Garmin GA 38 Installation Instructions

Important Safety Information

⚠️ WARNING

See the Important Safety and Product Information guide in the GPS device product box for product warnings and other important information.

⚠️ CAUTION

To avoid possible personal injury, always wear safety goggles, ear protection, and a dust mask when drilling, cutting, or sanding.

ℹ️ NOTICE

When drilling or cutting, always check what is on the opposite side of the surface to avoid damaging the vessel.

This antenna can be installed to provide a stronger GPS signal to a compatible Garmin chartplotter. This antenna uses a BNC connector to connect to the port labeled ANTENNA or EXT GPS on a compatible Garmin chartplotter.

Antenna Mounting Considerations

⚠️ CAUTION

Do not install or store the antenna near strong magnets, including speakers. A strong magnetic field can damage the antenna.

You can mount the antenna on a flat surface or attach it to a standard 1 in. OD, 14 threads per inch, pipe-threaded pole (not included). You can route the cable outside of the pole or through the pole. For best performance, consider these guidelines when selecting the antenna mounting location:

• To ensure the best reception, the antenna should be mounted in a location that has a clear, unobstructed view of the sky in all directions (location 1).
• The antenna should not be mounted where it is shaded by the superstructure of the boat (location 2), a radome antenna, or the mast.
• The antenna should not be mounted near the engine or other sources of Electromagnetic Interference (EMI) (location 3).

The antenna should not be mounted near known ferrous metal objects such as a toolbox or compass.

If a radar is present, the antenna should be mounted above the path of the radar (location 4). If necessary, the antenna may be mounted below the path of the radar (location 5).

The antenna should not be mounted directly in the path of the radar (location 6).

The antenna should not be mounted within 1 m (3 ft.) of a VHF radio antenna or the path of a radar (location 7).

Testing the Mounting Location

1. Temporarily secure the antenna in the preferred mounting location and test it for correct operation.
2. If you experience interference with other electronics, move the antenna to a different location, and test it again.
3. Repeat steps 1-2 until you observe full or acceptable signal strength.
4. Permanently mount the antenna.

Surface Mounting the Antenna

ℹ️ NOTICE

If you are mounting the bracket on fiberglass with screws, it is recommended to use a countersink bit to drill a clearance counterbore through only the top gel-coat layer. This will help to avoid cracking in the gel-coat layer when the screws are tightened.

Before you permanently mount the antenna, you must test the mounting location for correct operation (Testing the Mounting Location, page 2).

1. Using the surface-mount bracket (1) as your mounting template, mark the three pilot-hole locations and trace the cable-hole in the center of the bracket.
2. Set the surface-mount bracket aside. Do not drill through the bracket.
3. Use a 3.2 mm (1/8 in.) drill bit to drill the three pilot holes.
4. Use a 25 mm (1 in.) drill bit or hole saw to drill or cut the cable hole in the center.
5. Use the included M4 screws and a Phillips screwdriver to secure the surface-mount bracket to the mounting surface. If the included M4 screws are too short, use M4 screws of appropriate length.
6. Route the cable (2) through the center hole, and connect it to the antenna.
7. Verify the large gasket (3) is in place on the bottom of the antenna, place the antenna on the surface-mount bracket, and twist it clockwise to lock it in place.
8. Use the M3 set screw and a 1.5 mm hex wrench to secure the antenna to the mounting bracket (4).
9. Route the cable away from sources of electronic interference.

Mounting the Antenna on a Pole

Mounting the Antenna with the Cable Routed Outside the Pole

Before you permanently mount the antenna, you must test the mounting location for correct operation (Testing the Mounting Location, page 2).

1. Route the cable through the pole-mount adapter (1), and place the cable in the vertical slot (2) along the base of the pole-mount adapter.
2. Screw the pole-mount adapter onto a standard 1 in. OD, 14 threads per inch, pipe-threaded pole (not included). Do not overtighten the adapter on the pole.
3. Connect the cable to the antenna.
4. Place the antenna on the pole-mount adapter and twist it clockwise to lock it in place.
5. Use the included M3 set screw and a 1.5 mm hex wrench to secure the antenna to the adapter (3).
6. With the antenna installed on the pole mount, fill the remaining gap in the vertical cable slot with a marine sealant (optional).
7. Attach the pole to the boat if it is not already attached.
8. Route the cable away from sources of electronic interference.

Mounting the Antenna with the Cable Routed Through the Pole

Before you permanently mount the antenna, you must test the mounting location for correct operation (Testing the Mounting Location, page 2).

1. Position a standard 1 in. OD, 14 threads per inch, pipe-threaded pole (not included) in the selected location, and mark the approximate center of the pole.
2. Use a 19 mm (3/4 in.) drill bit to drill a hole for the cable to pass through.
3. Fasten the pole to the boat.
4. Thread the pole-mount adapter onto the pole. Do not overtighten the adapter.
5. Route the cable through the pole and connect it to the antenna.
6. Place the antenna on the pole-mount adapter and twist it clockwise to lock it in place.
7. Use the included M3 set screw and a 1.5 mm hex wrench to secure the antenna to the adapter (1).
8. With the antenna installed on the pole mount, fill the vertical cable slot (2) with a marine sealant (optional).
9. Route the cable away from sources of electronic interference.

Mounting the Antenna Under the Deck

ℹ️ NOTICE

Before using the included screws to secure the under-deck mounting bracket, verify they are short enough to avoid penetrating through the surface. If necessary, purchase screws of the appropriate length.

Before you permanently mount the antenna, you must test the mounting location for correct operation (Testing the Mounting Location, page 2).

Because the antenna cannot acquire signals through metal, it must be mounted under a fiberglass surface only. The under-deck mounting kit is supplied with the white antenna models only.

1. Place the adhesive pads (1) on the under-deck mounting bracket (2).
2. Place the antenna in the under-deck mounting bracket.
3. Adhere the under-deck mounting bracket to the mounting surface.
4. Secure the under-deck mounting bracket to the mounting surface with screws.
5. Connect the cable to the antenna (3).
6. Route the cable away from sources of electronic interference.

Specifications

Limited Warranty

The Garmin standard limited warranty applies to this accessory. For more information, go to garmin.com/support/warranty.

Australian Purchases: Our goods come with guarantees that cannot be excluded under the Australian Consumer Law. You are entitled to a replacement or refund for a major failure and for compensation for any other reasonably foreseeable loss or damage. You are also entitled to have the goods repaired or replaced if the goods fail to be of acceptable quality and the failure does not amount to a major failure. The benefits under our Limited Warranty are in addition to other rights and remedies under applicable law in relation to the products.

Garmin Australasia, 30 Clay Place, Eastern Creek, NSW 2766, Australia. Phone: 1800 235 822.

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