C172 Avionics

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The information contained in this manual is for reference use only. If any

information contained herein conflicts with similar information contained in the

Airplane Flight Manual Supplement, the information in the Airplane Flight

Manual Supplement shall take precedence.

WARNING

Prior to export of this document, review for export license requirement is needed.

COPYRIGHT NOTICE

1998 - 2012 Honeywell International Inc.

All rights reserved.

Reproduction of this publication or any portion thereof by any means without the

express written permission of Honeywell International Inc. is prohibited. For

further information contact the Manager, Technical Publications; Honeywell

Business & General Aviation; One Technology Center; 23500 West 105th Street;

Olathe, Kansas 66061. Telephone: (913) 782-0400.

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Silver Crown Plus Pilots Guide

ATTENTION

The operation of the GPS Navigation, Multi-Function Display and/or Traffic

Information Services components of your particular Silver Crown Plus System

are covered in separate publications. Choose the publication pertaining to your

installation from the list below:

Description Publication Part NumberKMD 150 Multi-Function Display/GPS 006-18220-0000

KLN 94 GPS Navigation System 006-18207-0000

KLN 89B GPS Navigation System 006-08786-0000

KLN 90B GPS Navigation System 006-08772-0000

KMD 550/850 Traffic Addendum 006-18238-0000

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KMA 26

1

KMA 26

Audio Amplifier/Intercom/Marker Beacon ReceiverKMA 26 Operation

KMA 26 Control FunctionTransmitter and

Automatic Receiver

Selection

The Microphone Selector Switch isa rotary switch used to select thedesired transmitter for the cockpitmicrophones. The C1, C2, andC3 positions are for transmitting onthe Com 1, Com 2, and Com 3communications transceivers,respectively. The EMG (emergency)position is used to bypass the KMA26s audio amplifier and directlyconnects Com 1 to the pilotsmicrophone and headphones. Thisprovides a fail-safe method ofcommunication should the unit fail.The PA position may be selectedwhen the aircraft is configured with

the KMA 26 driving a dedicatedpassenger address speaker.

The KMA 26 has an Auto Comfeature which always providesautomatic headphone audio selectionto match the Com transmitter in use.Thus, you may change theMicrophone Selector Switch withouthaving to reselect the correspondingCom receiver button in order to hearthe receiver. For example, if C1 isselected on the Microphone SelectorSwitch, you will receive transmissionson Com 1 through headphones andalso transmit on Com 1 when you keythe mic. Notice that as you rotate theMicrophone Selector Switch from C1to C2 to C3, the bottom of therespective Audio Select Buttondisplays a green illumination to showthat the corresponding receiver has

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2

been selected. To add speaker audiosimply push the Speaker SelectSwitch (inner right knob) to the inposition. Pulling the switch to the out

position removes speaker audio.

Additional Receiver

Selection

In addition to the receiver selected bythe Auto Com feature describedabove, other receivers may beselected by pushing thecorresponding Audio Select Buttons.

Push button audio selection isavailable for three Communicationsreceivers (COM1, COM2, andCOM3), two Navigation receivers(NAV1 and NAV2), the internalMarker Beacon receiver (MKR), oneDME, one ADF, and one additionalauxiliary receiver (AUX). The AUXposition could be used, for example,

for a second DME or ADF. When areceivers audio is selected, the greenannunciator illuminates at the bottomof the button. Push the button again todeselect the receivers audio. Volumefor receivers is adjusted from theindividual receiver itself, not from theKMA 26. Note that some receiverssuch as DME and marker beacon

(MKR) may not have volumeadjustments available to the pilot butthese radios usually may be adjustedat a Honeywell Sales and ServiceCenter.

Monitor Function

With the Monitor (MONI button)function activated, if Com 1 is

selected on the Microphone SelectorSwitch then Com 2 audio isautomatically routed to the speaker.Likewise, if Com 2 is selected on theMicrophone Selector Switch thenCom 1 audio is routed to the speaker.

This feature may be used, forexample, if you are listening to ATCon Com 1 through the headphonesand wish to monitor ATIS information

from Com 2 in the backgroundthrough the speaker. With theMicrophone Selector Switch in theCom 1 position for ATCcommunications, pressing the MONIbutton routes Com 2 (tuned to ATIS)audio through the speaker. Pressingthe MONI button again will disablethe feature.

When the Monitor function isinitially selected, the greenannunciators in the MONI buttonand in the button for the Com beingmonitored flash for approximately fiveseconds. At the end of this time theMONI annunciation remains onsteady while the Com annunciationreturns to its previous state (usuallyoff). The Monitor function is onlyusable when Com 1 or Com 2 isselected on the Microphone SelectorSwitch.

Marker Beacon Receiver

The complete TSOd three-lightmarker beacon receiver built into theKMA 26 gives you an accurate visualand aural signal when you pass overa 75 MHz beacon. The blue, amber,and white lights on the faceplate, aswell as the audio tones, identify thebeacon type (outer, middle, orinner/airway marker, respectively).

The MKR Audio Select buttonmust be pushed so that the greenannunciator is illuminated for themarker beacon receiver to provide anaudio signal at beacon passage. Thetoggle switch on the upper left side onthe faceplate provides the choice oftwo receiver sensitivities. When theswitch is in the HI SENS (upper)

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KMA 26

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position the high sensitivity is selectedwhich permits you to hear the outermarker tone about a mile from themarker beacon transmitter. At this

point you may select the LO SENS(middle) position to temporarilysilence the tone. It will start to soundagain when you are closer to themarker, giving you a more preciseindication of its location. Many pilotschoose to leave the switch in the lowsensitivity position.

Holding the toggle switch in the

TEST position simply appliesvoltage to all three marker lamps inthe unit and any external markerlights. The TEST position is springloaded so that when the toggle switchis released it returns to the LOSENS position.

The photocell in the faceplateautomatically dims the marker lightsas well as the green annunciators inthe Audio Select Buttons for nightoperation.

When marker audio is heard, thepilot may momentarily push theMarker Mute Button, if desired, tosilence the marker audio while theaircraft is passing over this markerbeacon. The marker audio willautomatically be reset so that it will beheard when passing over the nextmarker beacon. The Marker MuteButton has no effect on the MarkerBeacon Lamps.

Intercom

The KMA 26 contains a very versatilebuilt-in six station intercom. Intercomoperation is normally installed to bevoice activated (VOX), where theintercom becomes activeautomatically when a crew member orpassenger begins to speak. It mayoptionally be installed for keyed

activation, where a separatemicrophone switch must be keyed toactivate the intercom.

In order to set the proper VOX

sensitivity, momentarily press andrelease the left inner knob when noone is speaking into theirmicrophones. The VOX sensitivityshould be set if a background hissingsound is heard in the headphones orif intercom communications areclipped, i.e. the first syllable is lostduring intercom operation. The VOX

sensitivity may need to be reset whenthere is a large change in the noiselevel in the cockpit or cabin. The VOXlevel should also be reset each timepower is applied to the KMA 26.

NOTE: To properly set the VOXsensitivity make sure that no one isspeaking into the microphone. Thepilot may wish to put the intercom in

the ALL position to ensure that thereis no microphone activity beforemomentarily pushing the left innerknob. In addition, make sure thatnone of the microphones are in aposition to pick up extraneous noisesuch as wind noise from an openwindow/vent or vibration from layingon an instrument panel or against a

window. It is highly recommended thatany unused headsets be unplugged.

The intercom has three modes:ALL, CREW, and PILOT, whichare selected with the toggle switch onthe lower left side of the faceplate. Inthe ALL position the pilot, copilotand passengers are all on the same

intercom loop and everyone hearsthe radios. In the CREW position thepilot and copilot are on one intercomloop and can hear the radios while thepassengers have their own dedicatedintercom and do not hear the radios.

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In the PILOT mode the pilot hearsthe radios but is isolated from theintercom while the copilot andpassengers are on the same intercom

loop and do not hear the radios.When either the ALL and CREWintercom modes are selected, thepilots and copilots intercom volumeis controlled by rotating the CrewIntercom Volume Knob (left innerknob) while the passengers volume iscontrolled by rotating the PassengerIntercom Volume Knob (left outer

knob). When the PILOT intercommode is selected, the copilots andpassengers volume is controlled withthe Passenger Intercom VolumeKnob. Remember, the volume knobson the KMA 26 control intercomvolume only, not the receiversvolume.

Auxiliary Music Inputs

The KMA 26 can accommodatetwo music inputs for the listeningenjoyment of crew and passengers.

The music input is muted quicklywhen radio communications arereceived and then gradually returns toits previous volume. The KMA 26 canalso be configured at the time ofinstallation to either have or not havethe music be muted by intercomconversation. Table 1 outlines musicinput operation during the three

intercom modes for a system havingtwo music inputs. If there is only onemusic source it is usually installed asmusic 1 but it may be wired as eithermusic 1 or music 2.

INTERCOMMODE PILOT HEARS COPILOTHEARS PASSENGERSHEARPILOT NO MUSIC MUSIC #1 MUSIC #1CREW MUSIC #2 MUSIC #2 MUSIC #1ALL MUSIC #1 MUSIC #1 MUSIC #1

Table 1. Intercom Mode

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KMA 28

5

KMA 28

Audio Amplifier/Intercom/Marker Beacon Receiver

KMA 28 Operation

KMA 28 Control Function

Receive Audio Selectors

Receiver audio is selectedthrough two momentary and sixlatched, pushbutton, backlit switches.

Com 1 and Com 2 are the momentaryswitches.Because the rotary microphone

selector switch controls whattransceiver is being heard, the Com land Com 2 push-buttons are of themomentary type and do not remain inwhen selected. This is also part of the"auto" function. You will always hearthe audio from the transceiver that isselected for transmit by the rotary micselector switch.

The users can identify whichreceivers are selected by noting whichof the green switch LEDs areilluminated. Push buttons labeled Nav1, Nav 2, DME, MKR (Marker), ADF,

AUX (auxiliary), and SPR (Speaker)are "latched" type switches. Whenone of these buttons is pressed, it willstay in the "in" position. Press theswitch again and it be in the "out"position and remove that receiverfrom the audio.

Key "click"

The KMA 28 is equipped with anelectronic "click" to provide additionalfeedback for button operation. Toactivate the key click, push and hold

BOTH COM 1 and COM 2 receiverbuttons for five seconds, and release.Repeat to defeat the click.

Speaker Amplifier

The "SPR" in the push-buttonsection stands for speaker. Thisswitch will place all selected audio onthe cockpit speaker when this switch

is selected.Public Address (PA) Function

The KMA 28 has a publicaddress capability when an optionalexternal PA switch is installed. Whenthis switch is put into the PA position,the pilot's microphone is placed on aspeaker output. The copilot cancontinue to use the selected Com

radio.When this PA function is installed

a separate cabin speaker (rather thanthe cockpit speaker) is usually utilizedto prevent feedback.

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Power Switch /Emergency

(EMG) Operation

Unit power is turned on and off bypushing the volume knob. In the off or"Emergency" position, the pilot isconnected directly to Com 1. Thisallows communication capabilityregardless of unit condition. Any timepower is removed or turned off, theaudio selector will be placed in theemergency mode.

The power switch also controlsthe audio selector panel functions,

intercom, and marker beaconreceiver. Unless the mic selector is inCom 3 mode, at least one of theselected audio LEDs will be on (Com1 or Com 2).

Microphone Selector

When the mic selector switch isin the Com 1 position, both pilot and

copilot will be connected to the Com ltransceiver. Only the person whopresses their Push To Talk (PTT), willbe heard over the aircraft radio.Turning the rotary switch to the Com 2position will place pilot and copilot onCom 2.

The KMA 28 gives priority to thepilot's PTT. If the copilot it

transmitting, and the pilot presses hisPTT, the pilot's microphone will beheard over the selected comtransmitter.

Turning the mic selector fullycounterclockwise places the pilot andcopilot on Com 3. Com 3 receiveaudio is automatically placed in theheadset (and speaker if selected).

Com 1 and/or Com 2 receiver audiocan be selected to monitor thosetransceivers.

The KMA 28 has an automaticselector mode. Audio from theselected transceiver is automatically

heard in the headsets and speaker.You can check this function byswitching from Com 1 to Com 2 andwatch the selected audio light on the

selector change from COM 1 to COM2. This ensures the pilot will alwayshear the audio from the transceiver heis transmitting on.

When transmitting, the COM 1 orCOM 2 LED in the KMA 28 audioselector will blink as a furtherindication of the selected transmitter.When switching the mic selector

rotary switch from Com 1 to Com 2,while Com 2 audio had been selected,Com 1 audio will continue to beheard. This eliminates the pilot havingto switch Com 1 audio back on, ifdesired. When switching from Com 1to Com 2 while Com 2 has NOT beenselected, Com 1 audio will beswitched off. In essence, switchingthe mic selector will not effect theselection of Com audio.

Swap Mode (Switch from Com 1 to

Com 2 remotely)

With an optional yoke mounted,momentary switch, the pilot canchange from the current Comtransceiver to the other by depressingthis switch. When "Swap Mode" is

active, an annunciator in the lowerright corner of the unit will illuminate,indicating that the mic selector switchposition is no longer current . Tocancel "Swap Mode," the pilot mayeither press the yoke mounted switchagain, or turn the mic selector switchto the Com that is active.

Split Mode

Turning the rotary switch to Com1/Com 2 places the KMA 28 into "SplitMode." This places the pilot on Com 1and the copilot on Com 2. An exampleof this useful feature is when the pilot

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KMA 28

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may want to talk to Air Traffic Control,while the copilot may be speaking toFlight Watch. Although this mode haslimitations (see below) we believe you

will find this to be a useful feature.Switching to Com 2/Com l willreverse the "Split Mode" radioselection. The pilot will be on Com 2and the copilot will be on Com 1.

NOTE: Due to the nature of VHFcommunications signals, and the sizeconstraints in general aviation aircraft,

it is probable that there will be somebleed-over in the Split mode,particularly on adjacent frequencies.In addition, if the Com radios in theinstallation utilize a "transmit interlock"system, the split mode may not workproperly unless the interlock feature isdisabled.

NOTE: Honeywell makes noexpressed or implied guaranteeregarding the suitability of Split Modein a given installation.

NOTE: Split Mode does not turn offother (Nav, ADF, etc.) selected audioto pilot. However, the copilot will onlyhear the selected communicationsreceiver and unswitched audio.

Split Mode ICS

In split mode, the pilot and copilotare isolated from each other on theintercom, simultaneously using theirrespective radios. Depressing the ICSbutton in Split Mode will activate VOXintercom between the pilot and copilotpositions. This permits

intercommunication when desiredbetween the crew. Pressing the ICSbutton again disables this crewintercom function.

Telephone Mode

The "TEL" position, fully CW onthe mic selector switch, is the pilot's"hook" switch. This is active only

when the system is interfaced to anappropriate approved system, such asthe AirCell system. Placing the micselector in TEL places the pilotmicrophone and headphones on thecellphone. The pilot PTT will switchthe pilot mic to the COM 1, and allowcontinued aircraft communications aswell.

NOTE: Placing the mic selectorswitch in the TEL position will disablepilot and copilot intercom, as theintercom circuit is transferred to thetelephone use. In crew or ISO mode,placing the switch in TEL moderemoves the passengers access tothe telephone.

If interface is desired with anothertype of wireless telecommunicationsunit, the aircraft owner can purchasean after-market interface cable. ByFederal Communications Commission(FCC) regulations, these can only beused on the ground in the UnitedStates.

Interface cables are available forspecific telephones. The following is apartial list of available interfacecables:Compatible Phones

Audiovox Series 5Motorola TeleTAC, DPC 550,DPC65-, Lite Series, Profile SeriesMotorola Elite, M70, M75, SC-725Motorola Bag Phones, Mobiles

NEC100 Series, 110, 120, 180, SportNEC 700 & 800 SeriesOKI 900/910, AT&T 3730/3710OKI 1150/1145, AT&T 3760Fujitsu PCXMitsubishi 4000, DiamondTel

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KMA 28

9

aircraft radio receptions or pilottransmissions.

ALL (Middle Position):All parties will

hear the aircraft radio and intercom.Crew will hear Entertainment 1,passengers will hear Entertainment 2.During any radio or intercomcommunications, the music volumeautomatically decreases. The musicvolume increases gradually back tothe original level aftercommunications have been

completed.

CREW Down Position):Pilot andcopilot are connected on one intercomchannel and have exclusive access tothe aircraft radios. They may also

listen to Entertainment 1. Passengerscan continue to communicate withthemselves without interrupting theCrew and also may listen toEntertainment 2.

Anytime the KMA 28 is in eitherthe Com 1/Com 2, Com 2/Com 1,("Split Mode"), the pilot and copilotintercom is controlled with the ICS

button. The passengers will maintainintercommunications, but never hearaircraft radios.

Mode Pilot Hears Copilot Hears Passenger Hears Telephone Comments

Isolate A/C RadiosPilot Sidetone(during radiotransmission)Entertainment #1is Muted

Popilot andpassengerintercomEntertainment #1

Passenger andCopilot intercomEntertainment #2

Phone BoothmodePilot hasexclusive use ofthe telephone.In TEL, Pilotconnected to

Com 1 for PTTTX and receive.

This modeallows the pilotto communicatewithout theothers botheredby theconversations.

Copilot andpassengers cancontinue tocommunicateand listen tomusic

All PilotCopilotA/C RadioPassengersEntertainment #1

CopilotPilotA/C RadioPassengersEntertainment #1

PassengersPilotCopilotA/C RadioEntertainment #2

All have accessto phone throughHook Switch.Pilot accessthrough TELswitch.All heartelephone audio.

This modeallows all onboard to hearradio receptionas well ascommunicate onthe intercom.Music and

intercom ismuted duringintercom andradiocommunications

Crew PilotCopilotA/C RadioEntertainment #1

CopilotPilotA/C RadioEntertainment #1

PassengersEntertainment #2

Pilot and Copilotdont havephone access,unless mic sel inTEL.Passengershave phonethrough HookSwitch,Passengers hearphone audio.

This modeallows the Pilotand Copilot toconcentrate onflying, while thepassengers cancommunicateamongstthemselves.

Table 2. Intercom Modes

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Entertainment Input

The audio selector panel hasprovisions for two separateentertainment input devices. They

operate independently in the KMA 28.The volume control does not affectmusic level.

While in the ISO (Isolate) mode,the copilot will hear Entertainment 1while the four passengers will hearEntertainment #2. The pilot will hearEntertainment 1 at a level mutedabout 95%. In normal operation,

whenever a person speaks, or if theaircraft radio becomes active, themusic will automatically mute andthen will gradually return to theoriginal listening level when theintercom or radio conversationceases.

When in the All mode, pilot andcopilot will hear Entertainment 1 inputwhile all passengers will hear theEntertainment 2 source. While in theCrew mode, pilot and copilot will hearentertainment input #1 while thepassengers may listen toentertainment input #2.

Soft Mute and Soft Mute inhibit

The Soft Mute feature assuresthat the aircraft radio transmissions

will not be missed due toentertainment playing. When there isradio reception or intercomconversation, the music level isdropped to a background level. Whenthe radio or intercom traffic ceases,the level gradually returns to normal.

The front panel ICS switchcontrols muting of entertainment

source #1. Pushing this button placesthe ICS in Karoake (or sing along)mode, which inhibits the soft mutefeature. This allows the music tocontinue uninterrupted by intercom orradio traffic when cockpit workload is

appropriate. Pushing the button againwill release the mute inhibit function.

The passenger music, source #2,can be placed in the Karaoke mode if

a remote switch is installed in theaircraft.

Marker Beacon Operation

The Marker Beacon Receiveruses visual and audio indicators toalert you when the aircraft passesover a 75 MHz transmitter. The audiofrom the Marker Beacon Receiver can

be heard by selecting the "MKR"push-button switch.A three-position switch is used to

set the receiver sensitivity and to testthe indicator lamps. Use "High"sensitivity initially. This allows you tohear the outer marker beacon about amile out. Then select the "Low"sensitivity to give you a more accuratelocation of the Marker. When usedonly for approach markers, manypilots choose to leave the switch inthe low sensitivity position.

The momentary down switchposition is labeled "T/M" (Test/Mute)and illuminates all three lampssimultaneously to assure they are inworking order.

The "T/M" position is also aMarker Beacon "Mute" function.Pushing this switch while receiving amarker beacon signal will cause theaudio to be temporarily silenced. Noaction is required to restore the audioin time for the next beacon.

Telephone Operation (if

equipped with approved

system)

Each intercom position has a"hook switch." The pilot's hook switchis the "TEL" mode on the mic selector,the others are individual switches

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KMA 28

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mounted adjacent to the headsetjacks.

When the intercom is in ALLmode, the pilot can speak on the

phone only if the mic selector switchis in TEL position. All intercompositions will hear the telephoneconversation. Anyone who places hisor her switch into the "offhook"position will also be heard on thephone. All will hear selected audio.Com 1 audio is automatically heard inthe headsets. The pilot will have

transmit capability on Com 1, simplyby using the PTT switch.In CREW mode, the pilot and

copilot may use the telephone, withtheir respective hook switch (the pilotselects TEL on the mic selector). Anypassenger who places their switchinto the offhook position will also haveaccess to the phone, and all four

passengers will hear theconversation.

In ISO intercom mode, when theKMA 28 is in the TEL mode, the pilot

position is in the "Phone Booth." Onlythe pilot will hear the telephone, andonly he will be heard. He will alsohave access to Com 1, and willtransmit on that radio using the PTT.

All selected audio is provided.In all cases, only the pilot (and

copilot in ALL or CREW) will hear thecellphone ring. At that time they can

chose to allow a passenger to takethe call, or answer the phone.

NOTE: Because the phone uses anintercom circuit, all stations on thatcircuit will lose intercom capabilitywhen it is in use.

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KMA 30

13

KMA 30

Audio Panel/Marker Beacon Receiver/Stereo

Intercom System With Bluetooth Connectivity

KMA 30 Operation

KMA 30 Controls

Power Switch (1) (EMG-Fail

Safe Operation)

The power switch controls allaudio selector panel functions,

intercom and marker beacon receiver.When the unit is turned off, either

by pressing the volume control, or ifthe breaker is pulled removing power,

the KMA 30 is in Fail-Safe mode. In

this mode, the pilots headset is

connected to COM 1 for transmit and

receive, and connected to unswitched

input #1 for priority audio alerts. The

fail safe audio will only be heard in theleft ear of a stereo headset.

Communications Transmit

(XMT) Selection (2)

To select COM 1 or COM 2 for

transmit, press the button on thebottom row, next to the XMT legend.

The bottom and top button indicators

light, showing that you will transmit

and receive on the selected radio.

The audio on the radio selected for

transmit cannot be deselected.

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Communications Receive

(RCV) Selection (3)

To listen to the other radio, pressthe upper button, in the RCV (receive)section. When a com is selected forreceive, it will stay selected untilmanually deselected, even if youselect, and then deselect itstransmitter.

Unless the audio panel is in splitmode, the KMA 30 gives priority to thepilots radio Push-To-Talk (PTT).

If the MONITOR function is

activated, the audio from this radio willbe muted when the primary radio(selected for transmit) is receiving asignal.

In TEL mode, the pilot isconnected to the cell phone, but stillhears the COM radios selected. The

radio PTT will switch the mic tothe selected com, and allowcontinued aircraft communications tocontinue. (See Telephone section.)

Audio Selector (4)

These buttons select theswitched navigation receivers. TheDME input (if present) is also sharedwith AUX. In SPLIT mode, only thepilot will hear selected navigationaudio.

Cockpit Speaker (5)

This switch will place all selectedaudio on the cockpit speaker whenthis switch is selected. In Split mode,the speaker carries the same audio as

the pilot.Depending on installation,important audio alerts such as radaraltimeter or autopilot disconnect willcome over the speaker even if it is notselected, while other unswitchedinputs, will only be present if the SPRbutton is selected.

Consult your professional

avionics installer for these importantconfigurationdetails.

Intercom Operation

IntelliVox VOX-Squelch

IntelliVox is a proprietaryintercom squelch control. Through theuse of digital processors, each

microphone is monitored, and opensinstantly when human speech isdetected. This results in seamlessconversations aboard the airplane forcrew and passengers, without syllableclipping or fatigue-inducing noise.

No adjustment of the IntelliVoxsquelch control is necessary. There isno field adjustment. The system is

designed to block continuous tones,therefore people humming or whistlingin monotone may be blocked after afew moments.

For consistent performance, anyheadset microphone must be placedwithin -inch of your lips, preferablyagainst them. It is important to havethe microphone element parallel to

your mouth, and not twisted inside thecover.

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NOTE:For optimum microphoneperformance, we recommend use of aMicrophone Muff Kit from Oregon

Aero (1-800-888-6910,www.oregonaero.com ). This will not

only optimize VOX performance, butwill improve the overall clarity of allyour communications. You shouldalso keep the microphone out of adirect wind. Moving your head throughan air stream may cause theIntelliVox to open momentarily. Thisis normal. The IntelliVox is designedto work with normal aircraft cabin

noise levels (70 dB and above).Therefore, it may not alwaysrecognize speech and clip syllables ina quiet area, such as in the hangar, orwithout the engine running. This isalso normal.

Intercom Volume Control (7)

The small volume control knob

adjusts the loudness of the intercomfor the pilot and copilot. It has noeffect on selected radio levels, musicinput levels or passengers' volumelevel.

The larger, outer volume controlknob controls intercom volume for thepassengers. It has no effect on radioor music levels.

Mono Headsets in StereoInstallation

The pilot and copilot positionswork with stereo or mono headsets. Ifa passengers monaural headset isplugged in to a KMA 30 Stereo

installation, one channel will beshorted and all passengers will loseone channel unless they switch to theMONO mode on the headset.

Intercom Modes (8)

The intercom has three modes,ISO, ALL and CRW. The descriptionof the intercom mode function is validonly when the unit is not in the "Split"mode. In split mode, the pilot andcopilot intercom is controlled with theMute button.

The ICS button cycles throughthe intercom modes, from top tobottom and then back up.

ISO: The pilot is isolated from theintercom and is connected only to theaircraft radio system. He hears theradios (and sidetone during radiotransmissions). The copilot andpassengers will hear the musicsources as configured by the audiopanel configuration Function keys.See Smart Function Keys subsectionfor more details.

While in ISO Mode, the pilot canelect to hear music #1. First, be surethat the ISO mode is selected. Thenpress and hold the TEL button, thenhold the ICS mode button for morethan one second. The ICS indicatorwill blink slowly to indicate music is

present in ISO.

ALL:All parties will hear the aircraftradio and intercom. Crew will hearMusic 1, passengers can hear Music1 or 2. The music mutes in

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accordance with the muting modeselected.

CRW: (Crew) Pilot and copilot are

connected on one intercom channeland have exclusive access to theaircraft radios. The passengers havetheir own intercom. The music that thecrew and passengers will hear isdetermined by the Smart FunctionKeys.

Marker Beacon Operation (9)

The Marker Beacon Receiveruses visual and audio indicators toalert you when the aircraft passes

over a Beacon transmitter.The Blue, Outer Marker lamp has

an associated 400-Hertz 'dash' tone.The lamp and tone will be keyed at arate of two tones/flashes per secondwhen the aircraft is in the range of theOuter Marker.

The Amber, Middle Marker lampis coupled with a 1300 Hertz tone,

keyed alternately with short 'dot' andlong 'dash' bursts at 95 combinationsper minute.

The White, Inner marker lamphas a 3000 Hertz 'dot' tone, and willbe keyed at a rate of six times persecond.

Marker Beacon Receiver audiocan be heard by selecting the "MKR"

pushbutton switch. There is a serviceadjustment located on the top of theunit, labeled MKR VOL, to adjust thevolume if desired.

The MKR button located next tothe indicator lights is used to set thereceiver sensitivity, to test theindicator lamps, and mute the markeraudio.

Pressing the MKR button for onesecond will cause the marker audio tomute. The next beacon received willre-activate the audio.

Holding the MKR button for onesecond also activates marker test,labeled "T/M" and illuminates all threelights simultaneously to confirm thelights (internal and external) areworking. Releasing the button returnsto the last sensitivity.

Split Mode

To activate the split mode, pushboth the COM 1 and COM 2 XMT(bottom) buttons at the same time. Allfour indicators will come on. In the

split mode, the pilot is on COM 1,while the copilot is on COM 2.

Select either of the com XMTbuttons to exit the split mode. It is notpossible to have the pilot on COM 2and copilot on COM 1 in split mode.

NOTE:Due to the nature of VHFcommunications signals, and the size

constraints in general aviation aircraft,it is probable that there will be somebleed-over in the Split mode,particularly on adjacent frequencies.Bendix/King makes no warranty about

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the suitability of Split Mode in allaircraft conditions.

Telephone (TEL) (10)

The TEL mode serves as a fullduplex interface and distribution fortelephone systems such as portablecellular phones with earpiece jacks or

Bluetooth connectivity. Pressing thebutton connects the telephone to theusers as follows:

In ALL intercom mode, all crewand passengers will be heard on thephone when they speak. COM andother selected radio audio is alsoheard in the headsets. If the pilot orcopilot pushes the radio PTT, their

mic will be transferred to the selectedCOM radio. The telephone party willnot hear ATC communications, andvice versa.

In CREW mode, only the pilotand copilot are connected to thetelephone. Passengers will not hearthe telephone. In ISO intercom mode,only the pilot will hear the telephone,

and only he will be heard. He will alsohave access to COM 1 or 2, and willtransmit on that radio using the PTT.Selected radio audio is provided tothe pilot.

In cases where the cellulartelephone provides sidetone, theaudio panels internal sidetone can beturned off, by holding the TEL and

ADF buttons for more than onesecond.

Warning: United States FCCRegulations contained in 47 CFR 22.925 contain prohibition on airborne

operation of cellular telephones.Cellular telephones installed in orcarried aboard airplanes, balloons orany other type of aircraft must not be

operated while such aircraft areairborne (not touching the ground).When any aircraft leaves the ground,all cellular telephones on board thataircraft must be turned off.

Utility Jack

The 2.5 millimeter (3/32) jack onthe front of the KMA 30 has threedistinct functions:

Cell phone input (wired) Advisory audio input Music input (wired)

Cellular Phone

When a cellular telephone isconnected to this jack using anadapter cord, the KMA 30 audio panelwill connect the intercom to the cell

phone when the TEL button ispressed (10). When the TEL mode isoff, the telephone ringer audio will beheard if it is present on thetelephones output (ringer may bemuted by radio and intercom).

Audio Advisory Input

The front jack can be used as apriority advisory input for auxiliary

systems such as a GPS terrainadvisory or portable traffic watchsystem. To prevent radio or intercomfrom muting this input, press theMute button until MUTE is off.

NOTE: The front jack is no substitutefor the certified installation of alertssuch as the GPS waypoint or autopilot

tones. These still must be hard wiredinto the back by your installer.

Smart Jack Function

When the KMA 30 has an audiosignal on music #1 from the rear

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connector, the front panel jackautomatically becomes a Priority

Advisory input, and is heard in thecrew headphones, and this input will

NOT be muted by radio or intercom.,if the Music 1 audio is actively playing.

Music Input

When used as a music input, thefront panel jack (and Bluetooth) musicare treated as Music #1. Using theMusic function button, it can bedistributed to all users, depending onthe intercom mode.

Smart Function Keys (SFK)

With voice feedback, theconfiguration process is self-directed.These functions are non-essential andnon-required. Note: annunciations willbe stopped by any audio received onthe com radio selected for transmit.

To use these function keys,

INTERCOM, MONITOR, and MUSIC press and hold the desired functionkey until the audio annunciation of themode begins. NOTE: Functions arenot available in the split mode.

There are three special functions.INTERCOM function is related to theintercom audio distribution, and allowsthe crew to mute passengersintercom feed when radios are active.

The MONITOR function mutesthe secondary communication radioaudio when the primary radio (the oneselected to transmission) is active.

TheMUSIC function controlshow music is distributed in yourairplane.

There are two music sourcesavailable to the KMA 30, in addition tothe Bluetooth stream. Music 1 input atthe rear connector) and Music 2 iswired into the rear connector).

The volume of the functionselection annunciations and recorder

playback can be adjusted through ahole on the top of the unit markedANN VOL.

INTERCOM Function

Function INTERCOM controls thedistribution of aircraft radio andpassenger intercom. In the StandardIntercom Function mode, aircraftradios are distributed to all, when theintercom is in the ALL mode. InCREW mode, only the pilot and

copilot positions will hear aircraftradios.

When in Alternate IntercomFunction, the passengers will NEVERhear aircraft radios, even in the ALLmode. In addition, when in the ALLintercom mode, passengers will beable to converse with the crew, unlessthe aircraft radio becomes active,

when the intercom audio from thepassengers to the pilot and copilot isstopped, so the crew can focus on theradio. Passengers will always be ableto talk to each other.

To activate this function, hold theTEL button until the audio announcesAlternate Intercom Function, whenactivated, or Standard Intercom

Function when deactivated. Thealternate mode is announced atpower up, unless the power onannouncement has been defeated.

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MONITOR Function

This function turns the MONITORFunction on and off. When theMonitor is on, the audio from the COMthat is selected for reception only(only top LED illuminated) will bemuted when the radio that is selected

to transmit becomes active.This function is useful if you are

copying weather from AWOS on COM2, but have clearance delivery tunedin on COM 1. With the monitor active,the AWOS audio will be silencedwhen clearance delivery starts tospeak.

To activate the Monitor Function

press and hold AUX. The audio willannounce Monitor On, whenactivated, and Monitor Off whendeactivated.

NOTE:This mode is NOTremembered through power cycles, toprevent inadvertent blocking ofdesired audio on the next trip.

Music Distribution Function

The Music Function has three

modes. To cycle Music distributionmodes, press and hold MUTE buttonuntil the annunciation starts. When Music Number One, All

Headsets is selected, Music 1(Bluetooth source, or rear

connector) will be distributed toall headsets and is independentof the intercom mode switch.Therefore, even in the CREW

mode, the passengers will hearMusic 1, although though theywill not hear the crew intercom orradios. This mode allows you touse a single in-flightentertainment source. The musicmuting follows the front panelMUTE mode.

When you press MUSIC

function again for a second, youllhear, Alternate MusicDistribution. In this mode, Music2 will be heard only when theintercom is in the CREW mode,and only the passengers will hearit. Music 1 (Bluetooth, Rear input,and Front Panel Jack) will beprovided to passengers headsetin ISO and ALL intercom modes.

Press again, and you will hearStandard Music Distribution. Inthis mode, Music 2 becomesactive, and will always bepresented to the passengers.Music 1 is only available to thepilot and copilot. The intercommode switch will not have anyaffect on the music distribution.Music 2 is always heard by thepassengers, and never heard bythe pilot and copilot. This mode isuseful if your passengers have adifferent interest in entertainmentor are watching a DVD, but donot want to be excluded from theintercom conversations.

Alternate Music distributionmodes are remembered ant poweroff, and announced at power on,unless the power on announcementhas been defeated.

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Power on announcement

If the Intercom or Music Distributionhas changed from the factory default,the configuration will be played when

the unit is powered up. To defeat thisannouncement, hold the TEL andAUX buttons for two seconds. Thefeature can be enabled using thesame sequence.

Music Muting (6)

There are two SoftMute mutingcircuits. The front panel "Mute" button

has four modes, and controls theMute function for Music 1, front panel,and Bluetooth.

The SoftMute circuit will cut themusic completely out whenever thereis conversation on the radio, theintercom, or both, depending on theMute mode selected. When thatconversation stops, the music returnsto the previous level comfortably, overa second or so.

The mute mode functions arecontrolled through sequential pushesof the Mute button, and include voiceannunciations of the mode selected. Mute On - music will mute with

either intercom or aircraft radio -MUTE button is LED lit. Voiceannunciation is "Mute on."

Radio Mute - Radio will mutemusic, but intercom will not mutemusic - MUTE LED is OFF.

Annunciation is "Radio mute." Intercom Mute - Radio will not

mute music, intercom will mutemusic - MUTE LED is OFF.

Annunciation is "Intercom mute." Mute Off - The Karaoke mode -

music will not mute exceptduring radio transmissions.-MUTE button LED is OFF.

Annunciation is "Mute off."

When the KMA 30 is turned on, italways begins in crew Mute onmode.

The passengers intercom also

has a SoftMute circuit. If thepassengers hear the radio, or talk onthe intercom, the music will mute. Ifthe audio panel is in CREW mode,then the radio reception will not affectthe passenger music.

If the passengers are listening tothe music 1 input or front panel input,their Karaoke Mode is controlled by

the front panel Mute button. If thepassengers are listening to the music2 input, their Karaoke Mode isactivated by an external switchinstalled either in the aircraft, orconnected to the AUX button logicoutput pin on the KMA 30. Consultyour installer for details.

Music 1 Volume

The music level is set at thefactory at a comfortable level. Werecommend adjusting theentertainment volume at the sources.However, the Music 1 volume can beadjusted from the front panel, ifdesired, by pressing SPR button.

NOTE:Increasing this music level canincrease the amount of aircraftelectrical system noise as well.

The Music 1 volume can beadjusted from the front panel, ifdesired, by pressing and holding theMusic Volume (SPR) key.

Press the MUSIC VOL (SPR) formore than one second, a tone will be

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heard indicating the volume level ischanging and the music volume willbegin to change. The volume willeither increase or decrease,

depending on the last action. Toreverse the volume change, releasethe MUSIC VOL (SPR) button, andpress and hold again, and the volumewill change. Continue to hold until thedesired level is reached.

NOTE:Since it is possible to turn thevolume completely off, you may need

to turn the volume up if you dont hearmusic when you expected to. It willtake about 12 seconds to go fromminimum to maximum volume.

Swap Mode (Switch from

COM 1 to COM 2 remotely)

The external swap button allowsyou to switch between the COM

transmitters without having to reachup to the audio panel, and is a handyway to switch to Ground Control whenexiting the runway. This optionalswitch is usually mounted on thecontrol yoke or a convenient place bythe pilot position. See your avionicsinstaller for more information.

Internal Recorder System

The Intercom Recording Systemis a continuous loop recorder, (last

message received will be the firstheard), the recorder has 45 secondsof recording time, or up to eightmessages. There are no buttons topress to start recording. The systemautomatically begins to record the

instant the radio selected for transmitbecomes active. Only the pilot andcopilot will hear the playback audio.

To play back the last recorded

message, you press and hold theCOM RCV pushbutton associatedwith the selected radio transmitter forabout one second.

The message must stop playingbefore accessing the prior message.To cancel the playback, press andhold the playback button for twoseconds. The next time the button is

pressed for one second, the nextearlier message will be heard. If theradio becomes active while amessage is playing, the messageplayback will stop. The new audio willnot be stored. Press play to restart themessage you were playing.

Messages are lost when adifferent radio is selected fortransmission. The playback will stopwhenever there is more incomingselected com audio, and the messagecan be replayed from the beginning.

NOTE: an external playback buttonmay also be installed in a convenientlocation. See your installer.

Public Address Function (if

enabled)

To enter PA mode, press both

the Mute and SPR buttons at thesame time.

The Mute and SPR LEDs willblink to indicate the audio panel is inPA mode. The copilot can continue touse the selected com while the pilot

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will be heard over the speaker. To exitpush Mute and SPR again. Thismode is also reset when power iscycled.

Backlighting

The white text backlighting iscontrolled by the aircraft dimmer,

while the green indication LEDs areautomatically controlled by the lightsensor on the KMA 30.

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KY 196A, KY 197A and KY 196B

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VHF Communications Transceivers

KY 196A, KY 197A and KY 196B Operation

KY 196A/197A

KY 196B

Power Up

When you turn theON/OFF/Volume knob clockwise to

the ON position, your unit willdisplay the frequencies last used inthe USE and STBY (standby)windows.

To override the automaticsquelch, pull the ON/OFF/Volume

knob out and, judging by static noise,rotate it to the desired volume level.Push the knob back in to activate theautomatic squelch.

NOTE:As with all avionics, the KY196A, KY 197A and KY 196B shouldbe turned on only after engine startup.This simple precaution will helpprotect the solid-state circuitry and

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extend the operating life of yourequipment.

Transmitting

During COMM transmissions, aT will appear between the USEand STBY windows to indicate thekeying of the microphone.

KY 196A/197A Frequency

Mode(Normal Operation)

1. Select a new frequency in theSTBY window, using the frequencyselection knobs. The larger knobcontrols changes in increments of1MHz. The smaller knob controlschanges in increments of 50kHz when

pushed in, and 25kHz when pulledout.

At the outside limits of the band, thedisplay will wrap around to the otherend of the band, going from 136MHzto118MHz.

2. Press the transfer button to activatethe new frequency. The newly enteredfrequency in the STBY window flip-flops with the frequency in the USEwindow. This new frequency is nowavailable for use. An optional remote-mounted frequency transfer buttonmay also be used to perform this flip-flop function.

KY 196B Frequency Mode

(Normal Operation)

1. Select a new frequency in theSTBY window, using the frequencyselection knobs. The larger knobcontrols changes in increments of1MHz. The smaller knob allowsselection of 25kHz frequencies onlywhen pushed in, and both 8.33kHz

and 25kHz frequencies when pulledout.

At the outside limits of the band, thedisplay will wrap around to the otherend of the band, going from 136MHzto 118MHz.

2. Press the transfer button to activatethe new frequency. The newly enteredfrequency in the STBY window flip-flops with the frequency in the USEwindow. This new frequency is nowavailable for use. An optional remote-mounted frequency transfer button

may also be used to perform this flip-flop function.

Program Mode

The Program Mode is used to

program frequencies for use in theChannel Mode.

1. Depress the channel (CHAN)button for more than two seconds,until the channel number (to the right

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of the standby frequency) beginsflashing. The most recently usedactive frequency will remain displayedin the USE window.

2. Turning either frequency selectionknob will change the channel.

3. Once youve selected the desiredchannel number, you may program anew frequency by pressing thetransfer button. This will cause thefrequency in the STBY window toflash. The tuning knobs are now usedto enter desired frequency.

4. To program additional channels,push the transfer button again tomake the channel number flash, andrepeat step three above.

5. If you with to program fewer thannine channels while skipping certainchannel numbers, rotate the MHZfrequency knob left or right beyond136MHz or 118MHz. Dashes (---) will

appear in the STBY window,indicating that the channel will beskipped when the system is operatingin the Channel Mode.

6. To exit the Program Mode,momentarily press the channel button.The unit will also automatically exitthe Program Mode if no programmingoccurs within approximately 20seconds.

The Program-Secure Mode

The Program Secure Mode maybe used to lock a desired frequency toa specific channel number, prohibitingprogram changes from the front of theunit. Your KY 196A, KY 197A or KY196B should be taken to yourBendix/King dealer for programmingin the Program Secure Mode.

Channel Mode

The Channel Mode is used torecall preset frequencies stored inmemory.

1. To enter the Channel Modemomentarily, push the channel buttonwhile in the Frequency Mode. Theactive frequency remains displayed inthe USE window, and the last usedchannel number and its associatedfrequency are displayed in theCHAN and STBY windows.

If no channels have beenprogrammed, channel 1 automatically

disappears and dashes are displayedin the STBY window.

2. Turn either frequency selectionknob to change the channel number

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and the channels correspondingfrequency in the STBY window.

3. If there is no activity for fiveseconds, the radio will exit theChannel Mode and return to theFrequency Mode, with the channelfrequency remaining in the STBYwindow.

4. You can also return to theFrequency Mode by either:

a. Pressing the channel button beforethe five-second delay, in which case

the radio recalls the USE andSTBY frequencies prior to enteringthe Channel Mode, or

b. Pressing the transfer button, so thatthe channel frequency becomes theactive frequency and the last USEfrequency becomes the new STBYfrequency.

NOTE: If the optional remote channelincrement switch is installed, eachactivation of the switch will put the unitin the Channel Mode and advance thechannel number from the previouschannel used.

Direct Tune Mode

The Direct Tune Mode is enteredby pressing and holding the transferbutton for longer than two seconds.The STBY frequency will disappearand the frequency in the active

window can be changed with thefrequency selection knobs.

Momentarily pushing the transferbutton will return the unit to theFrequency Mode (normal operation).The STBY frequency displayed priorto entering the Direct Tune Mode willreturn unchanged.

Default Mode

Turning on your KY 196A, KY197A or KY 196B while pressing thetransfer button will bring the unit up inthe Direct Tune Mode and install

120.00MHz or 120.000MHz (KY196B) as the active frequency. Thiswill aid the pilot in blind tuning theradio in the unlikely event of displayfailure.

Display Adjust Modes

To enter the Display AdjustMode, press and hold the channelbutton until the Program Mode isentered. Continue holding the channelbutton while simultaneously pressingand holding the frequency transferbutton until dA 1 replaces the

frequency in the USE window.

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The frequency selector knobs areused to change the value in theSTBY window. Momentarily pressingthe channel button steps the unit

through the Display Adjust Modes,dA 1 through dA 3. Press thefrequency transfer button to exit theDisplay Adjust Mode.

Display Adjust 1 (dA 1) is used tovary the dim/bright response time tochanges in ambient light on thedisplay photocell. The range of valuesfor dA 1 is 1-8, with 1 representing

normal.The normal setting, 1, providesimmediate display brightness changeswhen there are changes in the lightfalling on the photocell. With dA 1 setto a value of 8, the response time isapproximately eight seconds. dA 1values of 2 through 7 provideintermediate response times.

Display adjustment 2 (dA 2) isused to vary the display brightnesswhen ambient light conditions are lessthan direct sunlight, such as in a dark

cockpit. dA 2 values range from 0-64,with 0 being dimmest and 64 beingbrightest; the normal dA 2 setting is20.

dA 3 values range from 0 to 255,with 0 being dimmest and 255 beingbrightest. This adjustment varies theamount of ambient light required forthe display to reach its full dim and

bright levels. Normal dA 3 values for anew display range from 0 to 30.A common use of dA 3 is to

adjust the KY 196A, KY 197A or KY196B display brightness to match thebrightness of other radios displays.

Another use is to provide displaybrightness compensation as thedisplay ages.

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KX 155A/KX 165A

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KX 155A and KX 165A

VHF Communication/Navigation Transceivers

KX 155A and KX 165A Operation (25 kHz Versions)

All controls required to operate the KX 155A and KX 165A are located on the unitfront panel.

FIGURE 1A

KX 155A and KX 165A (25 kHz Versions) CONTROL FUNCTION

FIGURE 1B

KX 165A (8.33 kHz Versions) CONTROL FUNCTION

NOTE: The 25 kHz and 8.33 kHz versions of the KX 165A are distinguishable

from one another in two ways. The 25 kHz version has PULL 25K nomenclaturebelow the Comm Frequency Select Knobs while the 8.33 version has PULL8.33K. In addition, the 25 kHz version has two digits to the right of the decimal inthe Comm frequency while the 8.33 kHz version has three digits to the right ofthe decimal. The 8.33 kHz channel spacing is required for flight in certainEuropean (ICAO EUR Region) airspace.

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COMM Transceiver

Rotate the VOL knob clockwisefrom the OFF position. Pull the VOLknob out and adjust for desired

listening level. Push the VOL knobback in to actuate the automaticsquelch.

The left portion of the digitaldisplay readout is allocated for COMM

ACTIVE and COMM STANDBYfrequencies with a T between themto indicate TRANSMIT and an R toindicate RECEIVE modes of

operation.Select the desired operating

frequency in the standby display byrotating the Frequency Select Knobseither clockwise or counterclockwise.

A clockwise rotation will increment theprevious frequency while acounterclockwise rotation willdecrement the previous frequency.

The outer knob will change theMHz portion of the standby display. Atone band-edge (118 or 136 MHz) thefollowing 1 MHz change will wraparound to the other band-edge.

KX 155A and KX 165A 25 kHz

Versions

The inner knob will change the

kHz portion of the standby display. Itwill change in increments of 50 kHzwhen the knob is pushed in and 25kHz when the knob is pulled out. Thefrequency wrap around at the edge ofthe band is also utilized whenincrementing or decrementing the kHzportion of the standby display.

KX 165A 8.33 kHz Version

The inner knob will change thekHz portion of the standby display. Itallows selection of 25 kHz frequenciesonly when the knob is pushed in andboth 8.33 kHz and 25 kHz frequencies

when the knob is pulled out. Thefrequency wrap around at the edge ofthe band is also utilized whenincrementing or decrementing the kHz

portion of the standby display.To tune the radio to the desiredoperating frequency, the desiredfrequency must be entered into thestandby display (Figure 2) and thenthe transfer button must be pushed.This will trade the contents of theactive and standby displays (Figure3).

NOTE:An optional remote-mountedtransfer switch may also be installedin a convenient location (such as thecontrol yoke) to perform the transferoperation.

The operating frequency can alsobe entered by accessing the ACTIVEENTRY (direct tune) mode which isdone by pushing and holding theCOMM TRANSFER button for 2 ormore seconds. In the direct tunemode, only the active part of thedisplay is visible (Figure 4). Thedesired frequency can be directlyentered into the display. Push theCOMM TRANSFER button again toreturn to the active/standby display.

FIGURE 2

Frequency entered in

standby display

FIGURE 3

Active/standby frequencies toggle

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FIGURE 4

Frequency entered in active entry mode

The transceiver is always tunedto the frequency appearing in the

ACTIVE display. It is thereforepossible to have two differentfrequencies stored in the ACTIVE andSTANDBY displays and to changeback and forth between them at the

simple push of the transfer button.During the transmit mode of

operation, a T will appear betweenthe ACTIVE and STANDBY displays.

An R will appear between theACTIVE and STANDBY displays if adetected signal is strong enough toopen the squelch, signifying that thetransceiver is in the receive mode of

operation.A non-volatile memory stores thecomm ACTIVE and STANDBYfrequencies on power down. Whenthe unit is turned on again, the COMM

ACTIVE and STANDBY windows willdisplay the same ACTIVE andSTANDBY frequencies that weredisplayed before power down.

The KX 155A and KX 165A alsohave provisions to program 32channels. Pressing the CHAN buttonfor 2 or more seconds will cause theunit to enter the channel programmode. Upon entering the channelprogram mode, PG is displayed nextto the channel number and thechannel number will flash indicating

that it can be programmed (Figure 5).

FIGURE 5

Entering channel program mode

The desired channel can beselected by turning the comm kHzknob (Figure 6).

FIGURE 6Selecting desired channel

The channel frequency can beentered by pushing the COMMTRANSFER button which will causethe standby frequency to flash. Thecomm frequency knobs are then usedto enter the desired frequency

(Figure 7).

FIGURE 7

Selecting desired frequency

If dashes (displayed when

rotating the outer knob between 136MHz and 118 MHz) are enteredinstead of a frequency, thecorresponding channel is skipped inchannel selection mode (Figure 8).

FIGURE 8Corresponding channel is skipped in

channel selection mode

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Additional channels may beprogrammed by pressing the COMMTRANSFER button and using thesame procedure. To exit the program

mode and save the channelinformation, momentarily push theCHAN button. This will cause the unitto return to the previous frequencyentry mode. The unit will also exit thechannel program mode if there is nobutton or knob activity for 20seconds.The channel selection modecan then be entered by momentarily

pushing the CHAN button (Figure 9).

FIGURE 9

Entering channel selection mode

CH is displayed next to the last

used channel number.NOTE: If no channels have beenprogrammed, channel 1 appears withdashesdisplayed.

The comm frequency knobs canbe used to select the desired channel(Figure 10).

FIGURE 10

Selecting desired channel

The unit will automatically exit thechannel mode, with the channelfrequency remaining in the STANDBYwindow, if no channel is selectedwithin 5 seconds after entering thechannel selection mode. The channelfrequency is then made the ACTIVEfrequency in the normal manner by

pressing the COMM TRANSFERbutton.

NOTE:An optional remote-mounted

channel switch may be installed thatincrements the next programmedchannel into the standby window eachtime the switch is activated. The unitis placed in the transmit mode bydepressing the MIC KEY button.

The unit has a stuck microphonealert feature. If the microphone iskeyed continuously for greater than

33 seconds, the transmitter stopstransmitting and the active Commfrequency flashes to alert the pilot ofthe stuck microphone condition.

NOTE: Radio control of airport runwaylighting is available at selectedairports to provide airborne control oflights by keying the aircraftsmicrophone. Approved lightingsystems may be activated by keyingthe microphone as indicated below:7 times in 5 sec. - Highest intensityavailable5 times in 5 sec. - Medium or lowerintensity3 times in 5 sec. - Lowest intensityavailable

Due to the close proximity ofairports using the same frequency, anairports radio controlled lightingreceiver may be set at a lowsensitivity, requiring the aircraft to berelatively close to activate the system.It is also important to be verydeliberate with the keying. Therequirement for the ground station

decoder is such that it will not respondto very rapid or staccatotransmissions. If the first attempt atlighting the runway lights isunsuccessful, repeat with a slower,

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more deliberate cadence ofmicrophone keying.

NAV Receiver

The right portion of the display isallocated to NAV receiver information.The frequency channeling is similar tothe COMM when operating in thefrequency mode (Figure 1A and 1B).The NAV increment/decrement knobsare located on the right hand side ofthe front panel. The outer knoboperates in 1 MHz steps and

increments/decrements theSTANDBY frequency display.The inner knob operates in 50

kHz steps. The NAV receivers lowerand upper frequency limits are 108.00MHz and 117.95 MHz. Exceeding theupper limit of frequency band willautomatically return to the lower limitand vice versa.

Depressing the NAV frequencytransfer button for 2 seconds or morewill cause the display to go in to the

ACTIVE ENTRY mode. Only theACTIVE frequency will be displayedand it can be directly changed byusing the NAV inc/dec knobs. Thedisplay will return to the

ACTIVE/STANDBY mode when theNAV frequency transfer button ispushed.

Depressing the mode button willcause the NAV display to go from the

ACTIVE/STANDBY format to theACTIVE/CDI (Course DeviationIndicator) format as shown in Figure11.

FIGURE 11

Nav display active VOR frequency/

CDI format

The vertical needle moves sideto side similar to a mechanical CDI.When the needle is centered, theaircraft is on the selected OBS

course. When the active frequency istuned to a VOR frequency, the centerof the CDI scale displays the TO orFROM indicator.

In the CDI mode, the increment/decrement knob (pushed in) channelsthe ACTIVE frequency window anddepressing the frequency transferbutton will cause the ACTIVE

frequency to be placed in blindstorage and the STANDBY frequency(in blind storage) to be displayed inthe ACTIVE window display.

When the ACTIVE window istuned to a VOR frequency, thestandby frequency area is replaced bya three digit OBS (Omni BearingSelector) display. The desired OBScourse can be selected by pulling outthe inner NAV frequency knob andturning it. The CDI needle may beautomatically centered with a TOindication by depressing the modebutton for 2 seconds. This OBSdisplay is independent of any OBScourse selected on an external CDI orHSI. An OBS in the middle of theNAV display will flash while the innerNAV frequency knob is pulled out.The CDI is displayed on the linebelow the frequency/OBS.

When the ACTIVE window istuned to a localizer frequency, thestandby frequency area is replaced byLOC (Figure 12).

FIGURE 12

Nav display Active localizer frequency/

CDI format

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When the received signal is tooweak to ensure accuracy the displaywill flag. See Figure 13.

FIGURE 13

VOR flag display

Depressing the mode button willcause the NAV display to go from the

ACTIVE/CDI format to the

ACTIVE/BEARING format. In theBEARING mode, the increment/decrement knob channels the

ACTIVE frequency window anddepressing the frequency transferbutton will cause the ACTIVEfrequency to be placed in blindstorage and the STANDBY frequency(in blind storage) to be displayed in

the ACTIVE window display. Inbearing mode of operation, the righthand window of NAV display showsthe bearing TO the station.

Figure 14 illustrates the NAV sideof the display in this mode.

FIGURE 14

VOR mode bearing to function

When a too weak or invalid VORsignal is received the display flags asshown in Figure 15.

FIGURE 15

VOR mode active/bearing,

flag display

Another push of the mode buttonwill cause the NAV display to go fromthe ACTIVE/BEARING format to the

ACTIVE/RADIAL format as shown in

Figure 16.

FIGURE 16

VOR mode

radial from function

In the RADIAL mode, theincrement/ decrement knob channelsthe ACTIVE frequency window anddepressing the frequency transferbutton will cause the ACTIVEfrequency to be placed in blindstorage and the STANDBY frequency(in blind storage) to be displayed inthe ACTIVE window display. In radial

mode of operation, the right handwindow of NAV display shows theradial FROM the station. Figure 16illustrates the NAV side of the displayin this mode.

When a too weak or invalid VORsignal is received the display flags asshown in Figure 17.

FIGURE 17

VOR mode

active/radial flag display

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Another push of the mode buttonwill cause the unit to go into theTIMER mode. See Figure 18.

FIGURE 18

Timer mode

When the unit is turned on theelapsed timer begins countingupwards from zero. The timer can be

stopped and reset to zero by pushingthe NAV frequency transfer button for2 seconds or more causing the ET onthe display to flash. In this state thetimer can be set as a countdown timeror the elapsed timer can be restarted.The countdown timer is set by usingthe NAV inc/dec knobs to set thedesired time and then pushing the

NAV frequency transfer button to startthe timer. The outer knob selectsminutes, the inner knob in the inposition selects ten second intervals,and the inner knob in the outposition selects individual seconds.

After the countdown timer reacheszero, the counter will begin to countupwards indefinitely while flashing for

the first 15 seconds. Or the elapsedtimer can also be reset to zero andstarted again after it has beenstopped and reset to zero by pushingthe NAV frequency transfer button.The Audio Alert, if installed, is thensounded.

The NAV ACTIVE and STANDBYfrequencies are stored in the memoryon power down and return on powerup.When the smallerincrement/decrement knob is pushedin, depressing the NAV TRANSFERbutton will interchange the ACTIVE

and STANDBY frequencies. The NAVIDENT knob is active in the pulled outposition so that both voice and identcan be heard. When this knob is

pushed in, the ident tone isattenuated. The volume of voice/identcan be adjusted by turning this knob.

Pilot Configuration

This mode can be accessed bypressing and holding the Nav ModeButton for more than 2 seconds andthen pressing the Nav Frequency

Transfer Button for an additional 2seconds, while continuing to hold theNav Mode Button. When the PilotConfig Mode is entered the unit willshow the SWRV mnemonic which isthe unit software revision level.

Adjustment pages can be accessedby MODE button presses.

The pilot may adjust twoparameters in the pilot configuration,the display minimum brightness andsidetone volume level.

Minimum Brightness (BRIM) willhave a range of 0 - 255. The dimmestis 0 and the brightest is 255.

Sidetone volume level is adjustedwhen SIDE is displayed. Values from0 - 255 may be selected with 0 beingleast volume, 255 being the greatest.

Subsequent presses of theMODE button sequences throughSWRV, BRIM, SIDE, and then back toSWRV.

Momentarily pressing the NavTransfer Button exits Pilotconfiguration mode. The Nav returnsto its pre-Pilot Config state with thenew brightness and sidetone levelsstored in non-volatile memory.

Default Mode

Turning on the KX 155A or KX165A while pressing either the COMM

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or NAV frequency transfer button willbring the unit up in the Direct TuneMode. 120.00MHz (120.000MHz in8.33 kHz KX 165A) will be the active

COMM frequency and 110.00 MHz

will be the active NAV frequency. Thiswill aid the pilot in blind tuning theradio in the unlikely event of displayfailure.

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KN 53

37

KN 53

Silver Crown TSOd Navigation Receiver

Operating the KN 53

Power Switch

This knob controls ON/OFF/VOL/IDENT. To turn on the unit, rotate theknob clockwise from the detentedOFF position. Rotation of this controlalso adjusts NAV audio volume. NAVvoice can be heard when the knob ispushed in. When the knob is pulledout, the Morse Code IDENT signalplus voice can be heard.

Frequency SelectionBy rotating the concentric

frequency selector knobs eitherclockwise or counterclockwise, thedesired operating frequency can bedialed into the standby displaywindow. A clockwise rotation willincrease the displayed frequencynumber, while a counterclockwise

rotation will decrease it. The largerselector knob is used to change theMHz portion of the frequency display;

the smaller knob changes the kHzportion in 50 kHz steps. At either bandedge of the 108.00 to 117.95 MHzfrequency spectrum, an off-scalerotation will wrap the display aroundto the other frequency band-edge(i.e., 117.95 advances to 108.95 withMHz knob rotation, or 117.00 with kHzknob rotation). DME and optionalinternal glideslope channeling arealso controlled by these selectorknobs.

NAV Frequency Operation

The desired operating frequencyis first entered into the standbydisplay. To activate, push the transferbutton. This will interchange thefrequencies in the use and standbydisplays and tune the receiver to thenew operating frequency.

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KN 62A/KN 64

39

KN 62A and KN 64

TSOd Silver Crown Digital DMEs

Operating the KN 62A and KN 64 DMEs

Operation

Turn on the unit only after enginestart-up. Also, turn avionics off prior toengine shut-down. These simpleprecautions should be practiced withall avionics. It will protect the solid-state circuitry from short duration highvoltage spikes and extend theoperational life of your avionics.

The 3-position function switchdetermines both the informationdisplayed and the channeling source.

Place the function switch on

Frequency (FREQ). The unit ischanneled internally with its own twoconcentric frequency selection knobs.The smaller of the two knobs has anin and an out position. When in thein position, this smaller knobchanges the 0.1 MHz digit (0.0, 0.1,0.2, etc.). When pulled out, it adds0.05 MHz to the frequency and tunes

in 0.1 MHz steps (0.05, 0.15, 0.25,etc.). Pushing the smaller knob insubtracts 0.05 MHz from thedisplayed frequency. The outer, largerknob changes the larger digits (1MHz, 10 MHz). In FREQ mode, the

unit will display distance and theselected frequency. (See Figure 19.)

FIGURE 19.

Distance/Frequency FREQ Mode.

Now move the function switch tothe Groundspeed/Time-to-Station(GS/T) position. The unit will hold theinternally selected frequency and will

display distance, groundspeed andtime-to-station. (See Figure 20.)

FIGURE 20.

Distance/Groundspeed/TTS GS/T Mode.

Rotating the frequency selectorwill have no effect on the display,because the DME is in FrequencyHold. This frequency hold feature inthe GS/T mode prevents accidental

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rechanneling of the DME when thefrequency is not displayed.

Place the function switch in theRemote* (RMT) position, and your

DME will be channeled when youselect your NAV frequency on theNAV receiver. Search time is usuallyabout one second. When the unitlocks on a ground station, it willdisplay distance, groundspeed andtime-to-station. (See Figure 21.)

FIGURE 21.

Distance/Groundspeed/TTS RMT Mode.

Prior to lock on, dashes will bedisplayed. (See Figure 22.)

FIGURE 22.

Prior to Lock On.

Note that you may have twofrequencies available at all times (oneremotely selected on the NAVreceiver and one internally selectedwith the units controls).

*Remote channeling requireswiring to the NAV receiver.

Operational Notes

The KN 62A and KN 64 have anaudio output for use in identifying theDME ground station being received.

The audio level is preset at thefactory, but may be easily adjustedthrough the top cover.

The unit electronically converts to

distance the elapsed time required forsignals to travel to and from theground station. This distance is thenindicated in nautical miles on theDistance/ Speed/Time-to-Stationdisplay. This distance, commonlyreferred to as slant range distance,should not be confused with actualalong-the-ground distance. The

difference between actual grounddistance and slant range is least atlow altitude and/or long range. If therange is three times the altitude orgreater, error is negligible.

The effective range of DMEdepends on many factors, mostimportant being the altitude of theaircraft. Other contributing factors arethe location and elevation of thestation, DME transmitter poweroutput, and receiver sensitivity.

The groundspeed featureincorporated in the unit measures therate of change in DME slant rangedistance with time. This speed is thenread from 0 to 999 knots in 1 knotincrements. To obtain accurategroundspeed, the aircraft must betracking directly to or from the station.To obtain accurate time to station, theaircraft must be tracking directly to thestation.

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KR 87

41

KR 87

Silver Crown ADF System

Operating the KR 87

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Turn-on

Rotate the ON/OFF/VOL knobclockwise from the detented OFFposition. The unit will be activated and

will be ready to operate. Rotation ofthis control also adjusts audio volume.The KR 87 has audio muting whichcauses the audio output to be mutedunless the receiver is locked on avalid station.

Frequency Selection

The active frequency (to which

the ADF is tuned) is displayed in theleft side of the window at all times. Astandby frequency is displayed in theright side when FRQ is annunciated.The standby frequency is placed inblind memory when either FLT(Flight Time) or ET (Elapsed Time)mode is selected.

With FRQ annunciated, the

standby frequency is selected usingthe frequency select knobs which maybe rotated either clockwise orcounterclockwise. Pull the small innerknob out to tune 1s. Push the smallerinner knob in to tune 10s. The outerknob tunes the 100s and the 1000sup to 1799.

The standby frequency selected

may then be put into the activewindow by pressing the FRQ button.The standby and active frequencieswill be exchanged (flip-flopped), thenew frequency will become active,and the former active frequency willgo into standby.

Operating Modes

Antenna (ANT) mode is selectedand annunciated when the ADF

button is in the out position. ANTprovides improved audio receptionfrom the station tuned and is usuallyused for identification. The bearing

pointer in the KI 227 indicator will bedeactivated and immediately turn tothe 90 relative position and remainthere during ANT reception.

The ADF mode is selected andannunciated when the ADF button isin the depressed position. ADFactivates the bearing pointer in the KI227 indicator, causing it to movewithout hesitation to point in thedirection of the station relative to theaircraft heading. The compass cardon the KI 227 may be rotated asdesired by using the heading knob.

NOTE: The KI 227-01 or KI 228-01indicators, when installed with aBendix/King KCS 55A CompassSystem, have a slaved compass card.Magnetic heading of the aircraft willbe under the lubber line. Theindication of this compass card

should be compared with that of

the KI 525A master indicator fromtime to time. Check especially after

steep bank turns and taxi turns. If a

discrepancy between the two

readings exists, the KI 227-01 or KI

228-01 compass card should be

synchronized to the KI 525A

compass card by rotating the

SYNC knob on the indicator.

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KR 87

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Outside of the United Statessome stations are unmodulated anduse an interrupted carrier foridentification purposes. The BFO

mode, activated and annunciatedwhen the BFO button is depressed,permits the carrier wave and theassociated Morse code identifierbroadcast on the carrier wave to beheard.

ADF Test

(PRE-FLIGHT OR IN-FLIGHT)

Select ANT mode. This will cause thebearing pointer to move directly to theparked 90 position. Make sure theunit is tuned to a usable frequency.Now select ADF mode and the needleshould move without hesitation to thestation bearing. Excessivesluggishness, wavering or reversalsindicate a signal that is too weak or a

system malfunction.

Operating the Timers

The flight timer will always beautomatically reset to :00 wheneverpower is interrupted either by theavionics master switch or the unitsON/OFF switch. An optional externalswitch may be installed which, when

activated, will stop or start the flighttimer. This switch would be of useduring a nonrefueling stop whenresetting the flight timer is not desired.On some aircraft it may be desirableto use the aircraft strut switch insteadof a manual switch to stop and startthe flight timer. It should beemphasized that the start/stop

function will only operate with powerapplied to the unit. Always read flighttime prior to power shutdown.

Flight time or elapsed time aredisplayed and annunciatedalternatively by depressing theFLT/ET button. The flight timercontinues to count up until the unit isturned off or stopped with an externalswitch. The elapsed timer may bereset back to :00 by pressing theSET/RST button. It will then startcounting up again.

NOTE:Pressing the SET/RST buttonwill reset the elapsed timer whether itis being displayed or not.)

The elapsed timer also has acount-down mode

To enter the countdown mode,the SET/RST button is depressed forabout two seconds, or until the ETannunciation begins to flash. It is nowin the ET set mode, and a time up to59 minutes, 59 seconds may bepreset into the elapsed timer with the

concentric knobs. The preset time willbe displayed and remain unchangeduntil SET/RST is pressed again,which will start the elapsed timercounting down from the preset time.When the timer reaches :00 it will startto count up as the display flashes for15 seconds and an aural alarm, ifinstalled, is activated for about 1second.

NOTE: The standby frequency whichis in memory while flight time orelapsed time modes are beingdisplayed may be called back by

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pressing the FRQ button, thentransferred to active use by pressingthe FRQ button again.

While FLT or ET is displayed thein use frequency on the left side ofthe window may be changed, by usingthe frequency select knobs, withoutany effect on the stored standbyfrequency or the other modes. Thisfeature is especially useful whensearching for stations with unknownfrequencies.

Erroneous ADF BearingsDue to Radio Frequency

Phenomena

Station Overlap

In the U.S., the FCC, whichassigns AM radio frequencies,occasionally will assign the samefrequency to more than one station in

an area. Certain conditions, such asNight Effect, may cause signals fromsuch stations to overlap. This shouldbe taken into consideration whenusing AM broadcast stations fornavigation.

Sunspots and atmosphericphenomena may occasionally distortreception so that signals from two

stations on the same frequency willoverlap. For this reason it is alwayswise to make positive identification ofthe station being tuned, by switching

the function selector to ANT andlistening for station call letters.

Electrical Storms

In the vicinity of electrical storms,

an ADF Indicator pointer tends toswing from the station tuned towardthe electrical discharges. Location ofthe storm can be useful information,but the erratic behavior of the pointershould be taken into account.

Night Effect

This is a disturbance particularly

strong just after sunset and just afterdawn. An ADF indicator pointer mayswing erratically at these times. Ifpossible, tune to the most powerfulstation at the lowest frequency. If thisis not possible, take the average ofpointer oscillations to determinerelative station bearing.

Mountain Effect

Radio waves reflecting from thesurface of mountains may cause thepointer to fluctuate or show anerroneous bearing. This should betaken into account when takingbearings over mountainous terrain.

Coastal Refraction

Radio waves may be refracted

when passing from land to sea orwhen moving parallel to the coastline.This should be taken into accountwhen operating near coastal areas.

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KT 76C

45

KT 76C

Bendix/King Panel-Mounted Transponder

KT 76C OPERATION

About Transponders

Your Honeywell Bendix/King

transponder is a radio transmitter andreceiver which operates on radarfrequencies. Receiving ground radarinterrogations at 1030 MHz, it returnsa coded response of pulses togroundbased radar on a frequency of1090 MHz.

As with other Mode A/Mode Ctransponders, the KT 76C replies with

any one of 4,096 codes, which differin the position and number of pulsestransmitted. By replying to groundtransmissions, your KT 76C enables

ATC computers to display aircraftidentification, altitude and groundspeed on Enroute, Approach orDeparture Control radar screens.When the IDENT button is pressed,

your aircraft will be positivelyidentified to the Air Traffic Controller.

Operating the KT 76C

Before starting your aircraftsengine, make sure that the KT 76C

function selector knob, or youravionics master, is turned to OFF.

After engine start, turn the functionselector knob to SBY (standby). Giveyour transponder about 45 seconds tobecome operational.

Select the proper reply code bypressing the desired code entrybuttons. The reply code will bedisplayed in the code window. Beforetakeoff, rotate the function selectorknob to the ALT (altitude) position for

Mode C altitude reporting to ATC. Ifyou do not have an encodingaltimeter, rotate the function switch toON for Mode A reporting.

Altitude Display

The KT 76C displays Flight LevelAltitude, marked by the letters FLand a number in hundreds of feet, on

the left side of the display. Forexample, the reading FL 065corresponds to the altitude of 6,500feet, referenced to 29.92 inches ofmercury (or 1013 hP) at sea level.Flight Level Altitude represents

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pressure altitude, and should not beconfused with true altitude. Pleasenote that the displayed altitude maynot agree exactly with the aircrafts

altimeter when flying below 18,000feet, because encoders are preset to29.92 inches of mercury. Anencoders altitude transmission isautomatically corrected for properaltimeter setting by a ground basedcomputer, to present the correctaltitude to the controller.

Ranging from -1,000 to +99,000

feet, Flight Level Altitude is displayedonly when altitude reporting isenabled. If the altitude window isblank or shows a series of dashes (asin the case of an invalid altimetercode being reported), altitudereporting will be disabled.

CLR Button

Code entry mistakes arecorrected, one digit at a time, bypressing the CLR button andreentering the correct code. The lastactive code will be displayed if acomplete four-digit code has not beenentered and there is no activity on anyof the code entry buttons, the VFRbutton, or the CLR button for fourseconds.

VFR Button

Momentarily pressing the VFRbutton will enter a pre-programmedVFR code, typically 1200, in the codewindow. Pressing and holding theVFR button for two seconds will causethe last active code to be displayed.

During installation, it may bedesired to set the default VFR code toa code other than 1200. The VFRcode is programmed by the following

sequence:

1. Place the unit in standby.2. Enter the desired VFR code with

the ident code pushbuttonswitches.

3. Depress the VFR pushbuttonwhile holding the IDTpushbutton in its depressed

position.

Reply Indicator

The reply indicator blinks toindicate that the KT 76C is functioningproperly and replying tointerrogations.

Squawk Ident

When you are asked to ident byATC, press the IDT button. Th

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