section 7-avionics Flashcards
where can 2 electric fans be fitted to cool the avionics equipment?
LH and RH avionics racks
when do the avionics cooling fans operate?
whenever the 28V DC BUS 1 is enegerised
what protects the avionics cooling fans?
AVIONIC COOL/BUS 1 on the AC/DC breaker panel
can the avionics be operated individually if the avionic master circuit fails?
yes
what does the intercom system provide?
communication between pilots, and monitoring of all COM and radio NAV equipment installed in the airplane
what does the intercom system consist of?
2 microphone buttons, headset connections and 2 ICS EMERG switches on the pedestal panel
what powers the intercom?
28v DC
what protects the intercom system?
- ICS 1/ESS BUS on the overhead breaker panel
- ICS 2/BUS 2 on the AC/DC breaker panel
what is the intercom operating temperature range?
-20-+55C
how do we transmit?
set the transmitter selector knob to the desired position and depress the. button on the control wheel
what mode is HOT MIKE not available?
intercom
how is communication receiver audio selected?
by depressing the appropriate communication selector button
can more than 1 comms receiver be selected for receiver audio?
yes
how are navigation recievers selected?
by depressing the appropriate navigation audio selector button
what if the VOICE button is pressed?
identification signals (morse code) are suppressed and the voice transmission is clear- when the button is released voice and identification signals are of equal strength
what is fed to the inter phone system when a warning light illuminates?
1kHz signal is fed to the inter phone
what must be pressed to allow the pilots to transmit without using the headsets?
SPKR
what does the ICS emergency switch do?
bypasses the normal ICS amplifier of the ICS control unit in case of amplifier malfunction by connecting the microphone directly to the selected communication system
what is the headphone connected to in the EMERG position?
the speaker amplifier instead of the phone amplifier
what must we do on the ICS panel if the ICS emergency switch is set to EMERG?
the SPKR button must be pushed in
what is not possible with the ICS emergency switch set to EMERG?
intercommunication between pilot and co-pilot
what will operation of the CALL button on either control wheel do?
trigger an audio signal to call the attention of the passengers with a 2 tone chime
what do we hear when the NO SMOKE and/or fasten seatbelt signs are either ON or OFF?
2 tone chime
what happens to signal and voice communication volume with either speed lever out of the LOW position?
volume will increase automatically
how are pax announcements made?
switching the transmitter selector knob to PA and depressing the MIC button
what does the ground clearance switch allow?
enables the pilot to await clearance from ATC with all equipment off except VHF COM 1 provided the avionics master switch is off
what are the 3 modes of the VHF communication system?
frequency, channel and direct tuning
how many preset frequencies can be recalled into the STBY display in channel mode?
9
what is direct tuning mode used for?
a backup allowing frequency changes to be made directly into the USE display
what does the VHF communication system consist of?
- pedestal mounted receiver/transmitter
- 1 VHF communication antenna for each system
- interconnecting cables
what protects the VHF communication system?
- VHF 1/ESS-BUS on the overhead breaker panel
- VHF 2/BUS 2 on the AC/DC breaker panel
what is the VHF transmitter power?
up to 16 watts
what is the operating temperature range of the VHF communication system?
-20-+55C
how do we activate the VHF communication system?
rotate the on/off/volume knob clockwise from the detented off position
why should we switch on VHF comms after engine start?
to protect solid-state circuitry
how to we use manual squelch?
pulling the volume control knob
how do we know we are transmitting using VHF 1?
T indication
how do we check the VHF system is in the desired mode?
pulling small frequency selector knob out
what if a channel number is displayed in the USE display?
the VHF system is in channel mode
what if a frequency is displayed in the USE display?
the VHF system in frequency mode
how do we change the VHF mode of operation?
- press the frequency transfer button for approximately 3 seconds until a flashing channel number is displayed in the USE display
- pull out the small frequency selector knob and rotate it until a flashing zero is displayed in the USE display. the STBY display shows — or uuu
- to select frequency mode, select — in the STBY display and press the frequency transfer button. a frequency is displayed in both displays
- to select the channel mode, select uuu in the STBY display and press the frequency transfer button. a frequency is displayed in both displays
- to select the program mode in order to change the frequency of a preset channel, select uuu in the standby display
what is the HF system capable of?
receiving and transmitting on any 0.1khz between 2000 and 26,999.9khz
how many frequencies can be preset for fast selection during flight on the HF communication system?
99
what does the KHF 950 HF system utilise?
an LSI (large scale integration) microprocessor and a frequency synthesiser.
what does the HF system transmit with?
100 watt of peak envelope power in single sideband.
what is the average power of the HF on AM?
25 watt
what are the HF systems 2 possible modes?
upper and lower sideband (A3J) and AM (A3H)
what does the HF system consist of?
- 2 KCU 951 panel-mounted control units
- 2 KAC 952 remote power amplifier and antenna couplers
- 2 KTR 953 remote recivers/exciters
- 2 bridging amplifiers
- 1 dual antenna adapter
- 1 HF 1/2 selector switch
- 1 antenna
what protects the HF communication system?
HF1/BUS 1 on the AC/DC breaker panel
HF2/NON ESS BUS on the LH avionic rack breaker panel
what is the operating temp range of the HF system?
- remote units -55C to 70C
- control/display -20C to 70C
what does the HF 1/2 selector switch do?
selects the active HF system
what is the HF system connected to and partly controlled by?
intercom system
how long does the HF system take to warm up?
2 minutes
what are the 2 methods of frequency selection on the HF system?
direct tuning and channelised operation
what does the FREQ/CHAN button on the HF system do?
selects either direct tuning or preset channel operation
in= CHAN (then select desired preset channel)
out= FREQ (becomes operational on the frequency last transmitted on)
what should be done to protect the HF solid state circuitry?
system should only be activated after engine start up and the VOL control knob on the ICS unit set to a middle position
how do we set SQUELCH on the HF system?
rotating the SQUELCH knob clockwise until background noise is heard and then counterclockwise until barely edible or absent
what does the CLARIFIER knob on the HF system do?
assists in single sideband SSB reception when the ground station is slightly off frequency resulting in unnatural voice quality
how do we operate the CLARIFIER knob on the HF system?
when receiving an unclear transmission, pull out the knob and rotate it either way to give natural voice quality
what is the MODE button on the HF system used for?
USB,LSB and AM and is set by momentarily pressing the button until the desired mode is annunciated
how do we tune the HF antenna once we have selected the desired receiving frequency or channel?
press the MIC button
how long will tuning of the hf antenna take?
about 3 seconds
how do we know tuning of the HF antenna Is complete?
the TX stops flashing and the frequency digits reappear
how do we select desired transmission mode when the FREQ/CHAN button is out on the HF system?
push MODE until the desired transmission mode is displayed in the lower part of the display window
what is the PGM button on the HF system used for?
used to change the frequency and emission mode of a preset channel
what must be the same for transmitting and receiving on HF?
operating mode
what are the 2 ways to set up an HF channel?
recieve only and simplex
what will indicate a fault on the HF system?
flashing digits- this warning can be cleared by pressing the mic button
what is the range of VOR/LOC frequencies that the NAV receiver can use?
108-117.95mhz with 50khz spacing
what frequency range does the automatically tuned glideslope reciever use?
329.15-335mhz with 150khz spacing
how many VHF NAV systems are provided?
2
what powers the NAV system?
28v DC
what protects the NAV system?
NAV 1/ESS BUS on the overhead breaker panel
NAV 2/BUS 2 on the AC/DC breaker panel
how do we silence the morse code on the NAV receiver?
push the knob in (voice info will still be heard)