Marshall Amplification Field Marshall 100 Owner's Manual page 26

Field Marshall Tracking Receiver
Rule #2:
Whenever you take a new bearing with your yagi,
scan the entire horizon first, all 360 degrees. Otherwise you
could find yourself following the back lobe, going exactly the
opposite direction from your animal.
The Field Marshall antenna provides the best combination of gain
and sharp pattern possible in a 3 element yagi. Your Marshall
receiver can be used with other antennas in addition to the built-in
Antenna. A car-mounted 5 or 7 element yagi is an excellent
antenna for long distance telemetry.
Omni-directional an-
tennas
These antennas pick up
equally well in all directions.
You should use one in your
vehicle when moving to the
next point where you'll take a
bearing. Hearing the signal
from your animal can tell you
if you're going in the right di-
rection and warn you if you're
about to lose the signal.
Yagi Tips
Don't touch the elements while using it. Keep it away from other
objects, especially cars and other people. Don't substitute other
lengths of coax. The gain of your antenna can change if you raise
it up or down, so keep it at a fixed height as you scan (higher is
generally better.)
In spite of the above guidelines, a yagi is very forgiving. It will
almost always guide you directly to your lost animal, hopefully
awaiting your appearance.
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