Specifications

Trunk Cards and Connections
90 025-9035AA
Configuring for DID Operation
Central Office (C.O.) DID Description
Phone company central offices provide a type of access called Selector Level DID (Direct
Inward Dial). It is normally higher cost than end-to-end. In the case of a DID trunk, the
telephone line represents a bank of sequential telephone numbers (for example 555-34XX
covers the 100 numbers from 555-3400 through 555-3499). When a caller dials one of the
numbers in a bank, the telephone switch serving the paging terminal sends, via pulses or
Touch Tone, the last two (up to seven) digits of the telephone number dialed down the wire
pair to the Model 2200 telephone trunk card. The terminal converts the digits into the
pager number. No prompt or greeting is issued to the caller for the pager number since the
pager digits are automatically sent by the telephone company. The result, paging access is
quicker on selector-level trunks than on plain end-to-end lines, since the customer does not
need to overdial.
When ordering your selector level service from the telephone company, contact the
Centralized Operations Group rather than the local area business office. The COG is better
equipped to handle complex signaling requirements. Be sure to request either “immediate
dial” or “wink start” service. “Delay dial” is not supported by the interface card.
DID Installation
♦ Installing a DID line
1. Confirm that the DID line has been ordered to out-pulse or DTMF the same
number of digits that the Terminal expects. The DID line must be Immediate Dial
Start or Wink Start. Delay Dial will not work.
2. Remove each trunk card from the Terminal and check that the matrix plug is in the
DID position for those trunks that should be set for DID (selector level). Refer to
Jumper Matrix Settings on page 87 for more details on the matrix plug.
3. You can test each DID line with a plain dial or DTMF telephone. Connect the
telephone right to the Tip-Ring pair. Lift the telephone handset and dial the last
digits of a pager number. Confirm that the front panel LOOP indicator lights when
you lift the handset (and pulses as the dial turns). Also, note that the incandescent
lamps on the trunk card glow steadily when the telephone is off hook (and blink
with the loop light).
4. Unplug the telephone set, and plug in the DID line. On a telephone connected to an
outside line, dial one of the seven-digit DID numbers. The Terminal should go
through the same sequence as in step 3.
5. If you hear a fast busy after dialing, or the call does not go through, the tip and ring
leads may be installed backwards. Reverse them and try step 4 again.
6. If incoming DID numbers do not match any pager numbers, the Terminal will
answer the call, generate busy tones or a whoop for a few seconds, and hang up.
Make sure that you are dialing a real pager number that you have set up. See the