PS Engineering PAC24 Specifiche Scaricare il pdf (Pagina 17)

PS Engineering

PAC24 Series Audio Selector Panel and Intercom System

Installation and Operator’s Manual

200-240-0010 Page 2-10 Rev. 25, Feb. 2015

Some avionics do not provide a separate audio low, and may introduce additional electrical noise into the

system. For best results, connect the audio low from the audio panel to the radio ground, using one conduc-

tor of the twisted-shielded cable.

2.4.6 Transmit Interlock

Some communications transceivers use a transmit-interlock system. To fully utilize the Split Mode feature,

this function must be disabled. Consult that manufacturer's installation manual.

2.4.7 "Swap" Mode

When a momentary, normally open, push-button switch is connected between pin U (14 V) or 18 (28V

lighting) on the unit connector and aircraft ground, the user can switch from Com 1 to 2 to 3 etc. by d e-

pressing this switch without having to change the mic selection. This yoke-mounted switch eliminates the

need to remove your hands from the controls to change transceivers.

NOTE: Swap mode is active if the proper DIP switch selection is made internally to the unit.

2.4.8 Backlighting

The PAC24 has an automatic dimming of the pushbutton annunciator LEDs and marker lamps controlled

by a photocell. Control of the unit backlighting is through the aircraft avionics dimmer. Connect the dim-

mer control line to J3 pin 18 for 14-volt systems, and to J3 pin U for 28-volt systems. Pin 17 is light

ground.

If an external dimmer control is not used, a constant low-level back light illumination can be established for

nighttime viewing. Pin 18 or U (depending on system voltage) must be tied to power (J3, pin 25) for the

back lighting system to work. The photocell mounted in the unit face will automatically adjust the intensity

of the push-button annunciator LEDs.

2.4.9 Unswitched inputs

J3, pin 10 is the unswitched input number 1 and J3 pin 14 is unswitched input 2. These inputs are presented

to the pilot and copilot regardless of the audio configuration, and will always mute the entertainment in-

puts. These 510Ω inputs can be used for altimeter DH audio, GPS waypoint audio, autopilot disconnect

tones, or any other critical audio signal.

NOTE: In installations where an expansion unit is NOT used, the passenger and copilot audio output is

paralleled (J1, pin b). Therefore, unswitched audio will be heard by the passenger(s). Use an expansion

unit, P/N 11616, or 11616R (remote) to isolate passenger audio from unswitched alert audio.

2.4.10 PA Mute (J3, Pin 8)

Pin 18 of J3 is a TTL logic output that is pulled low during PTT operation. This serves as an input to exter-

nal public address system to prevent feedback during transmissions.

2.4.11 Public Address (J3, Pin B)

When the Speaker mode switch is in the PA mode, and the pilot’s PTT is activated, his voice is heard over

the PA speaker output on J3, Pin B. The copilot can continue to use the selected com.

In a dual installation, both the pilot and copilot panels can be connected to separate PA Speakers, for in-

stance, one ramp hailer, and one public address speaker.

NOTE: Connecting two audio panels to a single speaker for cockpit and/or cabin address

can result in damage to the audio panel.

2.4.12 Intercom wiring

See Appendices for intercom connection configurations. It is critical to the proper operation of this system

to have this connector wiring made in accordance with these diagrams. Use 2- and 3-conductor, MIL-spec

cable as shown. Connect the shields at the audio panel end only, and tie to the audio low inputs as shown.

1 2 ... 12 13 14 15 16 17 18 19 20 21 22 ... 39 40

Commenti su questo manuale

Nessun commento

PS Engineering PAC24 Specifiche Pagina 17

Commenti su questo manuale

Prodotti e manuali riguardandi Sistemi di interfono PS Engineering PAC24