What
is MAP?
MAP stands for Minimum
Advertised Price. PS Engineering, Inc. implemented this marketing program in
1998. This is the price that can be displayed in our dealers advertisement.
Back to top
I have already talked to a technician at PS Engineering, and he advised me send my unit to the factory. What information should I include in the box?
The following is a list of recommendations for use when sending
a unit back to PS Engineering for service:
-
You must obtain a Return Material Authorization (RMA) before returning
any product to the company.
-
DO NOT SEND VIA US MAIL. Use a shipping service such
as UPS or FedEx. These carriers offer insurance and reliable tracking
of your unit in case it is lost or damaged. PS Engineering is not liable for
lost shipments to the company.
-
Please include in the box your name, phone number and your RMA
number.
-
You may optionally include your credit card number and expiration
date in the letter. This only applies if we are performing
out-of-warranty work, or if you would like your unit returned to you by
overnight express shipping.
-
Make sure to send your unit to the following address.
Back to top
Since
I installed my new audio panel with my Bose® headsets I notice a whine in the
headset.
Airplanes
are noisy places. The addition of a good quality intercom, and active noise
canceling headsets does wonders for removing mechanical (wind, engine, etc.)
noise. It also allows us to hear electrical noise that used to be masked by the
mechanical noise.
However,
if properly installed with a nominal electrical system, PS Engineering audio
systems should reject most of the electrical noise, for a fairly quiet headset
environment.
The
MOST important part of any intercom is the installation. No intercom can work
well if not properly wired. Because of the amount of power PS Engineering
systems put in the headphones, we need to have shielded wires, which are
properly terminated. If not properly shielded, and isolated from airframe
ground, the audio signals can fall prey to the large noise signals present in
the airframe itself. The noise signals happen to be in the audio range, so no
amount of filtering can adequately remove them without loss of fidelity.
In
addition to shielding, it is vital to keep the intercom wiring away from the
really big wires for the alternator and power distribution. These are sources of
noise, as are strobe power supplies, panel lamp dimmer systems, autopilot
servos, blowers, and even antenna cables.
Installation
is so important. That's why we recommend a professional
installation, and or using a custom- made harness from PS Engineering.
One
issue specifically affects the Bose® installation. For best results, the Bose
panel power supply must be grounded to the same place as the intercom/audio
panel. This prevents airframe electrical noise from entering the system.
Finally,
it is important to realize that while intercoms have improved markedly in the
last 30 years, the old Microline or ARC avionics systems have not. Adding a high
quality intercom will improve the cockpit communications, but we can't change
the fact that your microphone is still transmitting over an old radio, and you
are still listening to a very faithful reproduction of the receiver signals from
that radio. There is no magic in the intercom to make that old AM radio into a
surround sound system.
Back to top
Since
my intercom was installed I can't hear myself when I transmit over the radio.
This is an issue of sidetone. Sidetone is the part
of the microphone signal that is sent back to your headset so you can hear
yourself talking. It's important that you get these audio cues so you know you
ARE talking, and loud enough.
During
radio transmissions, sidetone is created by the com radios, and serves to verify
that everything is working. So while you are transmitting, the intercom is
turned off and you are hearing what the aircraft radio is providing. Anyone who
can hear the radios on the intercom will also hear the sidetone.
Sometimes, the com radio does not produce sidetone This is particularly true with ARC
(Cessna) radios.
In
these cases, the intercom or audio panel can be modified by an avionics shop to
create an artificial sidetone in the intercom. This modification allows the
intercom to continue to operate during radio transmissions, so what you are
hearing is the intercom, not the radio.
In
other cases, sidetone can be lost because of installation problems. This occurs
when Radio Frequency Interference (RFI) enters the intercom wiring during
transmit, and cancels the sidetone. We have found this is caused by incorrect
jack wiring, usually because of grounding of the microphone jacks at the jack
end to the airframe.
The
ONLY place the jacks should be grounded is the intercom.
Back to top
Can
I use a mono headset in my stereo intercom?
You will nott hurt our stereo intercoms (PM3000)
or audio panels when you use a mono (1-channel) headset. The mono headset WILL
ground out the left side of the audio. In the pilot or copilot positions, nobody
will notice. Audio will be present in both ears.
However, optimal performance will not be achieved due to the fact that one
audio channel will no longer be heard and it is possible some additional white
noise will be heard.
In
any passenger position, plugging a mono headset will force any other stereo
headset to become mono, too. Those stereo headsets will only her in one ear,
unless they switch to the mono mode.
Back to top
How
do I get music in my intercom?
All PS Engineering intercoms and audio panels
support an entertainment input. When they are installed, the avionics shop
should add a small (1/8") stereo jack to the airplane. If it hasn't been
installed, the avionics shop can add one easily (depending on how difficult it
is to get to the intercom). This is hard-wired into the intercom's main
connector.
You
can use a portable stereo tape or CD player to play music through this jack. If
your intercom is monaural (PM1000-Series, PM501),
you will not have stereo separation. When installing the music jack in mono
installations, a stereo music jack should be used and the left and right
channels shorted together at the jack.
One
word of caution. PS Engineering cannot control the quality of portable devices.
We have had personal experience with portable CD players radiating signals that
interfere with VHF Com. Please be sure any portable music devises or built in
automotive types, are completely OFF during take off-approach and landing, or
any time communications are important. If you experience ANY navigation or
communication anomalies, switch off the entertainment source.
Back to top
My
music isn't loud enough.
There are a wide variety of voltage output from portable players.
They are designed for personal use, not for a
standard interface. We've seen that the type that uses 4 AA
batteries is louder than just 2.
This
inconsistency is one reason we created the PCD7100-P
Compact Disc player. Using our player assures the best performance possible,
with any intercom or audio panel.
Another
problem we've seen many times is the use of wrong cables from the player to
the intercom. All cables are not created equal, even if the plugs fit.
Some
adapter cables, used on camcorders, actually attenuate, or reduce, the amount of
signal between the player and intercom. They don't have much to start with,
and don't have any to spare. Be sure to get a "non-attenuating" cable.
Finally,
when using a portable device, be sure to use the normal headset output, and
expect to have the volume control at the loudest setting.
Back to top
Can
I use my 200W AIWA Car Stereo?
Sure. Just don't hook the speaker output directly
to the intercom. It will fail.
The
PS Engineering intercoms are designed to accept a low-level ( less than 3 V P-P)
audio signal, like the ones provided by portable devises. Car
stereo headphone amplifiers are not referenced to ground, and our intercoms are,
so the moment power is turned on, the output amplifier will try its darndest to
find ground, even if it has to let the smoke out of components.
We
recommend using a "Line Level" output from the car stereo. This is the one
usually used for power amplifiers, equalizers and other add-ons. Again, the
signals on this line vary widely between the brands and model.
IF
your automotive stereo does not have a "line out" there is an adapter
available from Crutchfield . Called the
PowerLinkII (PL2) this connects between the stereo and the intercom. It provides
the proper levels and can be adjusted to suit your needs.
Naturally,
the ideal solution is our
PCD7100, which is
FAA-approved and designed to work in airplanes.
Back to top
Why
should install the auxiliary mic and headphone jacks.?
At PS Engineering we've committed to value,
utility and safety. Although all of our systems have a fail-safe mode, the
intercom must still be in the aircraft to use the radios.
In
many cases, if you are retrofitting an intercom into a typical aircraft, these
jacks are already there. These are where the existing headset was connected.
The
additional jacks, which we call "auxiliary," serve several purposes. First,
they allow you to easily install a new intercom, because these
auxiliary mic and headphone are wired
straight to the aircraft radio's jacks.
Second,
they are a great troubleshooting tool. Suspect an intercom problem? Just move
the headset to the aux jacks, if the problem remains, it isn't in the
intercom.
Third,
they are the only way you can use the radios if you remove the intercom for any
reason. Since the intercom between the headset and the radios, when it is
unplugged, the pilot and copilot jacks are disconnected, too.
Back to top
The
music in my system won't mute when there is radio conversation.
Sometimes it pays to read the manual, but okay,
that's why we're here. On the PM3000 (and the
PM2000), the SoftMute™ is selectable for the main music source (Entertainment
1). Pushing the squelch knob activates and deactivates the SoftMute™.
On
the
PMA7000B the ICS pus button acts as the SoftMute control. For the
PMA8000B,
the Mute button selects the mute mode for the pilot and copilot. It is also
possible to have the installing party to configure the AUX pushbutton to act as
the SoftMute™ for the passengers. See the installation manual for details.
Back to top
Can
I install a non-TSO'd unit in my certified airplane?
Maybe.
Approval is determined by your PS Engineering dealer who will work directly
their local FAA
FSDO. When a part is not approved by the TSO, PMA, or STC process,
the part is unapproved. Only can the FAA can approve a non-approved part for
installation in a certified aircraft.
We suggest that your shop completes a Form 337 and have it approved BEFORE
installation begins.
PS Engineering strongly recommends the installation of only TSO'd units into certified aircraft.
Back to top
When the pilot pushes his PTT, there is carrier but no modulation. What is the
most common cause of this?
(Please
note this answer only applies to stand alone Intercoms.)
The most common cause of this problem is that the installer failed to
provide independent PTT wires to the Pilot and Copilot mic jacks. (Additionally,
it is highly probable they also failed to install the required AUX Mic and AUX
Headphone jacks, see FAQ #23).
There is a voting
system in the intercoms, and if the pilot's PTT is not hooked up to the Pilot's
Mic jack, and if the copilot's PTT is not hooked up to the Copilot's Mic jack,
the appropriate mic audio will not get through to the aircraft radio..
Back to top
My digital recorder only plays back for a few seconds. What could the problem be?
This problem could occur under either of the following conditions:
-
The radio input audio is to low to trigger
the digital recorder. Try increasing the volume on your radio and then
check the digital recorder operation again.
-
During the playback of a message, if the
playback button is held down for more than a few seconds, the digital
recorder will activate it's auto shutdown feature. You only need to
push the button once for the recorder to begin playing the last recorded
message. Holding the button is not necessary to continue
playback.
Back to top
What is
the difference between "Audio Low" and "Ground" when wiring
an intercom or audio panel?
When designing our audio products, our engineers used best practices when
it comes to eliminating as much electrical noise as possible. Our design
technique keeps "power ground", "digital ground", and
"signal ground" isolated until they are brought together at one
point. While an ohm meter might say all these grounds are the same, an
impedance analyzer would tell you different.
"Audio Low" is the
"signal ground" of the circuit. This terminology is
used throughout our harness schematics. It is not power ground and
therefore, should never use a conductor that could be used for power ground.
(Airframes are commonly used for power ground). This is why we don't use
single conductor shielded cable but rather, use a separate conductor in
the shielded cable as an "audio low".
Strict adherence must be
made to the wiring schematic to assure the best performance of our products.
Back to top
How would I wire a military
plug to be compatible with your system? (i.e. a single jack only 4 conductors vs.
two jacks used for the individual mic and headphone audio wires)
These jacks are compatible with PS Engineering systems. These are MONO jacks
so while all of our intercom and audio panels will work with this plug, the
system will be forced to be monaural. What's missing is the radio Push-to-Talk. This button is mounted on the control
stick in this sort of aircraft, and the button wired back to the mic cable to
take advantage of the shielding, if possible
This diagram shows the, mic audio high goes to pin 1, phones audio high goes to
pin 2, Mic low to 3, and phones low to 4.
You need to be sure that any headset or helmet equipped with such a plug uses
general aviation microphone (150 ohm) and headphone (150 to 600) impedance.
Military systems are often 8 ohm, and incompatible with civil aviation units.
Back to top
I have an audio
panels that has "SPLIT mode". I find when I transmit on one com the
other com gets static or goes blank, is this normal?
The problem you are describing is common. And it is important to know that it
is not the audio panel that is causing the problem, but rather allowing it to occur.
An explanation will help you understand what is going on.
The reason you are hearing this "bleed over" is because while one
radio is transmitting, the other radio is still receiving. In a non-SPLIT mode
capable audio panel, the audio panel inhibits the audio from the
non-transmitting receiver, thus eliminating any sound from getting to the
headset. But in SPLIT mode, the receiver is not inhibited in order to allow the
other person to continue to listen to their radio.
This problem is directly related
to the following:
1) Radio Frequencies; how close the two radios are tune too
2) Transmitter output power
3) Receiver selectivity
4) Antenna separation/location
You can see that there is nothing that can be done about 1 through 3. That
leaves number 4. To possibly reduce the problem is to place one of the
antennas on the belly of the aircraft. This will reduce the amount of radiated
power getting to the receive antenna.
Don't feel alone; pilots in corporate jets even have this problem to a degree.
However, they can get relatively close in frequency because they do have one
antenna on the belly AND the aircraft is much larger so they can get larger
separation.
Any dual audio panel system, even the ones in multi-million dollar aircraft, can
have this problem, it is physics. Some are worse than others because of the above
items 1, 2 and 3.
Back to top
I have had the PM1000II
installed for a few years now. It has worked flawlessly until
recently. The problem is I hardly hear my sidetone when I transmit.
What is probably causing the problem is RFI (Radio Frequency Interference). A
couple of things could have changed in your installation due to age,
vibration, or corrosion.
To trouble shoot the system, first turn off your intercom and then transmit
using the pilot headset.
If the problem still exists, then it is completely outside the intercom system
and you will need to take your aircraft to a qualified avionics shop for
evaluation.
If the sidetone returns to normal, then in all likely hood, the cause is too
much Radio Frequency energy is getting inside the intercom.
(NOTE: It is assumed that the wire
harness has been built to a PS Engineering specified wiring diagram and that
sidetone levels of the aircraft radio have been adjusted to the proper level.)
It could also be that one of the shields on the intercom harness has been broken
at the intercom connector or the SWR (Standing Wave Ratio) on your
antenna system has increased due to degeneration of the antenna coax (moisture
in the coax eventually breaks down the shielding), or more often, poor bonding
at the antenna also due to oxidation.
Our aircraft audio products use passive filtering (a device that consists of two
bead inductors and one capacitor). We have never had a failure of this device.
Back to top
My Motorola T720 hangs up
when I connect it into the PMA7000B
Place a 250K ohm resistor in the patch cord in-line (use a resistor small enough to
place inside the shell of the plug) with the microphone circuit (Tip) of the
cell phone.
Back to top
Products
