Cooling Air; Gtx 330 Installation - Garmin GTX 330 Installation Manual

2.4

COOLING AIR

The GTX 330 meets all applicable TSO requirements without forced air-cooling. The application of forced air
cooling to the rear air nozzle of the GTX 330 is highly recommended to provide beneficial cooling to the unit.
The GTX 330 was designed to handle a constant interrogation of 450 Pulse Repetition Frequency (PRF) per
second, with short periods of 1200 PRF. Rate limit is set at 1200 PRF. A typical radar site would interrogate the
transponder once every 5 to 10 seconds for approximately 100 milliseconds at a 400 PRF rate. In very high
traffic areas with multiple ground stations and TCAS traffic it is possible to have long term PRF rates above 450
PRF.
2.5

GTX 330 INSTALLATION

Avoid installing the unit near heat sources. If this is not possible, insure that
additional cooling is provided. Allow adequate space for installation of cables
and connectors. The installer will supply and fabricate all of the cables. All
wiring must be in accordance with FAA AC 43.13-1B and AC 43.13-2A.
1. Assemble the connector/rack kit according to Figure B-2. Install the rack assembly according to the
dimensions given in Figure B-1 and paragraph 1.6.2, Physical Characteristics. Mounting brackets are not
supplied due to the wide range of mounting configurations available. Suitable mounting brackets may be
fabricated from sheet metal or angle stock. To insure a sturdy mount, rear support for the unit must be
provided.
2. Looking at the bottom of the transponder, make sure the front lobe of the locking mechanism is in a
vertical position. This can be accomplished by using a 3/32" Allen wrench through the face plate.
3. Slide the unit into the rack until the front lobe of the unit touches the rack.
4. Turn the Allen wrench clockwise until unit is secured in the rack. Continue turning until tight. Do not
overtighten the screw.
5. To remove the unit from the rack, turn the 3/32" Allen wrench counterclockwise until it disengages from
the rack.
Page 2-4
Rev E
NOTE
GTX 330 Installation Manual
190-00207-02