PS Engineering PM1000 (11909) - Manual (Page 4)

PM1000II Specialty Intercom Manual Page 4 Sept. 2007
shafts and secure, using the two # 4-40
round head screws provided.
4. Install the knobs over the volume and
squelch control shafts.
5.
2.2 Cable harness wiring
To complete the installation, a wire harness
must be made as shown in Appendix D.
PS Engineering can make a custom-tailored
wiring harness for the installer. All harnesses use
Mil-spec quality components with professional
techniques, and are fully tested before shipment.
Contact PS Engineering for more information.
If the aircraft already has pilot and copilot
headset jacks installed, you may re-use them.
Remove and discard all wires from the copilot
headset jacks. You may use the existing pilot
headset jacks as the Auxiliary Aircraft Radio
Headset Jacks, but they should be moved to a
new location to avoid confusion with the pilot's
headphone jacks. In the event the intercom has to
be removed for any reason, these jacks provide
access to the aircraft radio system.
To connect intercom into the aircraft audio
system, parallel the appropriate set of cables
from the intercom to the Auxiliary Aircraft
Radio Headset Jacks. Finally, install new
headset jacks into the aircraft and connect them
directly to the appropriate pins of the
PM1000II. See the wiring diagram for all
details of the wire harness interconnects.
2.2.1 Electrical Noise Issues
WARNING: You must use separate
shielded cables for the microphone and
headphone jacks. Combining these two wires
WILL cause loud oscillations and degrade the
intercom function. The oscillation is caused by
the cross-coupling between the large headphone
signal and the small microphone signal. The
resulting feedback is a high-pitched squeal that
varies with the volume controls.
Due to the variety of the radio equipment
found in today's general aviation aircraft, there
is the potential of both radiated and conducted
noise interference. The PM1000II has a
specially designed power supply to reduce
conducted electrical noise on the power bus of
the aircraft by at least 50dB. Although this is a
very large amount of attenuation, it does not
eliminate all noise when the amount is
excessive. There must be at least 12 Volts DC
present at the PM1000II for the power supply
to work within its designed regulation.
Otherwise, it will not be able to attenuate noise
properly.
Shielding can protect the system from
radiated noise (rotating beacon, electric gyros,
switching power supplies, etc.). However,
installation combinations can occur where
minor interference is possible. The PM1000II
NOTE: Auxiliary microphone and headset
jacks are required for a complete installation.
These provide troubleshooting and a back-up
access to the aircraft radios.
PM1000II Hole spacing (Not to scale)
Ø0.125 in
Ø0.265 in Ø0.375 in
Ø0.25 in
0.838 in
1.2 in
0.5 in
0.32 in
Sept. 2007 Page 7 200-125-0100
function to suit flight conditions. Regardless of
configuration, the pilot will always hear the
aircraft radio. NOTE: If there is a power failure
to the PM1000II, or if the power switch is
turned off, the copilot will not hear the aircraft
radio. Only the pilot is connected directly to the
aircraft radio.
ISO (Up Position): The pilot is isolated
from the intercom and is connected only to the
aircraft radios. He will hear the aircraft radio
reception (and sidetone during radio
transmissions). Copilot and passengers will hear
themselves and music but not the aircraft radio
traffic.
ALL (Middle position): All parties will
hear the aircraft radio, intercom, and music.
However, during any ICS or radio
communications, the music volume
automatically mutes. The music volume
increases gradually back to the original level
after communications have been completed.
3.5 PTT-ICS (11909 only)
The 11909 provides positive control over
the intercom through a separate intercom key
switch that is installed convenient to the pilot or
copilot. When this switch is open, no
microphone audio is passed to the intercom. For
best results, turn the intercom squelch fully
CCW and use the PTT-ICS switch to talk on the
intercom.
In many cases it is possible to revert to
VOX intercom if ambient noise is reduced (such
as during cruise). Place the PTT-ICS switch in
latched position (if equipped).
Section 4
Warranty and Service
4.1 Warranty
In order for the factory warranty to be valid, the
installations in a certified aircraft must be
accomplished by an FAA- certified avionics shop and
authorized PS Engineering dealer. If the unit is being
installed by a non-certified individual in an
experimental aircraft, a factory-made harness must be
used for the warranty to be valid.
PS Engineering, Inc. warrants this product to be
free from defect in material and workmanship for a
period of one year from the date of installation.
During this one year warranty period, PS
Engineering, Inc., at its option, will send a
replacement unit at our expense if the unit should be
determined to be defective after consultation with a
factory technician. The customer is responsible for
return shipment costs.
This warranty is not transferable. Any implied
warranties expire at the expiration date of this
warranty. PS Engineering SHALL NOT BE LIABLE
FOR INCIDENTAL OR CONSEQUENTIAL
DAMAGES. This warranty does not cover a defect
that has resulted from improper or unreasonable use
or maintenance as determined by us. This warranty is
void if there is any attempt to dissemble this product
without factory authorization. This warranty gives
you specific legal rights, and you may also have other
rights which may vary from state to state. Some states
do not allow the exclusion of limitation of incidental
or consequential damages, so the above limitation or
exclusions may not apply to you.
PM1000II, p/n 11909