ZETRON 4000 Series, Installation Manual

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Secondary Headset Jackbox
Considerations
To interface the TRHI to a telephone instrument, the telephone must already have an
operational headset port or jack. If this is not available, the signal levels and impedance
may not be compatible with the TRHI.
The telephone instrument must provide an off-hook signal to the TRHI to indicate that the
telephone is connected to a line. Absence of this signal greatly reduces the usefulness of
the TRHI and may cause undesirable audio levels at the headset earpiece. In any case,
some source of off-hook signal must be provided to switch the headset earpiece between
the telephone and the radio. If the signal is not available on the telephone, it can
sometimes be generated by an accessory headset jack adapter (available from the headset
supplier). It can also be generated by pressing a button on the radio console.
The preferred method of operation is pressing a telephone line connect button to generate
the off hook signal. This provides a single action for answering the line and for switching
the headset. Activating the “off hook” signal by other means usually requires one step to
switch the headset and another step to answer the line.
Generally, it is easier to interface to standard 1A2 key telephones than to electronic
telephones, especially Automatic Call Distributors (ACDs).
Zetron can supply headsets that are compatible with the TRHI.
TRHI Installation
Installation requires mounting the interface, selecting the interface operation through the
jumpers, wiring the interface to the telephone instrument, and wiring the interface to the
radio console.
For installation instructions, refer to the TRHI Product Manual (P/N 025-9553).
Secondary Headset Jackbox
The Series 4000 Secondary Headset Jackbox (SHJB) (Part # 950-9208) allows multiple
headsets to be connected to a console. The SHJB is low profile and is meant to be mounted
under the writing surface of a dispatch station. It is equipped with a dual-prong jack
(accepting either 4-wire or 6-wire plugs), and a volume control to adjust the earpiece
volume.
Note
Zetron does not support the use of amplified headsets with Series
4000 console equipment.