Marshall Amplification Field Marshall 100 Owner's Manual page 18

Field Marshall Tracking Receiver
Why is the Range Sw itch necessary? My other re-
ceiver didn't have one.
The Range Switch is a feature that allows you to get a rough
idea of the distance to the transmitter.
If the signal is very strong and you don't switch down to Me-
dium or Near, the receiver will not point out the right direction
very precisely. The strong signal also saturates the receiver,
making all signals sound equally loud. This is common to all
receivers.
How can I tell how far aw ay m y transm itter is?
One of the biggest challenges in telemetry is determining dis-
tance. There is no scientifically sound way of getting the dis-
tance from a transmitter signal. You can easily be deceived by
a loud signal from a transmitter very far away. However, there
are a couple of tricks to estimating it:
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