On-Air Key Systems

Generic (1A1/1A2) Key Systems provide an ideal means for selecting an analog telephone line for broadcast or recording. This direct analog connection, using hybrids available from a number of broadcast equipment manufacturers, eliminates the signal degradation which can result from the successive analog-digital and digital-analog conversions required when interfacing digital telephone systems to analog broadcast equipment.

Seeing the advantages of this direct analog connection, many broadcast engineers have chosen to retain Generic Key as a studio system when the administrative portion of the station converted to digital telephones. KSL (Salt Lake City), KGO (San Francisco) and CIUT (Toronto) are examples of stations which have made this choice, with technical support from WTT.

Smaller community and cable broadcasters can derive the same benefits by choosing Generic Key as the station telephone system. In this application, administrative stations can be equipped with productivity-enhancing features such as headsets and auto-dialers, as required. Ethnic cablecaster CPWA sought WTT's assistance when Bell Canada destandardized their rented 1A2 system in 1993; WTT replaced the ailing Bell equipment with a new, identical system. Toronto community station CKLN converted from digital telephones to a WTT 1A2 Key System in 1994, to improve their ability to place callers on-air.

Fund-Raising Systems

With the growth of public sector broadcasting, many radio stations are faced with the need for an annual listener support drive. Such projects typically require the installation of a separate bank of telephone lines, on a short-term basis, to handle the volume of pledge calls generated by such a campaign. Use of analog telephony in this application facilitates control of studio indicator lights (one per line) and audible signals (if all lights are lit) to give on-air programmers instant information on incoming pledges.

This signal control method has been used in conjunction with single-line analog telephones at CKLN for their fall FundFest since 1995. CJRT, Toronto's oldest listener-supported broadcaster, uses a WTT 1A2 Key System with auxiliary lights for their annual fund raising campaign.

Multi-Station Access

Network newsrooms often require large numbers of telephones, each with access to a common group of lines on which correspondents report news stories. Because it may take a reporter some time to set up a telephone connection from the part of the world that is his or her "beat" to the newsroom, it is important that such a connection, once established, not be broken. In this context, transferring calls from one phone to another via electronic key or PBX systems can be risky. Generic key allows a call to be "handed off" from one user to another without having to be placed on hold or transferred, thus eliminating this risk. While a similar technique can be used with some digital systems (albeit more clumsily), the number of simultaneous pickups allowable will typically be limited.

When the Canadian Broadcasting Corporation moved their English Network Radio Newsroom to Toronto's Broadcast Centre in 1992, they found that the building's Nortel Meridian PBX limited access to a given line to 30 pickups. For a newsroom requiring more than sixty telephones, this restriction was unacceptable. To bypass this problem, WTT installed a 1A2 Key System with 62 Logic-20 telephones accessing a common group of sixteen analog lines from the Meridian PBX. Similar arrangements are used in major network newsrooms in the United States.

Isolation Transformers

WTT maintains a stock of the MUK1A/QUK1A Repeating Coil, a 150/600:150/600 audio transformer equivalent to the Western Electric 111C. The transformer is supplied on a 1.75" KTU bracket, complete with screw-terminal strip, suitable for apparatus box or direct wall mounting. It is typically used for isolating broadcast equipment from leased lines, or long internal wiring runs. 105-type apparatus boxes are also available for multiple MUK1A/QUK1A installations.

Wiring Accessories

Telephone and broadcast installations share a common factor: large quantities of cabling which converge on a central location. Many broadcasters have found that telephone 66-type connecting blocks (punch blocks) and associated hardware are an ideal wiring management tool in the broadcast environment. Contact WTT for more information about telephone connecting hardware for audio applications.

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