Specifications

Trunk Cards and Connections
84 025-9035AA
Software updates may be needed:
• the paging terminal software (ZPAGE) must be Version 310h0 or later;
• the ZbaseW application software must be Version 310J or later;
• and the Dual Trunk code must be Version 6F0 (2-way version) or later.
The oparam.cds file must be set up properly for Alarm Monitoring, especially parameter
1E with value 02 to dedicate End-to-End lines to this purpose; or parameter 18 (overdial)
for using DID lines for both regular paging and alarm dialing. If there is a direct hookup
between alarm dialer and trunk (hardwired), set up the line type as a Zetron Ring Box (so
dialer units get dialtone).
Refer to the 2000 Series Paging Terminals Operating and Programming Manual (Part No.
025-9034-001), the Alarm Monitoring section for more information on this feature.
Large RAM
Newer versions of the Dual Trunk have more RAM (Random Access Memory) than older
versions. This additional RAM is required for support of certain features where trunks are
used for both inbound and outbound calls, and for Alarm Monitoring.
If you have older dual trunks, contact Zetron regarding upgrading to obtain the larger
RAM capability.
4-Wire Audio E&M
Four-wire audio E&M is supported as an option on the 2000 Series. Four-wire audio E&M
is usually used to avoid audio problems (feedback, echo, loss, “ringing”, touchy hybrid
balance) that occur when 2-wire audio lines (standard phone lines) are connected together.
There are separate transmit and receive audio pairs to avoid these kinds of problems.
Another reason to use this interface is that some telephone companies may require it to
deliver DID service.
Each 702-9318 “Dual Trunk Interface, 4-wire audio E&M” option gives you two
telephone lines. These are essentially modified Dual Trunks with an option board on them.
The six wires for each trunk are brought out in two ways. On the option board, there are
two RJ-11 modular telephone jack connectors, one for each side of the Dual Trunk, which
bring out all of the lines. These can be used instead of the regular 50-pin backplane
connectors.
The “regular” telco connector, e.g., J19 for Slot 7 in a 2200, carries the two E&M signal
lines and the two signal lines (Tip and Ring) for the receive audio. On Model 2200
systems with newer backplanes, the Tip and Ring lines for the transmit audio signals come
out on connector J23. Model 2100s and older 2200s do not have this connector, so the RJ-
11 jacks must be used.