Clear-Com HX System Frames - Manual (Page 59)

Key to Figure 19: DB-9M interface I/O connector for CCI-22
Connector Description
A
Channel #1:
Pin 1 = Clear-Com / RTS
Pin 2 = Ground
Pin 3 = +30 VDC Power
Pin 4 = Audio
B
Channel #2:
Pin 6 = Clear-Com / RTS
Pin 7 = Ground
Pin 8 = + 30 VDC Power
Pin 9 = Audio
Table 15: Key to Figure 19: DB-9M interface I/O connector for CCI-22
Stations on Clear-Com analog partyline systems (such as Encore) connect to each other
with two-conductor shielded microphone cable.
One conductor carries the DC power (28 to 30 V) for that channel, while the other conductor
carries the duplex two-way intercom audio signal plus DC Call Light signaling for that
channel. The shield acts as common ground for both power and signal for the channel.
Powering the CCI-22 interface module
Power to the CCI-22 interface module channels is provided by the external partyline.
The power connection for each channel is the +30 VDC Power pin on the appropriate
DB-9M interface I/O connector on the rear-panel assembly. The CCI-22 channel is
essentially just another beltpack on the partyline.
The power pin has DC filtering circuitry that provides a high impedance for the audio such
that power can be received from a powered line or TW line, as is common with RTS
systems. For TW operation tie the AUDIO and POWER pins together.
Terminating the partyline channels
Each partyline channel requires exactly one termination circuit. The termination circuit is
usually built into the system component that provides the party line’s power. Connecting
more than one termination circuit to a party line will impair the sidetone null and degrade the
line’s audio quality.
Important note:
When a CCI-22 partyline channel is connected to a Clear-Com partyline, the Clear-
Com/RTS Select pin must be left floating.
Grounding this pin selects the RTS mode, which is incompatible with Clear-Com partylines.
59 Eclipse HX Matrix Frame Installation Guide