MA8040V General Description:
The MA8040V is a self-supporting monopole-style vertical
for 80 and 40
meters. Parallel L/C resonators provide automatic bandswitching with full-band coverage from 7.0 – 7.3 MHz
and adjustable tuning to any 100-kHz segment between 3.5 – 4.0 MHz.
Heavy-duty loading coils and
resilient stainless capacitive hats
deliver high efficiency while handling up to 1500-Watts PEP.
Designed
especially for
DX operation, the radiation pattern provides a
low
launch angle to favor distant contacts and a
deep overhead null to cancel unwanted local QRM. The MA8040V weighs only 9 pounds for safe handling
and ease of installation.
Parts List:
Before assembling, read
manual thoroughly and check contents against the parts list below:
X
Quan.
Part # Description
[ ]
18
010009
5/8” x 8-32 screw
[ ]
1
010040
1-1/4” x 8-32 screw
[ ]
3
010123
1-1/2” x 8-32 screw
[ ]
2
010231
1-3/4” x 8-32 screw
[ ]
4
010120
2” x 8-32 screw
[ ]
1
014764
2-1/4” x 8-32 screw (Philips Head)
[ ]
45
010011
Hex nut, 8-32
[ ]
27
011941
Split lock washer, #8
[ ]
4
360941
Flat aluminum spacer washer, #10
[ ]
2
320056
Aluminum spacer, 1/4” x 5/16” OD
[ ]
10
100449
Star-locking solder lug
[ ]
2
194173
Small 90-degree aluminum bracket
[ ]
4
105630
1/2” x 1/4” OD loading coil standoff spacer.
[ ]
12
056249
Vinyl radial-rod cap
[ ]
1
055105
1/4” ID black vinyl tip cap
[ ]
4
030412
Large worm clamp
[ ]
3
030407
Small worm clamp
[ ]
1
MA8040VJ1
Formed jumper wire
[ ]
1
902428
Braid strap
[ ]
1
156336
1/2” ID tuning stub bushing
[ ]
1
MA8040VCA2
80-meter loading coil assembly
[ ]
1
MA8040VCA1
40-meter loading coil assembly
[ ]
4
226442
Stainless steel radial-rod stock, 0.1” X 25”
[ ]
8
226443
Stainless steel radial-rod stock, 0.1” X 31”
[ ]
3
194174
8-hole radial ring
[ ]
2
196242
Upper radial ring support bracket
[ ]
2
195393
Lower radial clip
[ ]
1
196230
Lower radial clip support bracket
[ ]
1
290326
Danger label
[ ]
1
296357
MA8040V Product Label
[ ]
1
096359
Radial wire kit (400’ spool, #18 solid enamel)
[ ]
1
126228
Fiberglass resonator support, 1” OD x 29-1/2’” tube
[ ]
1
126241
Fiberglass base insulator, 1.25” OD x 16” tube
[ ]
1
MA8040VBAT
Aluminum base radiator section-1, 1-3/8” OD x 36” tube
[ ]
1
MA8040VBB
Aluminum radiator splice section, 1-1/4” x 12” tube
[ ]
1
MA8040VBC
Aluminum radiator section-2, 1-3/8” x 72” tube
[ ]
1
MA8040VBD
Aluminum radiator section-3, 1-1/4” x 72” tube
[ ]
1
MA8040VBE
Aluminum radiator section-4, 1-1/8” x 72” tube
[ ]
1
MA8040VBAB
Aluminum base support section, 1-3/8” x 12” tube
[ ]
1
MA8040VBF
Aluminum resonator stub section-1, 1/2” OD x 23-7/8” tube
[ ]
1
MA8040VBG
Aluminum resonator stub section-2, 3/8” OD x 23-7/8” tube
[ ]
1
MA8040VBH
Aluminum resonator stub section-3, 1/4” OD x 23-7/8” aluminum rod
Step-16: Tune-up and test
Use a handheld SWR analyzer or
transceiver with SWR meter to set up the MA8040V. If your radio has an
auto tuner, turn it off while making adjustments. To lower the antenna for top-section adjustments without
disrupting ground radials, loosen worm clamp and separate sections 1 and 2 (see
Figure-16
below
)
.
[ ] 80
meters:
Adjust top section for minimum SWR at
center of desired 100-kHz segment.
Tuning may
vary with different ground conditions and depending on proximity of other conductors. For best SWR at low
end of
band, clamp hat rods for maximum extension from the radial ring to increase hat diameter (refer back
to
Step-10
Fig-10
). This setting lowers tuning range by 50 kHz. For best SWR performance at top of band or
MARS
coverage, set hat rods for minimum extension
and remove one rod. Removing a rod increases range
by 100- kHz).
Use
Graph-1
below as a guideline
for your initial resonator setting:
30"
36"
42"
48"
54"
60"
66"
72"
24"
3.5
3.6
3.7
3.8
3.9
4.0
Frequency MHz
Resonator
Length
Minimum Hat-Rod Extension
Maximum Hat-Rod Extension
Minimum Extension, 1 Rod Removed
Graph-1:
Suggested 80-meter Resonator Settings
[ ] 40
meters:
SWR should measures 2:1 or less across the entire 40-meter band with the 25” hat-rods
provided. Tuning the 80-meter resonator will have little or no impact on 40-meter tuning.
To lower antenna for tuning,
separate element at top
of first section.
Support antenna with saw horse,
small ladder, etc.
while adjusting.
Figure-16:
Handling antenna for tuning operation
Avoid tuning the MA8040V in wet weather—water droplets on coils and radiator surfaces will lower operating
frequency artificially and result in mistuning.