Trimble Outdoors SK8 - Manual (Page 30)

1-8 Lassen-SK8 Embedded GPS Module
Starter Kit
1.3 Antenna
The GPS antenna receives the GPS satellite signals and passes them to the receiver.
Because the GPS signals are spread spectrum signals in the 1575 MHz range and do not
penetrate conductive or opaque surfaces, the GPS antenna must be located outdoors with a
clear view of the sky. The Lassen-SK8 requires an active antenna. The received GPS
signals are very low power, approximately -140 dB, at the surface of the earth. Trimble's
active antennas include a preamplifier that filters and amplifies the GPS signals before
delivery to the receiver.
Trimble offers a variety of antennas for use with the Lassen-SK8. The compact magnetic
mount GPS antenna and integral cable supplied with the Starter Kit is ideal for portable
and mobile applications. A permanent, bulkhead mount antenna is also available. A
compact, pole-mount rooftop antenna is available for fixed-site installations. Refer to
Appendix F for mechanical outline drawings of the GPS antennas.
Figure 1-5. Magnetic Mount GPS Antenna
Figure 1-6. Hard Mount GPS Antenna