Honeywell KHF 1050, System Installation Manual

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KHF 1050 SYSTEM INSTALLATION MANUAL
Page 2036
Revison 2
23-10-09
Apr/2006
5.E. Analog Inputs and Outputs
5.E.(1) Microphone Input
The microphone input will operate with voice signal levels typically from 0.20
VRMS to 2.5 VRMS. A DC bias current equivalent to that provided by a voltage
source of +15 VDC in series with 470 ohms is provided on pin 21. The
audio-frequency input impedance is 150 ohms (typical).
5.E.(2) Receiver Audio/Sidetone Audio Output from the Receiver/Exciter
(J10531-40 and 82)
The Receiver Audio/Sidetone is a balanced audio output capable of supplying
100 mW into a 600 ohm load. This signal is the combination of the receiver
audio output signal and the transmitter sidetone signal. Also included in this
audio is the antenna coupler tune tone, if activated. When operating in data
modes, this output is muted.
This output is factory adjusted to 7.75 VRMS +/-5% (100 mW) into 600 ohms,
at maximum volume. As shipped from the factory, the level of the sidetone is
the same as the level of the receiver audio.
The Receiver Audio/Sidetone output level can be adjusted three ways. It can
be adjusted via the volume control on the ARINC 429 controller, if the controller
is equipped with volume control capability, as is the PS440. It can also be
adjusted by use of a service adjustment located on the top of the Receiver
Exciter. Refer to Paragraph
“10.B. Field Alignment” for the location of this
adjustment. Accessing this adjustment requires removing the dust cover.
Finally, the transmitter sidetone level can be adjusted with respect to the
receiver audio by use of the KHF 1050 Maintenance Program software (PN
222-30144-0000). Changing the sidetone level also changes the level of the
antenna coupler tune tone, if activated. Refer to Paragraph
“10.C.(6)
Installation Setup” .
5.E.(3) SELCAL AUDIO Output from Receiver/Exciter
(J10531-19 & 61)
This SELCAL Audio Output provides an unsquelched AM-mode balanced
audio output compatible with an ARINC 714 SELCAL decoder. Regardless of
the operating mode selected by the pilot, this output is always an AM
demodulated signal. The signal level is factory adjusted to 1 mW (.775 Vrms)
into a 600 ohm load, and can be adjusted by a service adjustment located on
the top of the Receiver Exciter. See Paragraph
“10.B. Field Alignment” for the
location of this adjustment. Accessing this adjustment requires removing the
dust cover.