a CH150 or CH200 regulator, BP12 or BP24 battery, and a solar panel typically can support these
requirements. For this power supply, the regulator connects to the TX325 power connector.
7.4 Transmission antenna
The TX325 transmission antenna is a right-hand circular polarized Yagi with 11 dBi gain. A bracket
is included with the antenna for mounting to a mast or pole. The antenna is directional and
should be aimed at the spacecraft. Both elevation and azimuth are unique to the location on the
planet and must be set. A poorly aimed antenna will cause a drop in signal strength or possibly
prevent successful transmission. As a guide, if the antenna is aimed 20 degrees off the spacecraft,
the received power will be half of a properly aimed antenna. Beyond 20 degrees, the received
power drops off quickly.
NOTE:
When attaching elements to the boom, make sure to place them such that the number of
grooves on the element equals the number of dimples on the boom. For example, the
element with four grooves should be placed at the spot on the boom with four dimples, and
so forth.
7.5 GPS antenna
The GPS antenna mounts to the end of a crossarm by using a 0.75-inch IPS threaded pipe and a
0.75-inch-by-1-inch Nu-Rail® fitting or CM220 mounting bracket. Mount the GPS antenna
above obstructions, but with the shortest cable possible. The GPS antenna will not receive GPS
signals through steel roofs, steel walls, or possibly concrete. Heavy foliage, snow, and ice will
attenuate the GPS signal. An unobstructed view provides better GPS performance resulting in
fewer ( or no) missed transmissions. Poor GPS antenna placement increases the number of
missed transmissions, and possibly stops all GPS transmissions.
7.6 Data logger programming
NOTE:
This section provides programming information for the GRANITE-series (≥OS 1), CR6 (≥OS
10), CR1000X (≥OS 4), and CR300-series (≥OS 10), data loggers. For information on
programming the CR3000, CR800-series, and CR1000 data loggers, refer to the example
program at
www.campbellsci.com/downloads/tx325-example-program-cr3000-cr1000-cr800
or contact Campbell Scientific.
TX325 Satellite Transmitter for GOES V2
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