Garrecht Avionik GmbH
VT-01 Transponder
Installation Manual - english -
Document:
01.0200.11E
Revision: 1.3
24
6.2.4.3. Power supply
The transponder is supplied by the aircrafts’s primary power source (10 V to 28 V DC). The system
provides a protection against reverse polarity.
Always install a fuse !!!
6.2.4.4. Suppression interface
The suppression line needs to be wired to other avionic components such as DME or TACAN to
suppress any replies from the transponder that void capabilty of such systems while operating.
The suppression line provides IN and OUT capability to prevent data transmission either to the
transponder or to other equipment.
Wiring the suppression line requires a qualified avionic technician or engineer
to prevent any kind of malfunction of the installed equipment. All equipment
connected to the suppression line must be re-inspected and re-approved before
operation. Refer to chapter 5 for specifications of the suppression interface.
6.2.4.5. On-ground interface
If your aircraft installation provides an on-ground signal, it should be connected to this pin. The
transponder replies only to discretely addressed Mode-S interrogations if the on-ground signal is
present. The permament emission of squitters will not be effected.
Refer to chapter 5.10 for logic table of this interface.
6.2.4.6. RS-232 interface
This interface is intended ADS-B applications. It may be used for connecting a GPS receiver to
broadcast the current position in the squitters.
Minimum recommended NMEA sentences are $GPRMC, $GPGGA, $GPGSA. The baud rate is 4800
bps.
6.2.4.7. CAN-Bus interface
The CAN-Bus interface is used for communication between steering unit and
central unit. If the two-block configuration will be installed, on each device a
resistor (120 Ohms) must be used for proper termination of the data bus. A
missing termination results in COMM-Error and malfunction.
For pinout refer to the wiring diagram shown on the previous page.
6.2.4.8. Antenna connection
Connect the antenna line to the connector in the craddle. When inserting the central unit into the
cradle, the antenna plug fits into the antenna socket of the cradle.
DO NOT POWER ON THE TRANSPONDER WITH THE ANTENNA
DISCONNECTED!!!
Damage to the RF unit caused by a disconnected antenna can be
determined by the manufacturer and is not covered by the manufacturers warranty.
