring without having to use a separate outer number ring.
The dial is lighter in weight than its predecessors.
A light plastic cover can be fitted to the back of the dial to provide
protection of the mechanism against dust. The connexions to the dial are in the
form of a cord included in the cable form for the telephone.
The ringer is also a new design
(shown pictures to the right). It is a single coil type having a d.c.
resistance of 1,400 ohms with an impedance of 17,000 ohms at 1,000 c/s. It
responds to alternating ringing current from hand or automatic ringing machines
and has an optimum response at 25c/s. Coils of higher impedance for multi-party
working can be fitted when required.
The cradle switch has been designed to eliminate any likelihood of sticking
plungers. A new type of springset is fitted which still retains the twin contact
effect, but gives more control over the adjustment and tension of the springs. A
transparent plastic cover is fitted over the springs to prevent dust
accumulating on the contacts.
To avoid excessive volume on short lines caused by the high efficiency of
the "G.E.C. 1100" telephone, a circuit shunt is fitted. This can be easily
disconnected when maximum volume is required. Alternatively, a fully automatic
volume regulator can befitted, or supplied separately, when specially ordered.
The G.E.C. 1100 telephone is designed and fully tested for service in any
climatic condition throughout the world. Special insulation is included, as well
as adequate ventilation and protection against humidity.
The handset is connected to the instrument by a special P.V.C. covered
coiled cord supplied in colour to match the handset. The rosette cord is also
covered in P.V.C.
A Magneto Extension Bell in the G.E.C. Catalogue No. BE1100 or BE1200
series, can be supplied when specified to provide calling signals at a distant
point or to augment calling signals in very noisy surrounds.
The G.E.C. 1100 telephone can be supplied in the following colours:-
Two-Tone Grey and light Ivory.
Other colours can be supplied against request.
All mouldings are in modern plastic materials having high impact strength and a
high degree of colour fastness (thus ensuring good colour matching when
G.E.C. 1100 TELEPHONE, TABLE MODEL - STANDARD - TEL/61K/ATS
G.E.C. 1100 TELEPHONE, TABLE MODEL - TROPICAL - TEL/62K/ATS
Please state on enquiries and orders: Catalogue number, Colour, whether
regulator is required and characters to appear on number ring. (Unless otherwise
specified, number rings are numbered 0,9 .. .. .. .. .. 1 clockwise).
Take from The GEC Catalogue Leaflet STL19A - Click here
Circuit diagram - KS13418
GEC Telephones 1100 and 1200 overview
The GEC Telephone 1100 was an attempt to simplify the
design of the Telephone No. 706, using a single coil ringer mechanism and a 'circuit
shunt' instead of the normal current regulator. By far the most striking change
was the 'spoked' dial, which was said to make the digits more visible without
resorting to a separate number ring. The dial could be supplied to produce either
10 or 18 impulses per second. The blank plate on top of the case was also slotted
to allow for ventilation.
But, the TEL/61K/ATS did not
have a spoked dial and is more or less a GPO Telephone No. 706.
Two-tone grey, black and ivory.
GEC's subsidiary, the Reliance Telephone Company, certainly used them
but not widely. The product appears to have been a failure.
TEL61K & TEL62K
See brochure photograph below.
The Telephone No. 1200 was GEC's own version of the Post
Office Telephone 706, also known as the 'New
Production model showing the typical 700 type layout with the new ringer.
A prototype is shown above.
The capacitors are non-standard, the switch hook contact set is located between the upstands
and there is no regulator.