MGL Avionics Vega ASV-1 User manual

Introduction
The ASV-1 is a 2 1/4” (57mm) sunlight readable encoding altimeter airspeed and wide range vertical speed indicator.
The altimeter contains an internal high accuracy 24 bit digital altitude sensor which calculates altitude from -1500 ft up to
a maximum of +35000 ft. The ASV-1 outputs various formatted RS232 serial data protocols compatible with serial input
transponders such as that from Garmin Magellan Northstar Trimble Microair etc. The altimeter can display altitude in
feet or meters and local pressure can be set in millibars or inches of mercury
The VSI indicator can be displayed in either feet/minute (ft/min) or meters/second (m/s). The VSI can be calibrated by the
user once the instrument has been installed in the aircraft.
Airspeed is based on the pressure generated by a pitot tube system and a static port is provided as well for use by high
speed aircraft. The ASV-1 can measure airspeed from 20mph to 250mph (Version 1) 20mph to 350mph (Version 2) and
20mph to 320mph for the ASV-1HS (High Speed version). All are well suited to slower aircraft due to very good sensitivity
and linearity at low air speeds. Airspeed can be indicated in statute miles per hour (mph) kilometers per hour (km/h) or
nautical miles per hour (kts). The ASV-1 also provides a programmable Vs and Vne airspeed alarm output. ASI sensitivity
can be calibrated by the user to cater for errors caused by pitot tube placement.
In addition the ASV-1 provides an encoder test function flight timer since takeoff and records the maximum airspeed
reached. The ASV-1 provides a parallel Gillham code interface when used in conjunction with the MGL Avionics CNV-ALT.
Please note that the ASV-1 Version 2 replaces both the ASV-1 Version 1 and the ASV-1HS (High speed) unit.
Vega ASV-1
Altimeter, Airspeed (ASI) and Vertical
Speed Indicator (VSI)
perating Manual – English 1.13

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1 Features
•Large 1.8” high resolution 160x128, sunlight readable, wide viewing angle, 1000 cd/m2 T T LCD display
• A choice of 3 different display screens with either an Altitude, VSI or Airspeed tape
• An internal high accuracy 24 bit digital altitude sensor calculates altitude from –1500 ft up to a maximum
of 35000 ft (-457m to 10668m)
• The ASV-1 outputs various formatted RS232 serial data protocols compatible with serial input transpon-
ders such as that from Garmin, Magellan, Northstar, Trimble, Microair etc.
• Provides a parallel Gillham code interface for transponders when used in combination with the MGL
Avionics CNV-ALT
• Built in encoder test function
• The altimeter can display altitude in feet or meters
• Local pressure can be set in millibars or inches of mercury
• Contains a wide range VSI indicator from +/-20 ft/min to as high as +/-10000 ft/min
• VSI units can be in feet/minute (ft/min) or in meters/second (m/s)
• The ASV-1 measures airspeed from 20mph to 250mph (Version 1)
• The ASV-1 measures airspeed from 20mph to 350mph (Version 2)
• The ASV-1HS (High Speed version) measures airspeed from 20mph to 320mph
• Both units are well suited to slow aircraft due to very good sensitivity and linearity at low air speeds
• Includes a flight timer since takeoff
• Airspeed units can be set to miles per hour (mph), kilometer per hour (km/h) or nautical miles per hour
(kts)
• Contains a programmable Vs and Vne airspeed alarm output
• Provides a 50 entry flight log that stores duration of each of the last 50 flights. The flight timer can either
be started automatically or by using a front push button
• Records maximum airspeed reached in permanent memory
• Includes a RS232 serial output for interfacing to external equipment e.g dataloggers, CNV-ALT etc.
• Standard 2 1/4” (57mm) aircraft enclosure (can be front or rear mounted)
• Rotary control plus 2 independent buttons for easy menu navigation and user input
• Wide input supply voltage range of 8 to 30V DC
• 1 year limited warranty

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2 Layout
3 Main Display
The ASV-1 has 3 different display screens. The main display screen can be selected by using the “TAPE” menu option.
3.1 VSI "TAPE" Display
F2 / Down Button:
Menu system: Softkey button
Normal display: Press to view the
Timers and Max Values display
Sunlight readable color
graphic display:
Backlight can be adjusted in the
menu system
Rotary Control (Up/Down) & Enter Button:
Press the rotary control during the normal display screens to access the menu system. Rotate anti/clockwise
for up/down menu scrolling. Rotate the rotary control during the normal display mode to adjust the local
pressure. Local pressure can be set in either mB or in “Hg.
F1 / Up Button:
Menu system: Softkey button
Normal Display: Start / Stop the
flight timer (Manual flight only)
2 1/4” (57mm) enclosure.
Can be front or rear mounted
VSI scale indication
VS I (Vertical Speed Indication)
VSI unit
Altitude value
Local pressure readout (Either in mB or in “HG)
VSI value
Altitude unit
Airspeed unit
Airspeed value

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3.2 Altitude "TAPE" Display
3.3 Airspeed "TAPE" Display
VSI unit
Altitude Tape
Altitude Value
Altitude Bug
Local pressure readout (Either in mB or in “HG)
Altitude unit
Airspeed value
Airspeed unit
VSI value
Airspeed unit
Airspeed tape
Vs0 (Min safe speed landing)
Vs1 (Min safe speed normal)
Vfe (Max flap speed)
Vno (Max maneuvering speed)
Vne (Max exceed speed)
Altitude unit
Altitude Value
Airspeed value
VSI unit
VSI value
Local pressure readout
(Either in mB or in “HG)

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3.4 Start / Stop flight display
Press the F1/Up button during the normal display mode
to manually start/stop a flight. This key is only active if
the ASV-1 is setup to select the manual flight option
under the “TIMERS” setup menu.
3.5 Altitude Bug
Press the F1/Down button during the altitude “TAPE” display to access the altitude bug setting screen. Press the F1/UP
key to set the altitude bug to the current altitude or use the rotary control to adjust the altitude bug. Press the F2/Down
key to change the increment / decrement unit to 50 or 500. Press the rotary control to exit and save.
The bug will be yellow when in the display screen and cyan when either above or below the limits of the display.
3.6 Timers display
This display can be accessed by pressing the F2/Down button during the normal
display mode.
3.7 Maximum Airspeed display
This display can be accessed by pressing the F2/Down button during the normal display
mode. Press the F1/Up button when the max values display is showing to reset the
maximum values to the current airspeed.
Note: The maximum airspeed is stored in non-volatile
memory and is recalled on power-up.

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4 Menu System
Press the rotary control button during the normal display mode to enter the menu system. Use the rotary control to navi-
gate through the menu system.
4.1 Exiting the menu system
Press the F1/Up button to exit the menu system when the “EXIT” soft key is shown. All changes made during navigation
of the menu system will be saved in non-volatile memory upon exiting. The instrument will not save any changes if you re-
move power before exiting the menu system.

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4.2 Flight Timer
View Flight Log:
Use the rotary control to view the next flight log entry.
Erase Flight Log:
Use this function to erase the flight log stored in the ASV-1.
Flight:
Select whether you want the ASV-1 to automatically detect a flight or whether the pilot must press the F1/Up button to
start/stop a flight. We recommend you select automatic flight detection.
T/O Airspeed:
This menu option is only shown if the “DETECT” flight mode is selected. Enter the takeoff airspeed threshold that you
want the flight timer to start incrementing.

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4.3 ALT Setup (Altitude Setup)
Altitude Unit:
Select if you want the altitude displayed in ft (feet) or m (meters).
Pressure Unit:
Select if you want the local pressure displayed in mb (millibars) or “Hg (inches of mercury).
Resolution:
Select the resolution of the altitude value a selection of 1 10 25 or 100 ft or m can be selected.
Position:
Select whether you want the altitude display on the top or on the bottom of the main display (VSI Tape display only).
ALT Calibrate
This section allows for the calibration and fine tweaking of the altitude value. Before you begin ensure that your calibrated
and certified reference is set to the local pressure of 1013.25mB (29.92”Hg). The ALT-5 altitude value in ft (referenced to
1013.25mB (29.92”Hg)) is displayed in the top right hand corner of the display. All calibration must be done in feet.
The combined adjustments cater for both the altitude sensors offset and gain. Only start the calibration sequence once
the instrument has been running for a minimum of 10 minutes.
Start the altitude calibration with the “CAL FACTOR” and make sure the “CAL GAIN” value is set to 100.00%.

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Cal Factor:
This is the offset of the pressure sensor in 0.1mB increments. Adjust your static pressure to be close to sea level pres-
sure. The exact altitude is not important and can be up to several hundred feet. Adjust the calibration factor so the altitude
readout in the top right hand corner of the display agrees with your pitot static test set.
Cal ain:
Once you are satisfied that the low level altitude “CAL FACTOR” is correct apply a static pressure that will result in an al-
titude between 20000 and 30000 ft. Adjust the “CAL GAIN” until the altitude readout in the top right hand corner of the dis-
play agrees with your pitot static test set
N TE: Adjusting the “CAL GAIN” also changes the low level altitude calibration achieved when adjusting the “CAL FAC-
TOR”. Please recheck your low level altitude calibration and adjust if necessary. Recheck your altitude readout at the
higher altitude and if needed slightly adjust the “CAL GAIN” again. Repeat the process until you are satisfied with both
the “CAL FACTOR” altitude and the “CAL GAIN” altitude.
Tape:
Select the desired display tape (Altitude VSI or airspeed). The main display screen will change according to this selec-
tion.
Serial Out:
Select “ON” to enable the RS232 serial altitude output. This formatted serial RS232 message can be directly interfaced to
various RS232 serial input transponders. If a parallel Gillham output is required then a CNV-ALT can be purchased from
your MGL Avionics distributor to convert the RS232 output to a parallel Gillham output.
Prot:
Select the protocol of the serial RS232 output message. The protocol can be selected between GARMIN AT Magellan
Northstar / Garmin Trimble / Garmin MGL Avionics and Microair UAV. Please note that the baud rate is automatically ad-
justed according to which protocol is selected. The output format is as follows. The message contains the current pres-
sure altitude with a fixed reference to 1013.25mB (29.92 inches mercury). All protocols use 8 databits no parity and 1
stop bit. The message is outputted once a second.
Protocol Baud
Rate
Message format Example
Garmin AT 1200 #AL space +/- five altitude digits right jus-
tified zero padded T+25 checksum car-
riage return
The checksum is a simple modulo 256 sum
of the binary values of the individual char-
acters. The checksum is sent as two char-
acters in hexadecimal format
#AL +02372T+25DF[CR]
Magellan 1200 #MGL +/- five altitude digits right justified
zero padded T+25 checksum carriage re-
turn
The checksum is a simple modulo 256 sum
of the binary values of the individual char-
acters. The checksum is sent as two char-
acters in hexadecimal format
$MGL+02372T+2513[CR]
Northstar
Garmin
4800 ALT space five altitude digits right justified
zero padded carriage return
ALT 02372[CR]
Trimble
Garmin
9600 ALT space five altitude digits right justified
zero padded carriage return
ALT 02372[CR]
MGL Avionics 9600 ALT +/- five altitude digits right justified
zero padded 1013.25mB (29.92”Hg) refer-
enced C +/- five altitude digits right justi-
fied zero padded (corrected to local pres-
ALT+02372C+02372L1013+0000XCA[
CR]

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sure) L local pressure setting in millibars
+/- four digit VSI reading right justified zero
padded in ft/min X checksum carriage re-
turn
The checksum is a simple modulo 256 sum
of the binary values of the individual char-
acters. The checksum is sent as two char-
acters in hexadecimal format
Microair UAV 9600 STX a = five altitude digits right justified
zero padded ETX
[STX]a=02372[ETX]
Infiniteq 57600 See Infiniteq protocol format below
STX=0x02
ETX=0x03
CR=0x0D
Infiniteq protocol format:
STX, Address, Message type, Length, Data payload, Checksum, ETX
STX: Start of text (0x02)
Address: unsigned char (8bit) (0x01)
Message Type: unsigned char (8bit) (0x06)
Length: unsigned char (8bit) Length of the data payload (does not include the STX Address message type checksum or
ETX) (0x0e)
Data payload:
Altitude: Signed Long (32 bit) Altitude in feet (Referenced to 1013.25mB)
Altitude: Signed Long (32 bit) Altitude in feet (Corrected to local pressure)
Local Pressure: Unsigned Int (16 bit) Local pressure setting in millibars
Vertical Speed: Signed Int (16 bit) Vertical Speed in ft/min
Airspeed: Unsigned Int (16 bit) Airspeed in mph
Airspeed: Unsigned Int (16 bit) Airspeed in mph
Checksum: unsigned char (8bit) XOR of all bytes starting from the unit address to the end of the data payload. The
checksum is seeded with 0xa5. (does not include the STX or ETX)
ETX: End of text (0x03)