Instruction manual

DDF1  33
and should be positioned to the right of antenna 1 as viewed from the center
of the antennas for a clockwise spin. Close and open S2 until the voltage on
terminal J2 pin 3 reads +1.4V. Pins 1,2, and 4 should all read near 0V. Pin 3
is the antenna enable signal for antenna 3 and should be positioned to the
right of antenna 2 as viewed from the center of the antennas. Close and
open S2 until the voltage on terminal J2 pin 4 reads +1.4V. Pins 1, 2, and 3
should all read near 0V. Pin 4 is the antenna enable signal for antenna 2
and should be positioned to the right of antenna 3 as viewed from the center
of the antennas.
RF Operation
Testing the RF operation of the antenna is quite simple. Place all four an-
tenna mounting boards around the center of the car roof, placing each an-
tenna at the corner of an 18.25 inch square pattern for operation on 146
MHz. Do not install any of the whip antennas yet. Connect the RF output of
the antenna switcher to your FM receiver or transceiver tuned to the fre-
quency desired.
CAUTION: MAKE SURE YOU DISABLE TRANSMIT MODE IF YOU ARE
USING A TRANSCEIVER!
Apply power to the RDF unit and open S2 to stop the spinning process. In-
stall a whip antenna on ONE of the antenna mounting boards. Using a low
power transmitter such as a portable handheld transceiver on low power,
walk a distance away from the antenna and transmit on the frequency your
receiver is tuned to. Only one antenna should provide a signal strength
reading similar to it being connected directly to the FM receiver. Remove the
whip from the selected antenna and touch it to each of the other three anten-
nas. The received signal should be weak or nonexistent. Close and open
S2 until another antenna is selected and repeat the same test. Continue the
process until you have verified each antenna can be turned on while the
other three remain off.