34. Glass insulators are not available; therefore, _____________ or
______________ can be used as emergency insulators when fabricating
expedient antennas.
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ANSWERS:
30.
copper, aluminum.
31.
divide, 2
32.
twisted together.
33.
L = 142 = 1.88
1.88
=
.94
.94
-
.70
=
.24 meters
75.5
2
34. wood, dry rope.
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30. IMPROVISING GROUND-PLANE ANTENNAS.
When your RC-292 or OE-254 is
inoperative or not readily available, a satisfactory expedient can be
fabricated from field wire and pieces of wood (Fig 39).
This expedient
antenna is omnidirectional and can be used with al FM radios.
Step 1.
Compute
quarter-wave
antenna
lengths,
and
prepare
four
lengths of wire.
Step 2.
Cut three spacers (must be of equal length to achieve 120
separation between ground-plane elements).
Step 3.
Prepare antenna transmission line and ground wires.
(Transmission line should not exceed 13 meters because of possible
energy losses.)
Step 4.
Assemble antenna (Fig 39).
Step 5.
Tie rope to insulator end of antenna, and suspend from a
tree limb at least 8 feet off the ground.
Step 6.
Connect the antenna to the antenna terminal.
Step 7.
Ground the radio set.
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