Now you can have a small internal telephone system for less outlay than any other private automatic installation.
The PAX61 has all the simplified wiring advantages of an automatic exchange system, and benefits further from the compact design of its automatic switchboard. Up to 10 lines can be incorporated in this economical network, and there is the added facility (by the use of slightly heavier cabling) of being able to have some of the extensions located as far as six miles (9.65 km.) away.

Elegant telephones
Ordinary dial instruments are used for the installation, and elegant Centenary Neophones or the latest British Post Office design can be supplied. If you reach the stage of expansion where a larger exchange becomes necessary, the telephones and wiring do not become expendable; they form the basis of your larger network.

Uses mains power
Designed around the outstanding AEI Miniature Uniselector, the PAX 61 automatic switchboard plugs into any A.C. mains supply. The system operates on 50 volts D.C. and the board contains its own A.C. mains unit to convert and rectify to the supply required.

The whole compact switchboard measures only 10.5 in. by 10.5 in. by 6 in. (26.67 cm. by 26.67 cm. by 15.24 cm.) and weighs just 16.5 lb. (7.48 kg.).

How it works
By dialling a single digit (0 to 9), a caller can ring any other number in the system. For as long as the caller wishes, the intermittent ringing common to all private automatic telephones will continue until the call is answered or the caller replaces his handset. Dialling tone is provided.

Executive priority
Interruption facilities for executives from selected phones can be provided; a simple button is all you see added to the telephone, since only one extra wire is run into the instrument concerned. When this is used while a line is already being called, the ringing caused by the first (non-priority) caller is automatically stopped.

Hundred per-cent privacy
Since only one talking circuit is provided when a connection is made, all conversations are strictly private between the two people involved. This complete secrecy applies to all extensions.

It is more economical and less troublesome to have your PAX61 installation on rental. Charges are low and all maintenance is absolutely free. Alternatively, direct sale can be arranged, with a maintenance contract drawn up to suit your requirements. (Please note that in some overseas areas, only direct sale can be considered.)

Extensions far and wide
The automatic switchboard of the PAX61 simplifies the normal wiring runs of a system by allowing ordinary telephone cable to be used-only one pair of wires to each instrument. In addition, it permits extensions to be located as far as six miles away, merely by use of heavier gauge wire.
Up to 3 miles, 23 s.w.g. (0.023 in. dia.)
Up to 6 miles, 20 s.w.g. (0.031 in. dia.)

(For the technically-minded, loop resistance without telephones is 400 ohms.)

and if your business expands
The PAX61 allows you in the first place to benefit by the simplicity and inexpensiveness of an installation specifically designed for up to 10 lines. Yet all the telephones, all the wiring, is retained when you feel big enough to warrant more lines and facilities.

Taken from Sales Brochure PD6/30

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Last revised: October 13, 2012