Furuno SCX-20 User manual

Explaining the Roof Mounting the SCX20
Credit for correctly figuring this out goes to Furuno forum member Bill106. His Jinglish certification is top notice.
One seal goes on the underside of the SCX20 near the NMEA 2000 connection. Some of the units already have this
attached at factory. (fig 1) If not attached, you must put it into place. It is the smaller of the two seals. It is always used.
(roof or surface mounting)
The other is a rubber compression seal (fig 2) that sits UNDER the roof mount adaptor and compresses when the root
mount adaptor is pressed down to the roof/surface. This seal is normally placed around the antenna cable and into the
roof hole. This seal is not used when surface mounting. It only is used when the roof fixture is used. (roof mounting)
The smaller part of the seal goes into the hole at the top of the roof for which the roof adaptor sits on top of. Then the
roof fixture is screwed down the seal makes a tight seal.
The seals are very near the core/center of the unit.
You do not seal around the fixture. (fig 3) This area stays open so water can come and go. If you try to seal the base and
the roof adaptor it will create condensation and destroy your unit with water. The unit must be able to breathe.
Figure 1
Figure 2
Figure 3

It is okay and encouraged to put a bit of sealant on the screws, and the face of the seals, to assist with keeping the core
sealed tight, so that no water goes down into the console/area below. DO NOT seal around the base or around the
SCX20 unit.
Placement location in relation to other RF units on the boat is critical. Furuno installation manual and NMEA 0400
installation standards to be followed. Placement near strong RF sources or inside the transmitting radar beam will
reduce product life and/or damage the product.