2
DHY-03 User Handbook
.
Remote port distributes the remote line connect switch and tally output, a
momentary/latch selector and the DTMF detect output.
.
The remote line connect switch can be either momentary or latching in its action.
.
Balanced mic/line input - 10k balanced input selectable for 0dBu clean feed line, or
microphone level with adjustable gain (line input only on DHY-03EC).
.
Divert relay (for new units, see page 40).
.
Balanced output - 0dBu low impedance balanced output, with output gain settings.
.
Record output - the conferencing output can be set via a jumper to give a mix
of the caller and mic/line input signals for recording both sides of the telephone
conversation (unavailable on DHY-03EC).
.
Line limiter, bandpass filter and output noise gate with preset threshold providing low
distortion audio.
.
Built in universal power supply between 90V AC and 250V AC, 47-63Hz, IEC
mains input (external DC required by DHY-03EC).
.
ETSI approval compliant with European PTT specifications.
What is a Telephone Hybrid ?
Telephone hybrids (or telephone balance units, TBUs) provide the interface between
professional audio equipment and the public telephone network. They provide protection
for your equipment and the public telephone lines, allowing for varying line signals and line
conditions. Automatically cancelling out the unwanted signal they also facilitate two-way
communication down a single telephone line, converting the two-wire telephone signal to a
four-wire send and return signal to be linked to a studio mixer, for example.
The hybrid has a telephone line connection and separate terminals for audio input and
output from a broadcast mixer, or other professional audio source.
A large proportion of Sonifex hybrids are used in radio and television broadcasting
applications for allowing external callers to be connected to the studio mixing console.
Most of the other units are supplied to communication operations for allowing extremely
effective conversion between four-wire audio circuits and standard telephone lines.
Built to a very high specification, the DHY-03 is simple to install and automatically adapts to
line conditions and programme content.
Available Formats
The DHY-03 digital telephone hybrids are available in four different formats. Three modules
have their own approved, integrated power supply and the DHY-03EC requires an external
DC supply:
INTR
ODUC
TION
INTRODUCTION
1