PS Engineering PM3000 - Manual (Page 6)

Page 6 200-193-0004 Rev. 4, Aug. 2003
mode.
2.4.5 Passenger Volume Adjustment
The 6-place PM3000 (11932, 11934) has adjust-
ments for passenger volume control. These are
accessed through the left side of the unit (viewed
from the front). There is a separate volume con-
trol for the left and right channels. The left ad-
justment is toward the front, and clockwise ad-
justment reduces passenger volume.
2.4.6 Internal Recorder (11933, 11934
only)
If the PM3000 unit is a part number 11933 or
11934 there is an internal recorder built into the
unit. This stores the last 60 seconds of radio traf-
fic. Only the pilot’s position will hear the play-
back.
To use this function, a normally open (NO) mo-
mentary switch is connected to the 3.5 mm
mono jack on the side of the unit. A low-current
switch is recommended.
A radio signal of more than 1 VRMS is needed
to trigger the IRS. Therefore, if the IRS does not
seem to be recording, increase the aircraft radio
volume slightly.
2.4.7 Monaural installations
The PM3000 can be installed as a monaural in-
tercom. Connect the RIGHT channel to the
headsets (this contains failsafe audio). Do NOT
combine left and right headphone outputs.
2.4.8 External PTT hook-up
Part of the installation includes the installation
of PTT (Push-to-Talk) switches that allow radio
transmissions from pilot and copilot positions.
There are three configurations that can be used.
You must select the case that best fits your in-
stallation. NOTE: Only the person who presses
their PTT switch will be heard over the radio.
CASE I-The PTT is built into the pilot and copi-
lot yokes
Simply install the plugs from the headset into the
aircraft headphone jacks. Then use the yoke
mounted PTT to transmit. No other action is re-
quired.
CASE –II Built in PTT only on the pilot side
This configuration requires a modified external
PTT switch plugged into the copilot's mic jack.
(See Appendix A) When the copilot's PTT is de-
pressed, this activates an internal relay that
switches the mic audio to the aircraft radio from
the pilot to the copilot.
Case III -No built in PTT switch at all.
Two built-in PTT must be installed or two exter-
nal, modified PTT switches will be required for
both the pilot and copilot. Modifications to the
PTT may be required. (See Appendix A)
2.5 Post installation checkout
After wiring is complete, verify aircraft power is
ONLY on pin 13 of the connector, and airframe
ground on pin 1. Other voltages may be present
on the incoming mic lines. Wiring errors can
cause serious internal damage and void PS Engi-
neering's warranty.
1. Apply power to the aircraft and avionics.
2. Plug headsets into the pilot, copilot and
passenger positions.
3. Verify that the pilot position can transmit
and receive with the PM3000 in the OFF
position (left hand knob controls on/off
by push on-push off).
4. Push the volume knob to switch the
PM3000 on. Rotate the volume clock-
wise, about half way. Verify that the
Pwr/Xmt light comes on green. If the
LED is red, immediately switch off the
Page 7 200-193-0004 Rev. 4, Aug. 2003
avionics, and troubleshoot the PTT in-
stallation.
5. Verify that the pilot can transmit and
receive on the communications trans-
ceivers.
6. Verify proper intercom operation for
pilot, copilot and passengers. For more
information, consult Section 3.
7. Verify proper transmit and receive op-
eration on the copilot position, noting
that the copilot PTT switch allows
proper transmission.
8. Verify proper Intercom system opera-
tion in the ALL, ISO (and CREW in
part number 11932, 11934) modes.
9. Verify that the intercom system does
not adversely affect any other aircraft
system by systematically switching the
unit on and off, while monitoring the
other avionics and electrical equipment
on the aircraft.
Recorder Option:
Verify that the incoming radio signals are stored
and played back using the external switch in-
stalled
3. Section III OPERATION
With the installation is complete, turn the
PM3000 on by pushing the volume control. This
also engages the automatic fail-safe system. The
intercom volume control does not control the
volume of the aircraft radio, allowing an addi-
tional degree of aircraft radio listening flexibil-
ity.
Figure 2 PM3000 (11931, 11933) front panel
controls
Figure 3 PM3000 (11932, 11934) front panel
controls
3.1 Adjusting the Volume
The PM3000 volume control knob adjusts the
loudness of the intercom and music only. The
volume control on the PM3000 does not affect
the volume level of the aircraft radio. This al-
lows the aircraft radio and intercom volume to
be balanced independently. The volume control
affects the music level for the pilot and copilot
positions.
By turning the control clockwise, the audio level
will increase. The PM3000 has individual out-
put amplifiers for each headset in the system and
provides plenty of audio output power. NOTE:
Volume level will not change with the number
of headset installed.
Music # 2 passenger volume in CREW mode
(11932 and 11934) version is a fixed level, and
controlled locally by the headphone volume con-
trol or music device.
3.2 Adjusting the Squelch Con-
trol
This VOX operated intercom keeps all micro-