Clear-Com HX System Frames - Manual (Page 39)

4.5 Wiring audio devices to the matrix frame
An external four-wire audio device can be directly connected to a port connector through the four
audio pins. If there is excessive noise on the lines between the device and the matrix, the device may
be electronically unbalanced with the rest of the system. The device must be isolated with external
isolation transformers.
The CALL SEND output can be connected to the CALL REC input to tell the system software that
this is a directly connected port.
EHX allows the changing of the audio output reference level between -24, -21, -18, -15, -12, -9, -6, -3,
0, +3, +6, +9, +12 and +14 dB.
With a +12dB output reference level, it is possible to drive a 200 - 400 Ohm headset directly with a
port output for such uses as direct IFB feed.
The EHX configuration software allows the changing of the audio input reference level between -12, -
9, -6, -3, 0, +3, +6, +9, +11 dB.
Figure 9: Direct matrix frame port connection
Clear-Com recommends the use of shielded cable.
Tip: The Eclipse HX Installation Guide gives complete details about wiring audio devices to the
matrix. The installation manual also discusses RJ-45 cables and other types of cable required for
system installation.
39 Eclipse HX-Median User Guide