User's Manual

INSTALLATION AND MAINTENANCE MANUAL
Tsunami FAMILY
SPREAD SPECTRUM RADIOS
SEPTEMBER 1999
PAGE 3-22 SECTION 3: INSTALLATION & ADJUSTMENTS
Use the Factory Test Data Sheet shipped with your Tsunami terminal to
obtain the best estimate of your RSL.
Above 0 dBm RSL, the receiver may produce errors: however this level is rarely likely to be
exceeded. A link budget calculation should be made to calculate the anticipated RSL as described
in Section 3.3.3. During anomalous propagation conditions, the RSL may fade but will not
increase up more than 10 dB (except in unusual very long paths which may fade up by 15 dB).
Antenna alignment should enable the RSL to be peaked to the
level calculated in the link budget. If the RSL is peaked but is
approximately 20 dB below the calculated level, then it is likely
that the antennas are aligned on a sidelobe of the antenna's
radiated signal. In this case, the antennas should be rotated in a
wide arc until the main lobe is located. (Other possible causes of
low RSL are path obstructions, loss in connectors, adapters and
pigtail jumper cables or different antenna polarization at each end
of the link.)
Figure 3-6: Typical RSL Voltage versus Received Signal Level (RSL)