Hardware manual

Issue 8 Electra Elite
5 - 46 Installing Electronic Telephone Units
4.8 DID(4)-U( ) ETU
4.8.1 Description
The DID(4)-U( ) ETU is the interface for Direct Inward
Dialing lines and 2-way DID lines. This ETU provides a
maximum of four DID lines. Wink start, delay start,
immediate start, and second Dial Tone are
accommodated with this ETU. Dial Pulse and DTMF are
also supported. There are four built-in DTMF signal
detectors. Tip and Ring electrical fuses are provided to
comply with UL 1459 requirements.
Figure 5-26 DID(4)-U( ) ETU