Radio System Controllers and Control Panels 1947 - 1997
Note: The chronological order is approximate and the research on-going
This was the first generation of operator control units and control panels designed to support the original Pye fixed stations types PTC104, PTC104A, PTC105, PTC105A, PTC106 and PTC106A.
Starting with the launch of the Pye Radio-telephone system concept in 1947, two types of operator control arrangements were made available. Extension control where the fixed station transmitter/receiver and the operator control unit were located within 200 feet of one another, and remote control where the fixed station was located a considerable distance away from the control operator, and Post Office telephone lines were used to interconnect the two sites.
Both types of controller were small desk-top units constructed in veneered wood cabinets, containing a loudspeaker, volume control and transmit/receive switch. A suitable control interface panel was fitted to the fixed station cabinet to receive commands from the control unit.
PTC400 Extension Controller
In the case of the PTC400 extension control units, either an internal microphone or an external telephone handset was used by the control operator. A multi-way cable interconnected the control unit and the PTC255 single-operator extension control panel, or the PTC265 double-operator extension control panel.
PTC401 Remote Controller
The PTC401 remote control unit was constructed in a similar manner to the PTC400 above and could be used for simplex or duplex applications using a single telephone line, or a pair of lines in the case of duplex operation. A PTC256 telephone line interface panel containing switching relays and line matching transformers was fitted to the fixed station cabinet.
This second generation of control units and control panels were designed to work with the second generation PTC703/PTC704 15 Watt fixed stations or the higher power PTC300 100 Watt transmitter. As with the first generation equipments, extension control or remote control of both simplex or duplex fixed stations was possible. The operator control instrument was either a telephone handset or a separate desk-top stand microphone.
The desk-top control unit was constructed from thick Bakelite moulded panels bolted together, with a curved front cover of expanded aluminium gauze. This construction was borrowed from a Pye Ltd domestic receiver which was finished in a gold spray paint finish. Early examples of the PTC406/408 equipments were also finished in gold but later changed to dimenso blue. A gold finished example will be photographed shortly. See also the photographs of the PTC411 below which used the same mechanics.
An electrically improved version of the second generation PTC406/408 operator control units using miniature all-glass valves instead of the older International Octal valves. This series of controllers was in production from 1952 until about 1963.
The PTC455 was a simple and low cost radiotelephone extension controller constructed from a standard telephone handset and base which also contained a small loudspeaker. The PTC456 was the matching 19 inch extension control panel fitted into the fixed station transmitter-receiver cabinet. This arrangement was suitable for use where the distance between the operator control point and the radiotelephone equipment was not greater than 200 feet. The PTC455 was suitable for controlling the PTC703/PTC704, PTC714/PTC715 equipment.
Equipment type PTC455Z was a later version of the above suitable to operate with the PTC723, PTC753, and PTC8701/2, PTC2701/2, PTC8701/2 Ranger based fixed stations.
A wide range of variants of this simple telephone handset and base type controller was used until the early 1960s. The example illustrated above and at right is from the radio system for UAR in 1962.
This was a further development of the existing PTC411 & PTC457 remote control equipment and was available with either a telephone handset or a high quality Lustraphone desk microphone as the operator control instrument. The Lustraphone microphones were available with either a short or long stand. The equipment was suitable for either simplex or duplex (2 wire or 4 wire circuits) operation.
This is a version of the existing PTC411 & PTC457/8 remote control equipment which used the new Pye PTC4000 Series desk microphone instead of the Lustraphone models. From December 1958 the use of the Lustraphone desk microphones was discontinued and the new PTC4000 Pye stand microphones (universally known as the Tulip Mic) were supplied.
This change also applied to the following fixed stations when locally controlled; PTC351/2/3/4, PTC931, PTC723/4, PTC723/4YN (the PTC723 fixed station used the PTC330 and PTC331 transmitter units).
The PTC431 controller was designed to provide control of a VHF AM air-to-ground station where the transmitter and receiver were sited separately. Two pairs of telephone lines were used to connect to the VHF equipment which could be sited up to 15 miles from the control operator position.
Although this controller was specifically designed for use with the PTC3600 1 kWatt transmitter used in trans-Atlantic ground-to-air communication with aircraft in transit between Newfoundland and Ireland, it was also adapted for use with other systems where the TX and RX were sited separately.
The PTC957 remote control unit was designed to give operator control of the PTC790 60 Watt HF station over a distance of 15 - 20 miles. It provided send-receive switching, channel selection and modulating facilities over one telephone line, and with addition of a second line would also remotely control the receiver Beat Frequency Oscillator (BFO) to aid the reception of CW Morse code signals..
Although the long running PTC411 single fixed station controller was frequently modified for individual customer requirements, many other physical and electrical configurations were demanded by customers. This led to the creation of small desk-top (or rack-mounted) operator control panels, with much of the complex electronics (termed common equipment) separately located in a 19 inch rack cabinet.
The example shown is a custom single channel desk-top controller from the 1960s.
As radio communications systems evolved through the 1950s and 1960s, the need quickly developed for multi-channel operation and multi-operator control. The standard practice in the Radio Systems department at Pye Telecom was to design custom radio systems to satisfy the customer unique operational requirements and to create custom operator control desks or consoles for each one. Although designs were re-used and gradually become modularised, they could not be completely considered as standard products which could be quickly priced and quoted without time consuming design work. This practice resulted in a huge number of different equipment variants.
See example of an operator equipment desk and at right a desk-top console in use at a UK Fire and Ambulance Brigade in 1962.
For complex multi-channel or multi-operator systems, which often included telephone-radio interfaces, a separate 19 inch rack of equipment would house the power supplies, line interfaces, switching equipment, dialling and ring-tone equipment, amplifiers etc. This was termed The Common Equipment.
A long running series of single channel control units designed by a team led by Don Delanoy. The equipment came in two basic variants, one for remote control of a fixed station transmitter receiver and one for extension control. The operator control instrument could be the PTC4000 tulip mic, or a telephone handset.
The equipment was replaced by the PC1, PC2, PC3, and PC5 series in 1971.
The early 5-channel controller, which had limited up-grade flexibility due to the design of the Common Equipment.
See image at right of the equipment mounted in control desk consoles in use with the Dumbartonshire Police circa 1967.
This new design of 5-station radiotelephone controller was introduced in 1969 to enable multi-channel radio communications systems to be controlled using a standard product, rather than create a custom design or variation of a custom design for each major contract, as had been done in the past.
An essential difference from earlier designs was that additional channel control modules could be added at any time to both the control desk equipment and to the rack of Common Equipment with which it interfaced.
See image at right of the equipment in use with Surrey County Council Ambulance Service circa 1970.
The equipment design was replaced by the Mascot 50 in about 1973.
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