PS Engineering PM500EX Pilot’s Guide - Manual (Page 2)

202 - 118-0002 Page 2 PM501-Pilot Guide
Introduction
Congratulations on your purchase of a PM501 intercom! We at PS Engi-
neering welcome you to our family.
The PM501 is a panel mounted, 4-place intercom that offers a low cost al-
ternative for budget minded pilots who still want quality sound and per-
formance. This manual provides information on the operation of the
PM501. Please read it completely to maximize your enjoyment of its use.
Description
The PM501 is a 4-place intercom with individual output amplifiers for the
pilot, copilot, and passengers 1 & 2. The VOX (Voice Activated Squelch)
circuit prevents mic audio from getting through the intercom until someone
speaks. The volume control adjusts the level for all headsets and functions
as a PUSH-ON/PUSH-OFF power switch.
The PM501 has an automatic, fail-safe connection to the aircraft radio. In
the event that power to the intercom is lost, an internal relay will immedi-
ately connect the pilot's headset directly to the aircraft radio.
A provision for an entertainment input allows the pilot and passengers to
listen to music during flight. During intercom activity, this music automati-
cally mutes to allow communications without distraction. Note: the music is
NOT muted during radio reception.
The 2-position switch in the center is an intercom mode selector.
With the PM501, both the pilot and copilot have radio transmit capabilities.
Only the person who presses their Push To Talk (PTT) will be heard over
the aircraft radio. If both pilot and copilot press the PTT, the copilot will
override. The pilot regains priority by switching the unit off.
Specifications
Input power: 12-28 Volts DC
Current Drain: < 70 mA: Externally fused at 1 Amp
Headphone Impedance: 150-
1000 Ω Typical
Total audio power available: 225 mW
Aircraft Radio Impedance: 1000
Ω Typical
±3 dB Mic Frequency Response: 350 Hz-6000 Hz
±3 dB Music Frequency Response: 200 Hz - 15 kHz
Net weight: 8.5 Ounces (.340 kg)
Dimensions: 0.90" H X 2.60" W X 4.85" D
(2.2 cm x 6.6 cm x 12.3 cm)
Page 3 202-118-0002 PM501 Pilot Guide
OPERATING INSTRUCTIONS
Turn the PM501 on pressing the volume control knob (left knob). This also
engages the automatic fail-safe system.
Adjusting The Volume (1)
The volume control knob (1) adjusts the loudness of the intercom and music
for all headsets. Turning the control clockwise increases the audio. Many
headsets have volume controls on them. If it becomes necessary to reduce
the volume for an individual passenger, the three others should be set at
maximum, and the unit volume set for a comfortable level. The individual
can then reduce their volume accordingly.
The volume control on the PM501 does not have any affect the radio vol-
ume. This gives added flexibility for communications requirements. Vol-
ume control is also not affected by plugging in other headsets.
Adjusting The Squelch Control (2)
This VOX operated intercom keeps all microphone channels off while the
pilot, copilot or passengers are not speaking. This reduces background
noise from the aircraft. Only when someone speaks will their microphones
automatically turn on, passing the audio through the system.
Set the Squelch control knob (2) by slowly rotating the squelch
knob
clockwise until you no longer hear the engine noise in the earphones. When
the microphone is positioned properly near your lips, normal speech levels
should open the channel. When you stop talking, there is a delay of about a
second before the channel closes. This prevents closure between words and
eliminates choppy communications.
Mode Select (3)
The center switch (3) is a 2- position mode switch that allows the pilot to
tailor the intercom function to best meet the pilot's needs. Regardless of
configuration, the pilot will always hear the aircraft radio.
1
2
3