Bendix/King KMA 24 - User Manual

KMA 24 and KMA 24H
Bendix/King
Audio Control Systems
KMA 24 and KMA 24H Bendix/King Audio Control Systems
Honeywell
23500 W. 105th Street, Olathe, KS 66061-1950
Telephone 913.712.2613 Fax 913.712.5697
Toll-Free in U.S. 877.712.2386
www.bendixking.com
Honeywell 23500 W. 105th Street, Olathe, KS 66061-1950 Telephone 913.712.2613 Fax 913.712.5697 Toll-Free in U.S. 877.712.2386 www.bendixking.com
© 2000 Honeywell
2/00 006-08316-0008 5K Printed in U.S.A.
Policy Notice: In keeping with Honeywell’s goal of constant
product improvement, product specifications and design
features may be altered without notice.
Avionics installation requires special skills, tools and equipment.
Our limited warranty is valid only for equipment installed in
accordance with our sales policy.
Optional Intercom Modes
The optional installation of a remote,
three-position switch for intercom operations with the KMA 24H provides three modes: Isolate, Normal (NORM) and Private. In Isolate, the pilot takes himself out of the intercom loop while the other four intercom positions remain active. In Normal, all five intercom positions are tied together. In Private, the pilot and copilot positions are linked together for two-station hot mike operation. At the same time, the other three intercom positions have independent three-station intercom operation. Receiver Selection
The top row of push buttons on the
console controls the audio selection for the speaker, and the bottom row selects audio for headphones. The selections are independent, and any audio input can be selected for speaker or headphones or both. These push buttons allow audio selection independent of the AUTO feature described earlier.
The KMA 24 and KMA 24H can control
as many as six receivers. Both units also have two unswitched inputs for uses such as the radar altimeter audio alert or the ring signal from a radiotelephone.
To listen to a specific receiver, simply
press the corresponding headphone or speaker
button “in.” To disconnect that receiver, press the button again. It will return to the “out” position.
For both the KMA 24 and KMA 24H,
volume of audio input from transceivers and receivers is set with the volume controls of each individual radio. Transmitter Selection
The rotary switch on the right side of
the KMA 24 and KMA 24H consoles selects the desired transmitter for the cockpit micro- phones. In the KMA 24, the off position shuts off power to the speaker amplifier and marker beacon receiver. (The headphone amplifier operates whenever the aircraft electric power is on.)
With the KMA 24, the next position
of the rotary switch may be either “TEL” (radiotelephone) or “HF” (high frequency transceiver.) The former is more likely to be found in aircraft used mostly for domestic operations, the latter for international operations.
The COMM 1 and 2 positions (COMM
1-4 or 1-5 for KMA 24H) are for transmitting on the frequencies set up on those respective communication transceivers.
The “INT”, “PA” and “EXT”, and “EMG”
positions are discussed above.
Other Combinations Of Features KMA 24 KMA24H KMA 24 with TEL and ADF 1 and 2 KMA 24H with 4 COMMs and 2 ADFs KMA 24 with HF and AUTO KMA 24H with 5 COMMs and 1 ADF KMA 24 with HF and ADF 1 and 2
Specifications
TSO Compliance:
Marker Beacon Receiver: TSO C35d,
Class A
KMA24—Env. Cat. A1D1/A/PKS/
XXXXXXZBAAA
Audio Amplifier: TSO C50b
KMA 24H—Env. Cat. A2D1/A/KPS/
XXXXXXB/AB/BZ/A
Weight: 1.7 lb. (0.77kg)
Physical Dimensions:
Length behind panel: 6.8 in. (17.30 cm)
Width: 6.25 in. (15.88 cm)
Height: 1.3 in. (3.30 cm)
Duty Cycle: Continuous
Power Requirements (not including
instruments lights):
KMA 24 13.75v 27.5v
Idle current, mike
switch on 110 ma 170 ma
Idle current, mike Less than Less than
switch off 8 ma 16 ma
Max. operating
current 1.9 a 1.9 a
KMA 24H
Idle current 350 ma 500 ma
Max. operating
current 1.8 a 1.8 a
Temperature Range: -20ºC to +55º with
brief operation at +70ºC (KMA 24),
-20ºC to +70ºC continuous (KMA 24H)
Marker Beacon Receiver
(KMA 24 only)
Frequency: Crystal-controlled at 75 MHz
Sensitivity: LO 1,000µv Hard
HI 200µv Hard
Selectivity: 6 db at ± 10 kHz Min.
40 db at ± 200 kHz Max.
Input Impedance: 50 ohms
Output: Capable of 4 mw into isolation
amplifier impedance of 500 ohms.
Isolation Amplifiers:
KMA 24 Inputs: KMA 24 models without
AUTO accommodate three transceivers
and six external receivers. Models with the
AUTO function accommodate three trans-
ceivers and five external receivers. All
models also have two unswitched inputs.
(Typical use: radar altimeter aural warning
and radiotelephone ringer.)
KMA 24H Inputs: KMA 24H models
accommodate five transceivers and five
external receivers or four transceivers and
six receivers. All models also have two
unswitched inputs. (Typical use: radar
altimeter aural warning and radiotele-
phone ringer.)
KMA 24 Input Impedance: 500 ohms
KMA 24H Input Impedance: 320 ohms
for all ICS inputs, 500 ohms for all
audio inputs
Input Isolation:
KMA 24: 40 db between inputs
KMA 24H: 60 db between inputs
Input Muting (when mike is keyed):
At least 55 db
Speaker Output:
With 13.75v Supply:
Into 4 ohm load: 7 w (KMA 24)
6 w (KMA 24H)
Into 8 ohm load: 4 w
Into 8 ohm load from
8 ohm tap: 6 w (KMA 24H)
With 27.5v Supply:
Into 4 ohm load: 12 w (KMA 24)
10 w (KMA 24H)
Into 8 ohm load: 6.5 w
Into 8 ohm load
from 8 ohm tap: 10 w (KMA 24H)
Headphone Output:
KMA 24: 50 mw into 500 ohm load
KMA 24H:
With 27.5v supply: 120 mw into each
500 ohm load
With 13.75v supply: 20 mw into each
500 ohm load
Output Characteristics:
Distortion: Less than 5 percent at rated
output
Frequency response:
KMA 24: Within 6 db from 350 hz to
6,000 hz
KMA 24H: Within 3 db from 350 hz to
6,000 hz

Summary

Compact TSOd Audio Control Systems Overview

KMA 24 Audio Control System Features

Details KMA 24 controls, including speaker/headphone selection and microphone routing options.

KMA 24 H Audio Control System Features

Details KMA 24H controls, featuring intercom and advanced routing capabilities for multiple radios.

Built-In Marker Beacon Receiver (KMA 24)

Describes the KMA 24's marker beacon receiver with a three-light display for visual and aural indication.

Five-Station Intercom System (KMA 24 H)

Covers the KMA 24H's intercom with hot mike, VOX, and keyed activation modes for crew communication.

Operating the KMA 24 and KMA 24 H Systems

Auto Receiver Audio Select Operation

Explains the "AUTO" feature for automatic matching of receiver audio with selected transmitters.

KMA 24 Marker Beacon Receiver Operation

Details marker beacon sensitivity, testing, lamp dimming, and audio identification.

KMA 24 H Intercom System Operation

Explains KMA 24H intercom modes, sensitivity, volume, and priority settings for crew communication.

Receiver and Transmitter Selection

Receiver Selection Controls

Details using push buttons for speaker/headphone selection, independent of other functions.

Transmitter Selection Rotary Switch

Describes the rotary switch for selecting COMM, TEL, HF, INT, PA, and EXT transmission modes.

Optional Intercom Modes

Covers Isolate, Normal, and Private modes for optional three-position remote intercom switches.

KMA 24 and KMA 24 H Specifications

TSO Compliance and System Categories

Lists the TSO compliance standards and environmental categories for the KMA 24 and KMA 24H.

Physical Dimensions and Weight

Provides the physical size, depth, and weight details for the KMA 24 and KMA 24H units.

Power Requirements and Temperature Range

Details electrical power consumption and operating temperature limits for both models.

Marker Beacon Receiver Specifications (KMA 24)

Lists frequency, sensitivity, and selectivity specs for the KMA 24's built-in marker beacon.

Audio Output and Input Specifications

Covers input impedance, output power, isolation, distortion, and frequency response.

Bendix/King KMA 24 Specifications

KMA 24

Power

voltage	13.75v, 27.5v
idle current, mike switch on	110 ma
idle current, mike switch off	Less than 8 ma
max. operating current	1.9 a

Operating Environment

temperature range	-20ºC to +55ºC with brief operation at +70ºC
frequency	75 MHz
sensitivity LO	1, 000µv Hard
sensitivity HI	200µv Hard
selectivity	6 db at ± 10 kHz Min. 40 db at ± 200 kHz Max.

Audio and Output

input impedance	500 ohms
speaker output with 13.75v supply into 4 ohm load	7 w
speaker output with 27.5v supply into 4 ohm load	12 w
headphone output	50 mw into 500 ohm load
distortion	Less than 5 percent at rated output
frequency response	Within 6 db from 350 hz to 6, 000 hz

Weight and Dimensions

weight	1.7 lb. (0.77kg)
length	6.8 in. (17.30 cm)
width	6.25 in. (15.88 cm)
height	1.3 in. (3.30 cm)

KMA 24H

Power

voltage	13.75v, 27.5v
idle current	350 ma
max. operating current	1.8 a

Operating Environment

temperature range	-20ºC to +70ºC continuous
input impedance	320 ohms for all ICS inputs, 500 ohms for all audio inputs
input isolation	60 db between inputs
speaker output with 13.75v supply into 4 ohm load	6 w
speaker output with 27.5v supply into 4 ohm load	10 w

Audio and Output

headphone output with 27.5v supply	120 mw into each 500 ohm load
headphone output with 13.75v supply	20 mw into each 500 ohm load
distortion	Less than 5 percent at rated output
frequency response	Within 3 db from 350 hz to 6, 000 hz

Weight and Dimensions

weight	1.7 lb. (0.77kg)
length	6.8 in. (17.30 cm)
width	6.25 in. (15.88 cm)
height	1.3 in. (3.30 cm)