Transcript Document

PJ2T
Flag Receiving Antenna
SIGNALS
ARRIVAL
There is a free-floating
egg insulator at each
corner
29’
6
Guy
ring
5
The flag is constructed with two lengths of #14 wire (top and
bottom), each 43 feet long. They are each soldered to the 18:1
transformer at one end, and through the 910-ohm resistor on the
other end, with an egg insulator included for strain relief. Total
length of wire required is 86-feet.
6
~900-ohm
18:1
resistor
transformer The vertical wire section is 14-feet long, and start 6-feet above the
ground. There is a sliding end insulator at each corner.
5
Guy ring
The feed transformer and terminating resistor are each anchored
to the mast 13 feet above ground.
14’
4
23.75”
22’
3
18’
RG-8X
2
The 18-foot RG-8X feedline connects to the transformer, then is
taped to the mast below the feedpoint and run to the ground. It
connects to the preamplifier, which in turn is connected to a 50foot length of RG-8X wound 8 turns around four FT240-31 ferrite
cores in a 1.5-foot coil.
Each fiberglass mast section is 44 inches high when stacked, and
the 6-section masts are 22-feet high. Each mast section is
numbered (1-6). They are 30 feet apart, and are guyed at the top
of the fourth fiberglass mast section (14’ 8” off the ground). Each
of the six guy ropes must be at least 25-feet long, but are cut to
40-feet to allow guying onto random bushes as available.
29’
21.5”
4
Guy rope
>25-feet long
23.75”
3
2
27”
6’
1
44”x 6 Fiberglass Mast Sections
Preamplifier
8 turns on four (4)
FT240-31 toroids
1
K8ND 070109a
PJ2T
Flag Receiving Antenna
Feed Details
RG-8X Feedline, 18-feet. Tape to
mast, from feedpoint to ground.
Wire
18:1
transformer
RG-8X Feedline to shack,
with +12V for preamplifier
Choke: 8 turns RG-8X
through four FT240-31 ferrite
cores.
ECP-1 10 dB
Preamplifier
Wire
Fiberglass
Mast
Tape Feedline to
mast near ground.
The 18:1 matching transformer and the 10dB gain remote ECP-1 preamplifier system are products of Lance
Johnson Engineering (http://www.lancejohnsonengineering.com/ECP-1.html). Any 18:1 pennant/flag matching
transformer or preamplifier may be used. A preamplifier is required, as these antennas are deaf without one.
K8ND 070109a
PJ2T
Flag Receiving Antenna
Block Diagram
18:1 Transformer
(On Mast)
18-feet RG-8X down mast
to ground.
ECP-1 Preamplifier
(On Ground)
8-turn coaxial choke
on four FT240-31
ferrite cores.
~550-feet RG-8X
NOTE: This feedline has
+12 Volts on it for the
preamplifier.
+12 VDC
ECP-1 Power Box
(In Shack)
K1FZ KB-4
50-Ohm Splitter
(In Shack )
K8ND 070108a