FM100B
•
15
about 114 acres. A quick glance at stereo FM receiver specifications shows
typical sensitivity of 1.7 µV before considering high-gain antennas or
preamplifiers. Your non-licensed signal can provide serious competition to a
public broadcast station fifty miles away, a station which someone in your
neighborhood may have set up a special antenna to enjoy.
Calibrated "field strength meters" such as described in the ARRL Radio
Amateur's Handbook can detect signals down to about 100 microvolts. To
measure RF field strength below such a level, professional or laboratory
equipment and sensitive receivers are required. A "sensitive" receiver
responds to a signal of 1 or even .5 microvolt "delivered" to the receiver input
by antenna. If the antenna is not good, the receiver cannot respond to the
presence of fractions of a microvolt of RF energy.