Cushcraft MA8040V Instructions

Assembly and Installation Instructions

Appendix 1: How to make a Current-Choke Balun using a Toroid Form:

A current-choke style balun may be used to prevent the antenna’s feedline from interacting with the antenna
and radial system. Best SWR performance was obtained with a choke similar to the one shown here

Feedline Choke

Use

RG-58 for low power or

RG-303 for high power

12 - 14 Turns coax on

2.4" OD Toroid Core

Amidon Associates

FT240-73

or

Fair-RIte

5977003801

3.5-4.0 MHz, 7.0–7.3 MHz
50-Ohms

1.1:1 typical at resonance
100 kHz on 80/75 meters, 300 kHz on 40 meters
23-27 feet (adjustable for 3.5 – 4.0 MHz coverage)

9.0 LB (4.1 kg.)
0 dBi @ 3.5 MHz, 2 dBi @ 7 MHz
Eight recommended (4 x 65’, 4 x 35’)

installed at the antenna base.

MA8040V Specifications:

Frequency Coverage:
Impedance:
SWR:
Bandwidth (2:1 SWR)
Height:
Weight:
Typical Gain:
Ground Radials:

Limited Warranty:

Cushcraft Corporation, 48 Perimeter Road, Manchester, New Hampshire 03103, warrants to the original
consumer purchaser for one year from date of purchase that each Cushcraft antenna is free of defects in
material or workmanship. If, in the judgment of Cushcraft, any such antenna is defective, then Cushcraft
Corporation will, at its option, repair or replace the antennas at its expense within thirty days of the date the
antenna is returned (at purchaser’s expense) to Cushcraft or one of its authorized representatives. This
warranty is in lieu of all other expressed warranties, and implied warranty is limited in duration to one year.
Cushcraft Corporation shall not be liable for any incidental or consequential damages which may result from
a defect. Some states do not allow limitations on how long an implied warranty lasts or exclusions or
limitations of incidental or consequential damages, so the above limitation may not apply to you. This
warranty gives you specific legal rights and you may also have other rights which vary from state to state.
This warranty does not extend to any products which have been subject to misuse, neglect, accident, or
improper installation. Any repairs or alterations outside of the Cushcraft factory will nullify this warranty.

48 Perimeter Road

Manchester, NH 03103

603-627-7877

FAX [phone]

SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE

Cushcraft MA8040V Dual-Band Vertical Antenna

80 – 40 Meter Vertical Monopole Antenna

956358_GF_AA

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:

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Quan.

18
1
3
2
4
1
45
27
4
2
10
2
4
12
1
4
3
1
1
1
1
1
4
8
3
2
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1

Part # Description

010009
010040
010123
010231
010120
014764
010011
011941
360941
320056
100449
194173
105630
056249
055105
030412
030407
MA8040VJ1
902428
156336
MA8040VCA2 80-meter loading coil assembly
MA8040VCA1 40-meter loading coil assembly
226442
226443
194174
196242
195393
196230
290326
296357
096359
126228
126241
MA8040VBAT Aluminum base radiator section-1, 1-3/8” OD x 36” tube
MA8040VBB
MA8040VBC
MA8040VBD
MA8040VBE
MA8040VBAB Aluminum base support section, 1-3/8” x 12” tube
MA8040VBF
MA8040VBG
MA8040VBH

5/8” x 8-32 screw
1-1/4” x 8-32 screw
1-1/2” x 8-32 screw
1-3/4” x 8-32 screw
2” x 8-32 screw
2-1/4” x 8-32 screw (Philips Head)
Hex nut, 8-32
Split lock washer, #8
Flat aluminum spacer washer, #10
Aluminum spacer, 1/4” x 5/16” OD
Star-locking solder lug
Small 90-degree aluminum bracket
1/2” x 1/4” OD loading coil standoff spacer.
Vinyl radial-rod cap
1/4” ID black vinyl tip cap
Large worm clamp
Small worm clamp
Formed jumper wire
Braid strap
1/2” ID tuning stub bushing

Stainless steel radial-rod stock, 0.1” X 25”
Stainless steel radial-rod stock, 0.1” X 31”
8-hole radial ring
Upper radial ring support bracket
Lower radial clip
Lower radial clip support bracket
Danger label
MA8040V Product Label
Radial wire kit (400’ spool, #18 solid enamel)
Fiberglass resonator support, 1” OD x 29-1/2’” tube
Fiberglass base insulator, 1.25” OD x 16” tube

Aluminum radiator splice section, 1-1/4” x 12” tube
Aluminum radiator section-2, 1-3/8” x 72” tube
Aluminum radiator section-3, 1-1/4” x 72” tube
Aluminum radiator section-4, 1-1/8” x 72” tube

Aluminum resonator stub section-1, 1/2” OD x 23-7/8” tube
Aluminum resonator stub section-2, 3/8” OD x 23-7/8” tube
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:

72"

66"

60"

54"

Resonator

Length

Graph-1: Suggested 80-meter Resonator Settings

48"

42"

36"

30"

24"

3.5 3.6 3.7 3.8 3.9 4.0

Frequency MHz

Minimum Hat-Rod Extension
Maximum Hat-Rod Extension
Minimum Extension, 1 Rod Removed

[ ] 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.