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Any reproduction or retransmittal of this publication, or any portion thereof, without the expressed written permission of Honeywell, Inc. is strictly prohibited. For further information contact the Publications Manager at Honeywell, Inc., 9800 Martel Road, Lenoir City, TN 37772. Phone (865) 988-9800, email avionics@ps-engineering.com.
Com 3) and six receivers (Nav 1, Nav 2, ADF, DME, MKR, and AUX). A duplex COM 3 mode (selectable at installation) allows the KMA 28B to act as an audio interface be- tween aircraft headphone and microphones and specific aircraft approved (FAA/FCC) cellular telephone equipment.
KMA 28B Audio Selector Panel and Intercom System Installation and Operator’s Manual An “Alternate Intercom Mode” is incorporated in KMA 28B. This allows the passengers and crew to con- verse, but removes radio traffic from the passengers’ headphones, and blocks passenger mics from the crew during radio receptions.
002-250-7028 Pilot’s Guide D201106000061 EQUIPMENT REQUIRED BUT NOT SUPPLIED Circuit Breaker: 1 ea; 3 amp PULL TYPE REQUIRED for KMA 28B Speaker, 4 Headphone Jacks (Stereo, as Required) Microphone Jacks (as Required) Headphones, 150 (Stereo), up to 6 as required Microphones, up to 6 as required Marker Antenna (75 MHz, VSWR <1:1.5, and appropriate for the airspeed)
Section 1.6 (B). If any claim is to be made, save the shipping mate- rial and contact the freight carrier. Do NOT return units damaged in shipping to Honeywell. If the unit or accessories show any sign of external shipping damage, contact Honeywell to arrange for a replacement.
Audio Panel Tray and Connector Assembly The unit connectors mate directly with the circuit boards in the KMA 28B. The connectors are a Molex crimp-type, and require the use of a Molex hand crimp tool, EDP P/N 11-01-0203, CR6115B (or equiv.).
There must be at least 13.8 VDC present at the bottom connector, pin 20, of the KMA 28B for the power supply to work in its designed regulation. Otherwise, it cannot adequately attenuate power line noise. Shielding can reduce or prevent radiated noise (i.e., beacon, electric gyros, switching power supplies, etc.) However, installation combinations can occur where inter-...
King Radio KX170-series, require a resistive load to prevent damage if their speaker amplifier is not used. Connect the speaker output from the unit to the load input on the KMA 28B (J1, pins 19 and L, 16 and M.
2.4.8 Backlighting The KMA 28B has an automatic dimming of the pushbutton annunciator LEDs and marker lamps con- trolled by a photocell. Control of the unit backlighting is through the aircraft avionics dimmer. Connect the dimmer control line to J1 pin D for 14 volt systems, and to J1 pin F for 28 volt systems. Pin E is light ground.
(Units with serial number beginning with (“J” or above) If an external switch is installed between pin 14 of the bottom connector and ground, the KMA 28B can be placed into “Alternate Intercom Mode.” In this mode, when the ICS is in “ALL” mode, the passengers will not hear aircraft radio.
2.4.14.1.2 Entertainment 2 Mute (Pin V) The ICS button on the KMA 28B controls the muting (“Karaoke mode”) of entertainment source #1. Connecting J2 pin V to ground through a SPST switch places the entertainment #2 music source into the Karaoke Mode.
The copilot hook switch is a SPST switch that connects pin L of J2 on the KMA 28B to ground to place the copilot mic audio on the Com 3 audio in duplex mode for cell phone operation.
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Installation and Operator’s Manual KMA 28B J2, pin M is the passenger hook switch. Install a SPST switch in a location adjacent to each passenger headset where cell phone use is desired. When pin M is connected to ground through any switch, the passenger microphones are all on the Com 3/duplex system.
Bendix/King KMA 28B Audio Selector Panel and Intercom System Installation and Operator’s Manual KMA 28B Pin assignments J2 Top Connector J1 Bottom Connector Chassis Ground Pilot Phone Audio Hi (Left) AUX Control Out MKR Coax Shield Copilot Phone Audio (Lt)
Unit Installation To install the KMA 28B, gently slide the unit into the mounting rack until the hold-down screw is en- gaged. While applying gentle pressure to the face of the unit, tighten the 3/32" hex-head in the center of the unit until it is secure.
Bendix/King KMA 28B Audio Selector Panel and Intercom System Installation and Operator’s Manual pilot has radio transmit capability in Com3 duplex mode, on the selected Com ( 1 or 2). However, he will have Com 3 capability if the copilot hook switch is grounded.
There are six pushbuttons associated with the communications transceivers. The lower buttons control which transceiver is selected for transmit. The KMA 28B gives priority to the pilot’s PTT. If the copilot it transmitting, and the pilot presses his PTT, the pilot’s microphone will be heard over the selected com transmitter.
Bendix/King KMA 28B Audio Selector Panel and Intercom System Installation and Operator’s Manual When switching from C 1 to C 2 while Com 2 has NOT been selected, Com 1 audio will be switched off. In essence, switching the mic selector will not effect the selection of Com receiver audio.
Split mode, particularly on adjacent frequencies. Honeywell makes no warranty about the suitability of Split Mode in all aircraft conditions. Note: Split Mode does not turn off other (Nav, ADF, etc.) selected audio to pilot. However, the copilot will only hear the selected communications receiver.
28B Stereo installation, one channel will be shorted. Although no damage to the unit will occur, all pas- sengers will lose one channel, unless they switch to the “MONO” mode on the headset. Honeywell modi- fies headsets to add stereo capability, using high-fidelity speakers. Contact factory for details.
3.6.3.1 Alternate Intercom Mode If an external switch is installed, the KMA 28B can be placed into “Alternate Intercom Mode.” In this mode, the passengers will not hear aircraft radio in the ALL intercom mode. In addition, the passengers’ microphones are not heard by the crew when the radios are active.
In ISO intercom mode, when the KMA 28B is in the Com 3 mode, the pilot position is in the "Phone Booth." Only the pilot will hear the telephone, and only he will be heard. He will also have access to Com 1 or 2, and will transmit on that radio using the PTT.
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Bendix/King KMA 28B Audio Selector Panel and Intercom System Installation and Operator’s Manual The Amber lamp, labeled "M," is the Middle Marker lamp and is coupled with a 1300 Hertz tone. It is keyed alternately with short 'dot' and long 'dash' bursts at 95 combinations per minute.
Bendix/King KMA 28B Audio Selector Panel and Intercom System Installation and Operator’s Manual Appendix A – KMA 28B Installation Drawing 1.315 in Cutout size for front mount installation (33.4 mm) 6.31in (160.3 mm) 6.65 in (167 mm) Side View 0.60 in (15.25 mm) 1.31 in...
Bendix/King KMA 28B Audio Selector Panel and Intercom System Installation and Operator’s Manual Appendix B Bottom Connector Interconnect Bottom Connector, J1 Com 1 Audio Hi Communications Com 1 Lo Transceiver #1 Com 1 Mic Audio Hi Com 1 Mic Key...
One method of airworthiness approval is through an FAA Form 337, Major Repair and Alteration (Airframe, Power- plant, Propeller, or Appliance) In the case of the KMA 28B, you may use the following text as a guide. Installed audio selector and 6-place intercom, Honeywell KMA 28B, part number (X) in ( location ) at sta- tion .
Bendix/King KMA 28B Audio Selector Panel and Intercom System Installation and Operator’s Manual Appendix E RTCA DO160C (EUROCAE ED-14) Environmental Qualification Form Audio Selector Panel/Intercom/Marker Beacon Receiver Part Number: 7000( ) FAA TSO Number: C50c, C35d Class A, JTSO 2C35d and JTSO C50c Manufacturer: PS Engineering, Inc.