2
1 What Is A Telephone Hybrid?
• Local and remote line hold switching - calls can be remotely switched
through a mixing console.
• Line hold/release button to control line hold circuit, illuminates to
indicate the status of the line and flashes to show ring status.
• DTMF tone recognition allowing a opto-isolated GPI output to be made
on receipt of selected DTMF tones, e.g. for starting a studio automation
recorder automatically to record a remote telephone interview.
• International operation with built-in configurable settings for each
country.
• Country selection allows the unit to provide line impedance and a
simulation circuit to match the country.
• RS232 serial port for remote control of the TBU & DTMF tone dialling.
• 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.
Figure 1-1: DHY-04 Front & Rear.
DHY-04 Single Freestanding Automatic Digital TBU
