Portable combined Coin Box and Telephone used in STD areas and can be found with a metal retainer on the right hand side of the case around which the cord is wound.  Regularly found in hospital wards and in BPO rural exchanges (used to check the exchange Coin and Fee equipment) until the introduction of Electronic Exchanges.

Initially supplied with a red handset, cradle, red dial with Chaplets and a red number ring, this coinbox was later fitted with a clear dial and blank number ring.

Introduced circa 1966.

Portable, with a handle that fixes to the rear of the case or bolted to a wheeled trolley.

Mechanism cover lock is the Lock No. 39 and the cash container used a Lock No. 41.

The cash compartment is located at the rear and is a small pull out tray.  The customer would have been given to keys to this lock, to allow them to empty the cash box.  Due to it's small size these coin boxes were always being reported as having coins jammed in them.  The cash box would be full and then the coin chutes would fill up until the coins reached the money slots.

Fitted with either a Bellset No. 47 or a Bellset No. 49.

Descriptive Leaflet DLE531

DLE 531
February 1970

Telephone Apparatus
Portable Pay-on-answer Coin-box

The service offered to your customers can be increased, and new ones possibly obtained, by renting this bright-red portable coin-box and encouraging people to use the telephone.  It can be placed at any convenient point on your premises, where it will soon gain attention.  The facility can also be publicised with attractive notices, provided free of charge.  The customers pay for their own calls as they are made, and the renter profits from a rebate on the call charges.  The coin-box is normally connected by means of a long cord and plug-and-socket arrangement so that it can be moved to the most advantageous position during the day and locked up at night, if required

Both local and long-distance directly-dialled calls can be paid for as they are being made.

The coin-box takes sixpences and shillings, which are collected in a locked cash compartment.  Only the renter has the key.

The arrangement is simple to use, and full instructions are given on the front of the coin-box.  A caller dials first and pays when the call is answered and a pay-tone is heard.  The tone is heard again when the time paid for has been used up.  To prolong the call, more money can be inserted in the coin-box at any time during the call or as soon as pay tone is heard again.

Directly-dialled calls are charged in 6d units.  The time bought for a unit varies with the distance, and extra time is allowed on all calls during the cheap rate periods.  Full details of call charges and the times allowed for different distances are provided in a dialling instructions booklet.

The renter gets a rebate on the call units.  On the telephone account, a charge of only 4d is made for each unit for which 6d was collected by the coin-box.

Trunk calls which cannot be dialled directly are obtained by dialling the operator who will say when and how much money should be put in the coin-box.  For this type of call, time is bought in 3-minute periods and the renter gets the coin-box fee (is a call during the standard rate period and 6d at other times).

Emergency calls to 999 can be made right away, without inserting coins.

Incoming calls are indicated by a bell inside the coin-box.  A bell is also provided near the socket so that calls are not missed if the coin-box is unplugged.


The coin-box is normally provided as a free-standing unit for use on a shelf or counter, but it can be fixed by means of screws in the base to a table or trolley if required.

The handset and its rest are lacquer red, and the body is Post-Office red.  The coin-box is 19.75in high, 8.5in wide, 6.5in deep, and weighs 34 lb.

The cord between coin-box and plug is 25" long; the socket is fitted where convenient to the renter, except that it must be indoors.  When the coin-box is temporarily positioned outside the plug can be passed through a hole to reach the socket.  If the coin-box is in the open, say on a garage forecourt, it should be well protected from the weather.

Additional sockets can be provided by using the equipment in a Plan 4 arrangement.  The coin-box can also be used as the main instrument in the Plan 1A described in DLA 100, although certain limitations are imposed on the extensions.

Wiring a Telephone No. 735 to work on UK Exchange lines

  1. Red wire of new line cord to Terminal B1.

  2. Remove the link between Terminals B10 and B11.

  3. Insert a 3.3K resistor in place of the link on B11 and B12.

  4. Insert a link between B8 and B2.

  5. Blue wire of new line cord to B11.

  6. White wire of new line cord to B2.

  7. Green wire of new line cord should be insulated with tape as it not used.

The above should allow the Coin Box to act like a normal telephone.  You cannot insert money into slots in the same way you would have done in the past, as this Coin Boxes required specialist exchange equipment to operate properly.

Additional pictures




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Last revised: February 11, 2023