Clear-Com TW-47 - Manual (Page 11)

T W - 4 7 T W O - W A Y R A D I O I N T E R F A C E 1 - 3
The TW-47 should be connected to the intercom station nearest
to the person who will be operating the base-station radio. If the
unit is being connected directly to the main intercom station, it
should, if possible, be connected directly to a separate main
station output.
RF INTERFERENCE
To avoid RFI interference, make sure the base-station radio and
the TW-47 interface is well removed from the intercom station to
which it is connected (2 to 5 feet / .6 to 1.52 m). Make sure the
cable connecting the TW-47 to the main station is kept separate
from the other intercom cables.
CONNECTING THE TW-47 TO THE
BASE STATION RADIO
In order to accommodate the widest variety of 2-way radios, the
TW-47 is supplied with a 9-pin connector and wiring diagrams
for many two-way radios. (See “Wiring Cables for Specific Radio
Types” later in this manual.) This will allow you to make your
own custom-made cable for your particular radio. This connector
socket is labeled on the TW-47 back panel as TWO-WAY
RADIO.
The combination of internal jumpers, connector wiring and front
panel “Transmit” and “Receive” level controls assures correct level
matching to virtually any radio. A relay provides the required
“push-to-talk” transmitter “keying” of the radio. This relay is
activated when the “call signal” on the Clear-Com intercom
channel is detected. The relay contacts, in conjunction with the
custom-made cable, allow for correct transmitter keying to
virtually any type of radio. The illustration in Figure 1-2 is a
simplified schematic showing the DB-9 connections.