Tecpro beltpacks are tough, lightweight, remote intercom stations which are typically hung from the belt but can be used freestanding or mounted on a suitable surface. They offer full-duplex operation and have been designed for portable use where care may not always taken by the user. Series 2 beltpacks retain the robustness and simplicity of previous Tecpro designs while extending their performance to meet current operational requirements. They are compatible with earlier designs of Tecpro equipment. Six versions are available, for communication on either single or dual circuits.
The beltpacks are designed to be used on a circuit powered with either a Tecpro power supply or a Tecpro Master Station, although they may also be used with intercom systems made by other manufacturers; please request a data sheet for compatibility details. Each beltpack is otherwise self-contained, requiring only a headset and a cable to connect to the intercom circuit. Headset earpieces are wired in mono; the headset is connected to a 4-pin male XLR connector. A range of headsets is offered, but any headset with a microphone of nominally 200 ohms impedance and earpieces of 8-4000 ohms impedance may be used. Each beltpack has a powerful headphone amplifier; the microphone amplifier incorporates a limiter to prevent distortion due to input overload.
Single circuit beltpacks allow the user to communicate on a single ‘party line’. A volume control adjusts the level in the headphones, the ‘Mic’ switch lets the user speak to the circuit. Dual circuit beltpacks offer simultaneous access to two separate intercom circuits; each circuit has its own volume control. Two ‘Mic’ select switches let the operator speak to either or both circuits. When talk-back from an operator is not required, one or both microphone circuits can be disabled by pressing a combination of buttons on the beltpack.
To catch the attention of operators who have removed their beltpack and headset, a call alert signal is sent by pressing the ‘Call’ button to trigger the call lights on all user stations on a chosen circuit. (This is achieved by a combination of an inaudible 20kHz tone and a DC signal. DC call signalling has been retained for compatibility with previous Tecpro designs).
When a call alert signal is received, the ‘Call’ button and the ‘Mic’ buttons flash brightly to attract attention, red and green respectively. On dual circuit beltpacks, the ‘Call’ button flashes along with the ‘Mic’ button associated with the circuit receiving the alert. For increased visibility, Series 2 beltpacks also have an LED on their base so the call alert may be seen from most angles. A ‘Call’ send/receive confidence tone is also heard in the headset. This may be muted by pressing a sequence of buttons on the beltpack.
Some models have a vibration mode, similar to that used in mobile phones. This is triggered when a call alert signal is received. The function can be disabled by pressing a combination of buttons on the beltpack.
The brightly illuminated ‘Mic’ select and ‘Call’ switches make for good visibility in well-lit areas. For blackout conditions with an audience present, a low-light mode may be selected which dims the green mic buttons and prevents the call light from flashing. This is initiated by pressing a combination of buttons on the beltpack.
When powered down, beltpacks default to their factory settings. If required, the last beltpack configuration can be recalled by holding down the appropriate button as DC power is applied.
All Series 2 beltpacks can send and receive ‘Remote Mic Kill’ signals. This mode is useful for keeping unnecessary noise and chatter to a minimum so that important commands are not missed. To initiate ‘Remote Mic Kill’, a combination of buttons must be pressed. On receipt of the resulting inaudible tone on circuit A or B, the other beltpacks will automatically respond by switching off the corresponding microphone if it is active (note that first generation Tecpro beltpacks use mechanical ‘Mic select’ switches so are unable to respond to the ‘Mic kill’ tone).
Series 2 beltpacks are constructed in high-impact ABS, reducing weight without compromising strength or hard-wearing properties. The matt-black finish minimises visibility in stage applications. While commonly referred to as ‘beltpacks’, they are more versatile. A ‘mushroom’ shaped moulding on the rear of the case mates with the latching swivel belt-clip included as standard, as well as a wide range of other options currently under development.
Connectors and controls are recessed into the upper and lower surfaces of the case, to prevent damage and accidental operation. The upper face has a call button and press-to-talk microphone switches, which glow green when activated. The latter ‘toggle’ on and off if operated momentarily or act as press-to-talk switches if pressed for a longer period. A screwdriver-accessed preset control sets the level of the user’s own voice in the headset. One or two (for dual-circuit types) rotary volume controls set the audio level of the conversation in the headset. The base has the three connectors for headset and intercom circuits and a red LED which mimics the actions of the call indicator on the upper surface.