Campbell Scientific TX312 High Data Rate GOES Transmitter - Manual (Page 41)

TX312 Transmitter
; Check number of times P126 has been executed unsuccessfully
; If P126 failed more than 3 times, give up and reset counter
11: If (X<=>F) (P89)
1: 42
X Loc [ Counter ]
2: 3 >=
3: 4 F
4: 30 Then Do
; Reset counter
12: Z=F (P30)
1: 0.0
F
2: 00 Exponent of 10
3: 42 Z Loc [ Counter ]
; Set P126 result code to zero, this will stop P126 from
; executing until the 4 hour transmit time comes around again.
13: Z=F (P30)
1: 0.0
F
2: 00 Exponent of 10
3: 41 Z Loc [ P126_RC ]
14: End (P95)
15: End (P95)
16: End (P95)
6. Field Installation
6.1 Field Site Requirements
The TX312 has two siting requirements for proper operation. The GPS
antenna must have a clear view of most of the sky. The transmission antenna
must have a clear view of the spacecraft. Other requirements are not specific
to the TX312, but are mentioned here anyway. The TX312 must be mounted
in an enclosure that will protect it from the environment, including
condensation. Most GOES systems are powered by a battery that is charged
by a solar panel. The solar panel must have a clear view of the southern sky.
Pay special attention to winter sun angles.
6.2 Transmission Antenna
The TX312 transmission antenna is a right-hand circular polarized Yagi with
11 dBic gain. 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.
The accuracy of the antenna aiming is not critical, but should be reasonably
good. As a guide, if the antenna is aimed 25 degrees off the spacecraft, the
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