level in the line is not loud enough, increase the input level with the PROGRAM TRIM control
on the rear panel. Conversely, if there is still program heard on a channel when the its level is
all the way down, decrease the PROGRAM TRIM level. Any change in the PROGRAM TRIM
level control on the rear panel to adjust for one channel will necessitate adjustments on the
other channel to compensate.
NOTE: Do not force the controls past their stop points as this will damage them.
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TEST TONE: This toggle switch turns on a 440 Hz test tone which can be heard on either or
both channels when the PROGRAM SEND switch for that channel is in the OFF position. It
can be handy for identifying which intercom channel is which or for other test purposes. The
PROGRAM SEND LEVEL controls adjust the level of the test tone on each channel.
6
A+B LINK SWITCH and INDICATOR: This toggle switch links the audio for channels A and B
together. A yellow light indicates when the channels are linked. It can be useful to have both
channels linked for rehersals, but separated for performances.
7
INTERCOM LINE CONNECTOR and SWITCH: A single intercom line connector is located on
the front panel for convenience. It can be switched between channels A and B with the
associated toggle switch.
Rear Panel
8
PROGRAM INPUT: This 1/4 inch TRS jack accepts a balanced or unbalanced line-level
signal. This is typically a feed from a mixing console, an air feed from a studio to remote site
over a phone line, or an audio cue track. The input accepts levels up to +10 dBV. Send levels
to the individual channels are controlled with a combination of the PROGRAM TRIM level and
the PROGRAM SEND levels on the channels. This feed can be fed to either or both intercom
lines.
9
PROGRAM TRIM: This control adjusts the overall input level of the external program coming
into the PS-232. It is used with the PROGRAM SEND LEVEL controls to achieve desired
system program levels. Turn the control clockwise to increase the gain and counter-clockwise
to reduce it.
NOTE: Do not force this control past its stop points as this will damage it.
10 TERM. ON/OFF: These switches (one per channel) select whether the PS-232 will provide the
required 200 Ohm termination for each channel. These should
always
be on unless there are
other power supplies or terminated main stations in the system. If there are other possible
terminations in the system, all but one must be turned off.
11 INTERCOM LINE CONNECTORS: There are three 3-Pin male XLR jacks per channel, wired
in parallel, or looped through. All the stations in the system are ultimately connected to the
PS-232 through these jacks. Because intercom audio is bidirectional, they are neither inputs
nor outputs, but may be thought of as "ports." Pin 1 is connected to the shield and carries the
signal ground. Pin 2 carries the DC voltage that runs the remote stations. Pin 3 carries two
way audio and call signals.
12 AC POWER SUPPLY INPUT: Connects to AC with an IEC cable. The PS-232 will accept any
line voltage between 90 and 240 Volts AC @ 50-60 Hz. It will automatically adjust to the line
voltage. There is no need for a selector switch or an external fuse.
Power Distribution and Short Circuit Protection
The PS-232 is capable of delivering up to 2 amps peak of 30 Volt DC current to Clear-Com stations.
The 2 amps peak is available on channel A and 2 amps is available on channel B. Since the total ca-
pacity of the PS-232 is 2 amps peak, the combined current of both of the channels at once may not ex-
ceed this maximum. Short circuits and overloads on any channel will not damage the PS-232. It will
simply cut power off to either or both channels which exceed their maximum current or which cause the
Clear-Com PS-232 Power Supply
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