Raymarine C90w - Manual (Page 44)

Typical locations and GPS performance
Optimal GPS performance (above decks)
GPS performance af fected by prevailing conditions
Not recommended
D11537-1
Vessel construction
• GRP vessels. Unit can be mounted above and below decks.
Although the proximity of heavy structure such as a structural
bulkhead, or the interior of larger vessels may result in a reduced
GPS signal.
• Other constructions. GPS performance may be adversely
affected below decks. Seek professional assistance and consider
use of an external GPS antenna mounted above decks.
Prevailing conditions
The weather and location of the boat can affect the GPS
performance. Typically calm clear conditions provide for a more
accurate GPS fix. Vessels at extreme northerly or southerly latitudes
may also receive a weaker GPS signal. GPS antenna mounted
below decks will be more susceptible to performance issues related
to the prevailing conditions.
44 C-Series Widescreen installation