Telephone Balance Unit
The TC22 line-powered telephone balance unit provides a high degree
of separation between send and receive signals, enabling 4-wire communications systems to
interface with the telephone network. In telephone IFB applications, the high drive capacity
at the 4-wire output enables a presenter's earpiece to be connected directly to the unit
without an external amplifier.
- Isolated, full-duplex 4-wire interface to non-digital telephone direct exchange lines.
- The unit is line powered, requiring no battery or external power.
- Simple optimization of sidetone rejection with any country’s telephone system.
- LED's indicate "ring" and "off hook" conditions.
- Input level control with line-sensing limiter and limit indicator.
- High drive output with level control for direct feed to presenter’s earpiece, etc.
- Loop-through British & American line sockets provide universal connection to line and telephone set.
- Connection to the telephone set is maintained while the unit is in use.
- Small, rugged metal case with XLR3 male & female 4-wire connectors.
| 4-Wire Input |
| Input Impedance |
10k ohm, transformer coupled on XLR3F connector |
| Input Level Range |
-12dBU to +8dBU before limiting, with average line |
|
| 4-Wire Output |
| Output Impedance |
150 ohms, transformer coupled on XLR3M connector |
| Output Level Range |
-12dBU to +8dBU, for average line level |
| Sidetone Rejection |
30 to 40dB average, depending on line characteristics |
|
| 2-Wire |
| Off-Hook Voltage |
3V minimum |
| 2-Wire Connectors |
2 x RJ11 (American), 2 x BT 603A (British) |
|
| Physical |
| Dimensions |
W60mm H34mm D165mm |
| Weight |
350g |
| Finish |
Diecast metal with light grey finish |
