Butternut HF9V User manual

831 N Central Ave Wood Dale IL 60191-1219 Tel: [phone] Fax: [phone] e-mail: [email protected] http://www.bencher.com
00408IZV 100700-1-
Instructions
Model HF9V
WARNING: DO NOT INSTALL THE ANTENNA WHERE ANY PART
OF IT CAN COME INTO CONTACT WITH POWER LINES IN THE
EVENT OF STRUCTURAL FAILURE, DURING INSTALLATION OR
IN THE COURSE OF NORMAL FLEXING AFTER INSTALLATION
FOR SUCH CONTACT CAN RESULT IN DAMAGE TO PROPERTY,
BODILY INJURY OR EVEN DEATH!
WARNING: IN NO CASE SHOULD THE ANTENNA BE INSTALLED
WHERE STRUCTURAL FAILURE OF ANY PART OF THE
ANTENNA OR ITS SUPPORTING SYSTEM CAN ENDANGER
PERSONS OR PROPERTY.
CAUTION! A GROUNDED ANTENNA WILL BE AT D.C. GROUND
POTENTIAL! TO AVOID THE DANGER OF SHOCK CONNECT ALL
STATION EQUIPMENT TO A GOOD EARTH GROUND. IT IS ALSO
RECOMMENDED THAT ALL STATION EQUIPMENT BE
DISCONNECTED FROM THE POWER MAINS BEFORE
CONNECTING THE FEEDLINE TO THE ANTENNA. PLEASE
CONSULT THE A.R.R.L HANDBOOK OR OTHER REFERENCE
MANUALS FOR ADDITIONAL SAFETY PROCEDURES WHEN
WORKING WITH ELECTRICAL EQUIPMENT.
NOTE: PLEASE READ ALL INSTRUCTIONS THOROUGHLY BEFORE
PROCEEDING TO ASSEMBLY.
NOTE: HIGH PERFORMANCE BUTTERNUT VERTICAL ANTENNAS
REQUIRE A RADIAL SYSTEM FOR ALL INSTALLATIONS.
Butternut offers three systems for installing vertical antennas:
Model GRK Ground Radial Kit for ground mounting—160 thru 6 meter operation
Model RMK-II Roof Mounting Kit for roof mounting—80 thru 6 meter operation
Model CPK Capacitive Counterpoise Kit for compact installations below 25 ft
(7.6 m) above the earth—80 thru 6 meter operation
Please refer to TECH NOTES—GROUND/RADIAL SYSTEMS, at the end of this
instruction, for other mounting schemes and assistance in designing your own
radial system.

-2-
REQUIRED TOOLS
Flat blade screwdriver and pliers. A 1/4", 11/32" and 3/8" nut driver will be
helpful.
ASSEMBLY
Refer to the appropriate diagrams and proceed as follows:
1. Check to be sure that all parts are present.
2. Install tube w/insulator (A) per instructions packaged with mounting system or
Tech Notes Ground/Radial Systems.
NOTE: A small packet of anti-seize/anti-oxide compound (Butter-
It’s-Not™) will be found inside tube w/insulator (A). This
compound should be applied lightly to each tubing joint and to
the inside of all clamps that must make good electrical contact
with the tubing sections.
3. Locate tube (B) and tube (B1). Slide the insulator end of tube (B1) into the end
of tube (B) with hole located 1/4 in (6.4 mm) from the end of the tube. Pass a
# 8 x 1 1/2" screw through both parts and secure with a lock washer and hex
nut.
4. From the center of the insulator, measure downward to a point that is 13 in
(33 cm) along tube (B) and make a pencil mark.
5. From the center of the insulator, measure upward to a point that is 9 3/8"
(23.8 cm) along tube (B1) and make a pencil mark.
6. Locate coil assembly 80/40 meter (C) and slide the clamp at the outer end of
the larger 80 meter coil over tube (B1), lowering the entire assembly until the
middle clamp can be positioned around the insulator between tube (B) and
tube (B1).
NOTE: The middle clamp may have to be pulled open slightly to
pass the bolt that goes through tube (B1) and the insulator.
7. Position the center coil clamp of coil assembly 80/40
meter (C) in the center of the insulator between tube (B)
and tube (B1). Pass a #10 x 1" screw through the clamp
as shown. Secure with a flat washer, lock washer and
wing nut.

-3-
ASSEMBLY
NOTE: The outer tab of this clamp may be bent back slightly to
provide clearance for the bolt, bending it back into place after
assembly.
8. Stretch the 40 meter (smaller) coil on the coil assembly 80/40 meter (C) until
the top of the upper clamp is even with the upper mark. Secure with a #10
flat washer, lock washer and wing nut.
9. Stretch the 80 meter (larger) coil on the coil assembly 80/40 meter (C) until
the bottom of the lower clamp is even with the lower mark. Secure with a
#10 flat washer, lock washer and wing nut.
10. Locate the capacitor assembly 80/40 meter (D) and install capacitor bracket
80 meter (D1) on the larger 200 pF capacitor using the installed screw.
NOTE: DO NOT USE EXCESSIVE FORCE OR OVER TIGHTEN THE
SCREWS ON EITHER CAPACITOR AS YOU WILL DAMAGE THEM.
DO NOT DROP THIS ASSEMBLY AS YOU MAY FRACTURE THE
CAPACITOR’S CERAMIC SHELL.
11. Locate capacitor bracket 40 meter (D2) and install on the smaller 67 pF
capacitor as above.
12. Install the above assembly onto the #10 screw protruding from the tab of the
center clamp on the coil assembly 80/40 meter (C). Align capacitor bracket
80 meter (D1) alongside the larger 80 meter coil of coil assembly 80/40 meter
(C). Secure with a #10 flat washer, lock washer and hex nut.
13. Attach the tab end of capacitor bracket 80 meter (D1) to tube (B) with
capacitor bracket clamp and secure with # 8 x 1" screw, lock washer and a
hex nut.
14. Attach the tab end of capacitor bracket 40 meter (D2) to tube (B1) as above.
15. Insert the un-slotted end of tube (E) into tube (B1) and secure with a # 8 x 1
1/2" screw, lock washer and hex nut.
16. Locate coil support tube 30 meter (O) and measure to a point 9 7/8 in (25.1
cm) down from the plastic insulator. Mark this point with a pencil.
17. Locate coil support tube 30 meter L bracket (O1) and place the tabbed end
inside of the coil support tube 30 meter (O) securing it with a # 8 x 3/4"
screw, lock washer and hex nut.
18. Place a #10 washer, lock washer and wing nut on the lower single clamp of

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ASSEMBLY
coil/capacitor assembly 30 meter (P).
19. Place a #10 washer, lock washer and hex nut on both upper clamps of
coil/capacitor assembly 30 meter (P).
20. Pass the lower single clamp of coil/capacitor assembly 30 meter (P) over the
insulator end of coil support tube 30 meter (O) and slide the coil downward
along the tube until the upper edge of the upper clamp is flush with the end of
the insulator. Align the upper clamp with the coil support tube 30 meter L
bracket (O1) and tighten the hex nut.
21. Stretch the coil until the bottom of the bottom clamp on the coil/capacitor
assembly 30 meter (P) is even with the mark on coil support tube 30 meter (O)
and tighten the wing nut.
22. Slide the remaining clamp from the above assembly over tube (E) and position
it so the coil support tube L bracket (O1) is even with fourth turn, counting
from the top of the 40 meter coil on the coil assembly 80/40 meter (C) and
tighten the hex nut.
23. Hook the coil support tube 30 meter L bracket (O1) around the fourth turn of
the 40 meter coil on coil assembly 80/40 meter (C). Secure with a # 8 x 3/4"
screw, lock washer and hex nut.
24. Attach strip 17 meter (X) to the bolt that fastens the coil to the plastic
insulator between the coil and the upper clamp of the Coil Assembly 17 Meter
A-17-12 (W). Use the attached flat washer, lock washer and hex nut.
25. Attach the strip 12 meter (Z) to the coil assembly 12 meter A-17-12 (Y) in the
same way.
26. Loosen the #10 hex nut on the bottom clamp and the wing nut on the upper
clamp of coil assembly 17 meter A-17-12 (W) and slide the assembly over the
upper end of tube (E) with the insulator end up.
27. Slide the unit down until the lower clamp of the coil assembly 17 meter A-17-
12 (W) rests on the upper clamp of the coil/capacitor assembly 30 meter (O).
28. Tighten the hex nut and stretch the coil so that the distance between the
upper edge of the lower clamp and the lower edge of the upper clamp is 10
1/2 in (26.7 cm).
29. Install the coil assembly 12 meter A-17-12 (Y) in the same way, so the lower
edge of the lower clamp is about 2 in (5.1 cm) above the upper clamp of the
coil assembly 17 meter A-17-12 (W). This distance is not critical.

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ASSEMBLY
30. Tighten the hex nut and stretch the coil so that the distance between the
upper edge of the lower clamp and the lower edge of the upper clamp is 8 3/4
in (22.2 cm).
31. Position wire clamp 0.875" 15 M w/insulator (K) around tube (F) and use a # 8
x 1" screw, lock washer and hex nut finger tight.
32. Slide wire clamp 0.875" 6 M w/insulator (V) around tube (F).
33. Insert the un-slotted end of tube (G) into the slotted end of tube (F) and secure
with a # 8 x 1 1/4" screw, lock washer and hex nut.
34. Position wire clamp 0.750" 6 M w/insulator (U) around tube (G).
35. Locate wire clamp 0.750" 15 M w/insulator (N) and position it around tube (G).
36. Insert the un-slotted end of tube (H) into the slotted end of tube (G) and secure
with a # 8 x 1" screw, lock washer and hex nut.
37. Position wire clamp 0.625" 6 M w/wire (T) around tube (H) so the top edge is
33 1/4 in (84.5 cm) from the upper end of the tube.
38. Pass the free end of the stranded wire from wire clamp 0.625" 6 M w/wire (T)
through the small hole in wire clamp 0.750" 6 M w/insulator (U).
39. Line up and position the bottom edge of wire clamp 0.875" 6 M w/insulator (V)
58" (1.5 m) from the upper edge of wire clamp 0.625" 6 M w/wire (T) and
tighten.
40. Pass the free end of the stranded wire from wire clamp 0.625" 6 M w/wire (T)
through the small hole in wire clamp 0.875" 6 M w/insulator (V). Loop the
free end of the wire around itself. Do not cut off the excess.
41. Center and align wire clamp 0.750" w/insulator (U) and tighten.
42. Locate wire clamp 0.625" 15 M w/insulator (M) and position it around tube
(H).
43. Insert the un-slotted end of tube (I) into the slotted end of tube (H) and secure
with a # 8 x 1" screw, lock washer and hex nut.
44. Position wire clamp 0.500" 15 M w/wire around tube (I) so the top edge is
13.5 in (34.3 cm) from the upper end of the tube and on the opposite side
from the 6 meter assembly.

-6-
ASSEMBLY
45. Measure from the rivet of wire clamp 0.500" 15 M w/wire (L) to a point 11 ft
3 in (3.4 m) along the stranded wire and mark this point.
46. Pass the free end of the stranded wire from wire clamp 0.500"
15 M w/wire (L) through the small holes in wire clamp 0.625"
15 M w/insulator (M) and wire clamp 0.750" 15 M w/insulator
(N) as shown.
47. Loop the end of the wire through the hole in wire clamp 0.875"
15 M w/insulator (K) sliding it on tube (F) until the mark on the
wire appears. Wind the wire back on itself. Do not cut off the excess wire.
48. Line up wire clamp 0.875" 15 M w/insulator (K), wire clamp 0.750" 15 M
w/insulator (N) and wire clamp 0.625" 15 M w/insulator (M) with wire clamp
0.500" 15 M w/wire (L) and tighten all clamps making sure the wire is
moderately taut but not enough to cause the upper tubing section to bow.
49. Place the protective cap on one end of tube (J).
50. Slide the uncapped end of tube (J) into the slotted end of tube (I) until only 25
in (63.5 cm) extends and secure with compression clamp small adjustable.
NOTE: In the following steps the antenna will be assembled and
raised to its full vertical height. If the antenna is to be installed in
an elevated position where it is unsafe or inconvenient to make
in-place adjustments, the antenna may have to be installed in one
piece. It will probably be necessary to raise and lower it and its
supporting structure a number of times to arrive at the ideal
adjustment on all bands. If so, every precaution should be
observed in order to avoid possible contact with power lines and
to prevent structural failure that can cause injury to persons or
property.
51. Place the lower end of tube (B) through tube (E) over the insulator on tube (A)
w/insulator. Line up the holes and secure it with a # 8 x 2" screw, lock
washer and hex nut.
WARNING: AVOID POWER LINES!
52. Raise the assemble of tube (F) through tube (J) and slide the lower end into
tube (E) fastening it securely with a # 8 x 1 1/4" screw, lock washer and hex
nut.

-7-
ASSEMBLY
53. Install coax 75 ohm matching (R) as shown placing the lug from the center
conductor over the screw on tube (B) and the braid over the screw on tube
w/insulator (A).
54. Place # 8 washers over each screw and install coil (Q) base matching. Secure
with washers, lock washers and hex nuts.
NOTE: Attach radials and ground to tube w/insulator (A) using the
remaining # 8 hardware.
WARNING: MAKE SURE THAT THE STATION EQUIPMENT IS
CONNECTED TO A GOOD EARTH GROUND! DO NOT HANDLE
CABLE CONNECTED TO STATION EQUIPMENT WITHOUT FIRST
DISCONNECTING THE EQUIPMENT FROM THE POWER MAINS.
YOU COULD BE ELECTROCUTED!
55. Connect coax 75 ohm matching (R) to any length of 50-53 ohm coaxial cable.
Connector PL258 (S) is provided. Seal the connection with the small roll of
Konnector-Kote.
CHECKOUT AND ADJUSTMENT
The dimensions and coil settings given above should produce reasonably low
VSWR readings over the entire 10, 15, 20 and 30 meter bands and over at least
250 kHz of the 40 Meter band. Bandwidth on 80/75 meters should be at least 30
kHz for VSWR of 2:1 or less at the low end of the band and may be as much as
100 kHz at the high end of the band, depending on the efficiency of the ground
system used, greater bandwidth being associated with lossy ground systems. It
should be remembered that on those bands where the physical height of a vertical
antenna is less than a quarter wavelength, the earth (or the resonant radial system
in above-ground installations) will have a good deal to do with VSWR and antenna
tuning, bandwidth and overall performance.
Low VSWR by itself does not mean that a vertical antenna is operating efficiently,
and if low VSWR is obtained with no more than the usual quick and dirty ground
connection, it most likely means the opposite. In general, poor operation or
improper tuning of vertical antennas can usually be attributed to inadequate (or
even reactive) ground systems or to other vertical conductors in the vicinity of the
antenna. For these reasons it is suggested that the antenna be placed as much in
the clear as possible and used with the best ground system that conditions permit.
For a more complete discussion of the interrelationships between vertical antenna
efficiency, bandwidth, VSWR, etc., a standard text such as the A.R.R.L. Antenna
Book is recommended. See also the material included at the end of these
instructions.

-8-
CHECKOUT AND ADJUSTMENT
For adjustment purposes a simple VSWR indicator may be used. More accurate
measurements may be made at the antenna (i.e., at the junction of the coax 75
ohm matching (R) and the main transmission line) than at the input end of the line,
but the tuning conditions that exist at the transmitter will usually be of greater
interest in that one's principal concern will be to couple power from the
transmitter into the transmission line.
1. Determine the frequency at which VSWR is lowest on 80/75 meters. The coil
setting given earlier should produce resonance and lowest VSWR at
approximately 3700 kHz. To raise the frequency of resonance of the lowest
VSWR, simply loosen the wing nut on the lower coil clamp of the coil
assembly 80/40 meter (C) coil on tube (B) and stretch the coil a bit more. To
lower the frequency, compress the coil. A 1 in (2.5 cm) change in the setting
of this coil will produce a frequency shift of approximately 125 kHz.
NOTE: Remember that the antenna tunes very sharply in this
range and that high values of VSWR may be encountered only a
few kHz either side of the lowest VSWR readings, so it would be
well to take VSWR readings every 25 kHz or so to avoid running
past the frequency of resonance and lowest VSWR.
NOTE: To minimize interference to other stations and to avoid
erroneous reading use only enough power to produce full-scale
deflection of the meter in the forward or r.f. out position.
2. Once the proper coil setting has been found for the desired band segment, coil
(Q) base matching at the base of the antenna may be adjusted for even lower
VSWR. If earth losses are moderate to high a good match may be possible if
coil (Q) base matching is left fully compressed; if earth losses are low (as with
an extensive radial system) coil (Q) base matching may have to be stretched
to twice its compressed length or more for a good match. In any case, a
single setting for coil (Q) base matching should suffice for operation over most
of 80/75 meters provided the 80 meter coil is readjusted for each different
band segment.
3. Determine the frequency of minimum VSWR on 40 meters. The coil setting
given earlier should produce resonance and lowest VSWR at approximately
7150 kHz. The 40 meter VSWR and resonance curve may be shifted in the
same manner as on 80/75 meters by changing the setting of the upper coil
clamp of coil assembly 80/40 meter. On this band the setting is much less
critical, and a 1 in (2.5 cm) change in the clamp setting will shift the VSWR
curve approximately 80 kHz. Be sure to loosen the clamp around tube (E) that
supports the 30 meter assembly and to reposition it as needed to avoid
distorting the 40 meter coil.

-9-
CHECKOUT AND ADJUSTMENT
4. Check VSWR on 20 meters. Tuning is quite broad on this band because the
antenna is physically much taller than a quarter wavelength. To raise the
frequency of the lowest VSWR, reposition the 30 meter assembly so that the
coil support tube 30 meter L bracket (O1) can be replaced on the next lower
turn of the 40 meter coil. Alternatively, to lower the frequency of lowest
SWR, reconnect the coil support tube 30 meter L bracket (O1) to the next
higher turn of the 40 meter coil. In some cases moving the tap point a full turn
up or down may cause more of a frequency shift than is desired, in which
case the entire 30 meter assembly may be rotated around tube (E) to permit
adjustments of less than one full turn.
5. Check VSWR on 15 meters. The VSWR curve may be shifted upward or
downward by changing the length of the stranded wire between wire clamp
0.500" 15 M w/wire (L) and wire clamp 0.875" 15 M w/insulator (K). To raise
the frequency, simply shorten the wire by wrapping a longer tail back on itself
and sliding the lower clamp upward to maintain tension. To lower frequency,
feed more of the tail back through the hole in the insulator to increase the
length of the wire between wire clamp 0.500" 15 M w/wire (L) and wire
clamp 0.875" 15 M w/insulator (K). A change of 2 in (5.1 cm.) will shift the
VSWR curve approximately 300 kHz.
6. Check VSWR on 10 meters. To raise the resonant frequency loosen the small
hose clamp over the slotted end of tube (I) and slide tube (J) farther into tube
(I); to lower the frequency, slide tube (J) farther out of tube (I) and retighten
the hose clamp. A length change of 3 in (7.6 cm) should move the VSWR
curve approximately 200 kHz.
7. Check VSWR on 30 meters. To raise frequency, loosen the wing nut on the
bottom coil clamp of coil/capacitor assembly 30 meter (P), stretch the coil and
retighten the wing nut. To lower frequency, compress the coil. A change of
only 1/4 in (6.4 mm) will shift the VSWR curve approximately 100 kHz. Large
changes in the setting of coil/capacitor assembly 30 meter (P) may affect 20
and 40 meter tuning, in which case it may be necessary to repeat steps 3 and
4. In general, the point at which the 30 meter coil taps on to the 40 meter coil
will be the major factor in 20 meter tuning.
8. Check VSWR on 17 meters. To move the SWR curve to a higher frequency
loosen the wing nut on the upper coil clamp and STRETCH the coil about 1/4 in
(6.4 mm) at a time. To move the SWR curve to a lower frequency range
COMPRESS the coil a like amount.
9. Check VSWR on 12 meters. Stretch the 12 meter coil in increments of 1/4 in
(6.4 mm) or so to raise the resonant frequency, or compress the coil a like
amount to lower the resonant frequency.

-10-
CHECKOUT AND ADJUSTMENT
10. Check VSWR on 6 meters. To raise the frequency of the lowest VSWR,
shorten the length of the wire and to lower frequency increase the wire
length. Alternatively, the upper clamp and the entire 6 meter assembly may
be placed higher on the antenna to lower frequency or lower to raise it.
11. Adjustments for 40, 30, 20, 15, 17, 12, 10 and 6 meters should have little or
no effect on the previous adjustments for 80/75 meters, but a final VSWR
check for this band should be made as in step 1 above.
NOTE: In above-ground installations it will usually be found that
resonance and lowest VSWR occur at slightly higher frequencies
on all bands compared to ground-level installations. Therefore on
15 and 10 meters, where length adjustment is the means of
getting antenna resonance, it is recommended that the length of
the stranded-wire between wire clamp 0.500" 15 M w/wire (L)
and wire clamp 0.875" 15 M w/insulator (K) be increased
approximately 3 in (7.6 cm.) and that tube (J) be extended
approximately 6 in (15.2 cm.) beyond the original dimensions
given if any above-ground installation is contemplated. These are
merely recommended preliminary settings, for it is impossible to
indicate precise settings that will produce resonance or lowest
VSWR at a given frequency in all installations.
In the preceding steps it has been assumed that the antenna has been installed in
a more or less clear spot away from other vertical conductors such as TV antenna
feedlines, towers and masts, and that a minimal ground system (or a system of
resonant radials in the case of above-ground installations) has been installed.
If those fairly basic conditions have not been met it is likely that resonance and
low VSWR will be impossible on some or even all bands. One should bear in mind
that VSWR, even with a resonant antenna, will depend in large measure on local
ground conductivity, height above ground in the case of an elevated antenna, the
extent of the radial, counterpoise or other ground system used, and on other
factors over which the operator may have little or no control. Fortunately, the
evils of VSWR greater than unity have been grossly exaggerated in recent
decades, and the only practical difference between a VSWR of unity and one of,
say, 3:1 in the average case lies in the reluctance of modern equipment to deliver
full power into lines operating at the higher VSWR without the help of a
transmatch or other outboard matching device. Transmitters having so-called
broadband solid-state output circuits (no tuning or loading controls) may be
especially troublesome in this regard, whereas the older vacuum tube pi-network
transmitters can usually be adjusted for maximum output over a tuning range
where the VSWR does not exceed 2:l.

-11-
THEORY OF OPERATION
The first L/C circuit generates enough reactance to bring the whole HF9V to
resonance on 80 meters allowing it to act as a 1/4 8radiator. It also generates
enough capacitive reactance to produce another discrete resonance at about 11
MHz. The second, 40 meter L/C circuit generates enough reactance to resonate
the whole HF9V allowing it to act as a 1/4 8radiator. In order to minimize
conductor and I²R losses an 80 and 40 meters where the antenna is physically
shorter than a 1/4 8and thus operates with lower values of radiation resistance,
large-diameter self-supporting inductors and low-loss ceramic capacitors are
employed. Where the height of the HF9V is slightly greater than a 1/4 8on 30
meters, an L/C series tuned circuit taps onto the 40 meter coil for the extra
inductance to pull the earlier 11 MHz secondary resonance down to 10 MHz. At
the same time, a portion of the 40 meter coil is shorted out which allows the
circuit to resonate on 30 meters The addition of this circuit also produces
additional resonances at 14 MHz and 28 MHz. On 20 meters the entire radiator
operates as a 3/8 8vertical with much higher radiation resistance and VSWR
bandwidth than conventional or trapped antennas having a physical height of 1/4 8
or less. Because the 20 meter radiation resistance will be several times greater
than that of conventional vertical antennas, an electrical 1/4 8section of 75-ohm
coax is used as a geometric mean transformer to match the 100-odd Sof
feedpoint impedance on that band to a 50 Smain transmission line of any
convenient length. The HF9V operates as a slightly extended 1/4 8radiator on 15
meters, a 1/4 8stub decoupler providing practically lossless isolation of the upper
half of the antenna on that band. On 10 meters the HF9V becomes a 3/4 8
radiator with considerably greater radiation resistance and efficiency than 1/4 8
trapped types. On 17 and 12 meters the coils act as packets of reactance which
allow the entire radiator to operate as a 1/2 8or 5/8 8vertical. Capacitance for
these circuits comes from what exists between the windings, the windings and
the radiator and the capacitance hat. On 6 meters the vertical wire together with
the adjacent section of antenna form a short-circuited 1/4 8transmission line
which cancels current flow. At the lower, open end of the 1/4 8section a very
high impedance is created the effectively divorces the upper part of the antenna
leaving the lower section to radiate as a 3/4 8vertical.
ELECTRICAL AND MECHANICAL SPECIFICATIONS
Height (adjustable): 26 ft (7.9 m)
Shipping Weight: 14 lbs (6.3 kg)
Feedpoint Impedance: Nominal 50 ohms through included matching line.
VSWR at resonance: 1.5:1 or less all bands
Power rating: 2 kW PEP 75/80, 40, 20, 15, l0 meters; 800 W PEP 17, 12 meters;
500 W PEP 6, 30 meters
Wind loading area: 2.2 ft2(.2 m2)
Bandwidth for VSWR of 2:1 or less: 1 MHz 6 meters, entire band 10, 12, 15, 17,
20, 30 meters, 250-300 kHz 40 meters, 40-100 kHz 75/80 meters

-12-
GUYING
The HF9V is designed to survive winds of up to 80 mph (129 kph) without guying
in the absence of ice loading or heavy precipitation, but over a period of time it is
to be expected that frequent or even constant flexing or vibration will reduce the
chances for survival in winds that would not damage a newly installed antenna.
Therefore in areas of frequent or heavy winds a set of short non-conductive guys
should be used to reduce the stresses that wind loading will impart to the lower
sections of the antenna. In this connection, it should be noted that light nylon
twine is totally unsuitable as guying material because it has too much stretch per
unit length, although the heavier sizes of nylon rope (or even sash cord) may be
suitable if used in short runs. Polyethylene rope may be used, but because some
grades tend to deteriorate fairly rapidly, periodic inspection should be made. A
single set of guys placed just above the 30 meter circuit will contribute greatly to
the stability and the longevity of the antenna, provided that the guys retain a slight
amount of slack and do not come off at too steep an angle. At Angles of less than
45/the guys begin to exert a downward compressive force on the structure that
can be more of a threat to survival than lateral wind loading on an unguyed
structure. Under no circumstances should guys be placed higher than one-third of
the way up the antenna. The upper two-thirds of the HF9V has little more than its
own weight to support, so these sections may be allowed to bend with the wind
with no serious risk of damage. It is the lower third of the antenna that must
support both the weight of the upper sections and the wind loading on them and
are thus more likely to receive damage in severe winds.

-13-
PARTS LIST
A00278SZV Tube A W/Insulator (1-1/8" X 24")
B00115BAV Tube B (1-1/8" X 48")
B1 00365SZV Tube B1 W/Insulator (1-1/8" X 12")
C00145SZV Coil Assembly 80/40 Meter
D290-07 Capacitor Assembly 80/40 Meter
D1 00150BAV Capacitor Bracket 80 Meter
D2 00220BAV Capacitor Bracket 40 Meter
E00123BAV Tube 1" x 48"
F00124BAV Tube 7/8" x 48"
G00125BAV Tube 3/4" x 48"
H00126BAV Tube 5/8" x 48"
I00127BAV Tube 1/2" x 48"
J00175BAV Tube 3/8" x 36"
K00286RZV Wire Clamp 7/8" 15 M W/Insulator
L00280RZV Wire Clamp 1/2" 15 M W/Wire
M00281RZV Wire Clamp 5/8" 15 M W/Insulator
N00282RZV Wire Clamp 3/4" 15 M W/Insulator
O00204SZV Coil Support Tube 30 M (1-1/8" X
9")O1 00176BAV Coil Support Tube 30 Meter L
Bracket
P00249SZV Coil/Capacitor Assembly 30 Meter
Q00137SZV Coil Q Base Matching
R290-08 Coax 75 Ohm Matching
S00228GZV Connector PL-258
T00331RZV Wire Clamp 5/8" 6 M W/Wire
U00332RZV Wire Clamp 3/4" 6 M W/Insulator
V00314RZV Wire Clamp 7/8" 6 M W/Insulator
W00503SZV Coil Assembly 17 Meter A-17-12
X00215BAV Strip 17 Meter
Y00258SZV Coil Assembly 12 Meter A-17-12
Z00216BAV Strip 12 Meter
HARDWARE
200077JZV # 8 x 3/4" Screw
500078JZV # 8 x 1" Screw
200079JZV # 8 x 1-1/4" Screw
200114JZV # 8 x 1-1/2" Screw
100109JZV # 8 x 2" Screw
16 00080JZV # 8 Lock Washer
600083JZV # 8 Flat Washer
16 00081JZV # 8 Hex Nut
100131JZV #10 x 1" Screw
700133JZV #10 Lock Washer
700132JZV #10 Flat Washer
300134JZV #10 Hex Nut
400135JZV #10 Wing Nut
100089FZV Protective Cap 3/8"
200143BAV Capacitor Bracket Clamp
100144JZV Compression Clamp Small Adjustable
.05 00050DZV Konnektor-Kote (1" x 8")

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Feedline Detail
PICTORIAL

-15-
TECH NOTES—GROUND RADIAL SYSTEMS
MOUNTING TUBE INSTALLATION
When tube w/insulator (A) is ground mounted, it should be protected against
corrosion if placed in concrete, damp acidic or alkaline soil. Asphalt roofing
compound, polyurethane varnish or other sealant that protects against moisture
may be used.
Concrete may be used in areas of high winds for greater strength, in which case
the post may be twisted slightly during setting for easy removal later.
Tube w/insulator (A) must be installed in a hole approximately 21 in (53.3 cm)
deep so that the upper end of the fiberglass insulator is approximately 7 in (17.8
cm) above ground level. Pack earth tightly around tube w/insulator (A) so that it
remains vertical.
NOTE: HAMMERING TUBE W/INSULATOR (A) INTO THE EARTH MAY CAUSE THE
INSULATOR TO SPLINTER. If the post must be hammered into the earth, protect
the end of the insulator with a block of wood
NOTE: DO NOT USE U-BOLTS TO ATTACH TUBE W/INSULATOR (A) TO A MAST,
TOWER ETC. U-BOLTS WILL EVENTUALLY CUT INTO THE TUBING AND
WEAKEN THE INSTALLATION. If U-bolts must be used, place a larger diameter
metal, such as the MPS Mounting Post Sleeve over tube w/insulator (A). Similar
precautions should be observed when using TV style towers with locking bolts.
The RMK-II Roof Mounting Kit includes the MPS as well as the STR-II Stub Tuned
Radial Kit.
GROUND MOUNTING
A vertical antenna in its simplest form, is electrically equivalent to
one-half of a dipole antenna stood on end. When the antenna is
mounted close to the ground, the earth below takes the place of the
"missing" half of the dipole. If ground conductivity is fair to good, a
short metal stake or rod may provide a sufficiently good ground
connection for resonant and low SWR operation on the bands for
which the antenna is designed. This basic arrangement is shown in
figure 1.
The way it works is that the capacitance between the vertical radiator and the
ground causes return currents to flow along the earths surface back to the
transmitter. If they have to come back along untreated lossy earth thy get back
to the source greatly attenuated. This return loss is like a resistor in series with
the antenna radiation resistance and will therefore affect the feed point
impedance.

-16-
TECH NOTES—GROUND RADIAL SYSTEMS
In almost every case the efficiency of a vertical antenna will be
greater if radial wires are used to improve ground conductivity as
in figure 2. It’s important to note that there’s no point in cutting
radials to any particular length when ground mounting because
the earth will detune them anyway. All you want to do is make
the surface of the earth around the antenna more conductive than
it is ordinarily.
If you can’t copper-plate the backyard, the best approach is to
run out as many radials as possible, each as long as possible
around the antenna in all directions. Radials may be left on top of the ground
however they should be buried for the sake of pedestrians and lawnmowers.
How long should radials be? A good rule is no shorter than the antenna is tall
because 50% of your losses will occur in the first 1/4 8out from the antenna. If
you have more than a dozen radials, they must be longer to get the most out of
them which is why the FCC specifies 113 wires each .4 8for AM broadcast
stations—the equivalent of a zero-loss ground plane. Obviously, for most ham
work this would be overkill.
In some cases wire mesh (i.e. chicken wire) may be used as a substitute for radial
wires and/or a ground connection, the mesh or screen acting as one plate of a
capacitor to provide coupling to the earth beneath the antenna.
It should be noted that a ground rod is useful only as a d.c. ground or as a tie point
for radials. It does little or nothing to reduce ground losses at r.f. regardless of
how far it goes into the ground.
Bare wire, insulated, any gauge, it doesn’t matter. The current coming back along
any one wire won’t amount to that much.
EFFICIENCY
The importance of reducing losses in the ground system can be seen from an
examination of a vertical antenna's feedpoint impedance which at resonance
consists of three components: antenna radiation resistance; conductor loss
resistance; and earth loss resistance. An unloaded quarter-wave vertical antenna
has a radiation resistance of about 35 ohms with negligible ohmic or conductor
loss, but ground loss resistance may be very great if no measures are taken to
reduce it, and in some cases ground loss R may even exceed the antenna radiation
resistance. These three components may be added together to arrive at the
feedpoint impedance of a resonant (no reactance) antenna. For the sake of
illustration, assume that the ground loss beneath a quarter wavelength vertical
antenna is 15 ohms, that conductor loss resistance is zero, and that the radiation

-17-
TECH NOTES—GROUND RADIAL SYSTEMS
resistance is the textbook figure of 35 ohms. The feedpoint impedance would
then be 15+0+35 = 50 ohms, and the antenna would be perfectly matched to a
50 ohm coaxial line. Since the radiation resistance is an index of the amount of
applied power that is consumed as useful radiation rather than simply lost as heat
in the earth or in the conductor, the radiation resistance must be kept as high as
possible in relation to the total feedpoint impedance for maximum efficiency.
Efficiency, expressed as a percentage, may be found by dividing the radiation
resistance by the total feedpoint impedance of a resonant antenna, so under the
conditions assumed above our vertical antenna would show an efficiency of 35/50
= 70%. As a vertical antenna is made progressively shorter than one-quarter
wavelength the radiation resistance drops rapidly and conductor losses from the
required loading inductors increase. A one-eighth wave inductively loaded vertical
would have a radiation resistance of something like 15 ohms and coil losses (or
trap losses for multiband antennas) would be in the range of 5 ohms. Assuming
the same value of ground loss resistance (15 ohms), the feedpoint impedance
would become 15 + 5 + 15 = 35 ohms and the efficiency would be
15/35=43%. From the above calculations it is clear that the shorter a vertical
antenna must be the less efficient it also must be for a given ground loss
resistance. Or to state the matter another way, more elaborate ground or radial
systems must be used with shorter verticals for reasonable efficiency. If the
ground loss of resistance of 15 ohms from the preceding example could be
reduced to zero ohms, it is easy to show that the efficiency of our one-eighth
wavelength loaded vertical would increase to 75%. Unfortunately, more than 100
radials each one-half wavelength long would be required for zero ground loss, so
lower efficiencies with shorter radials must usually be accepted for the sake of
convenience. In spite of their limitations, short vertical antennas over less than
ideal ground systems are often more effective DX performers than horizontal
dipoles which must be placed well above the earth (especially on the lower bands)
to produce any significant radiation at the lower elevation angles. Verticals, on
the other hand, are primarily low-angle radiators on all bands.
ABOVE GROUND (ELEVATED) INSTALLATIONS (rooftop, tower, mast. etc.)
The problem of ground loss resistance may be avoided to some extent by
mounting a vertical antenna some distance above the earth over an artificial
ground plane consisting of resonant (usually 1/4 8) radial wires. Four resonant
radials are considered to provide a very low-loss ground plane system for vertical
antennas at base heights of 1/2 8or more. This arrangement contrasts favorably
with the more than 100 radials for zero ohms loss resistance at ground level, and
since 1/2 8is only about thirty-five feet at 20 meters, very worthwhile
improvement in vertical antenna performance can be realized, at least on the
higher bands, with moderate pole or tower heights. At base heights below 1/2 8
more than four radials will be required to provide a ground plane of significantly
greater conductivity than the lossy earth immediately below the antenna: even so,

-18-
TECH NOTES—GROUND RADIAL SYSTEMS
a slightly elevated vertical with relatively few radials may be more effective than
a ground-level vertical operating over a larger number of radials if only because
the former is apt to be more in the clear. Resonant radial lengths for any band
may be calculated from the formula:
Figure 3 shows the basic ground plane system for elevated
verticals. Radials may slope downward as much as 45 degrees
without any significant effect on operation or performance.
Radials for different bands should be separated as much as
possible and the far end of each radial insulated from
supporting wires. Figure 4 shows a ground plane system that
uses four resonant radials for 40 meters, another set of four for
20 meters, and a third set for 10 meters. A separate set for
15 meters is not ordinarily required because the 40 meter
radials operate as resonant 3/4 8radials on that band. At the
lower heights the separate wires of this system may provide enough capacitance
to ground to permit low SWR operation on 80/75 meters as well, but it is probable
that at least one resonant radial will be required for low SWR on that band. It’s
important to note that cutting each conductor of rotator cable to a specific
frequency will not work unless you separate it, angling each conductor away for
most of its length because the longer ones will detune the shorter ones.
The 12-radial system of Figure 4 is a very good one, but it
requires at least 12 tie-off points. Butternut has developed a
multiband radial made of 300-ohm ribbon that resonates
simultaneously on 40, 20, 15 and 10 meters. Four such radials
offer essentially the same ground plane performance as the
system of Figure 4 but require only 4 supports. These multiband
radials plus additional wire for an 80 meter radial are available
separately (our STR-II kit) or as part of the Butternut roof
mounting kit (RMK-II).
There are times when physical restrictions will dictate the use
of fewer than four radials, and at least one manufacturer
recommends 2 radials per band, the radials for each band
running 180 degrees away from each other. A simpler (and no
doubt less effective) system is shown in Figure 5. Since only
one resonant radial is used per band the antenna will radiate
both vertically and horizontally polarized energy, and the pattern will not be
completely omnidirectional. For true ground plane action and predominantly
vertical polarization no fewer than three equally-spaced radials should be used.

-19-
TECH NOTES—GROUND RADIAL SYSTEMS
Figure 6 illustrates the
construction of a multi-band
radial which is resonant on
40, 20, 15 and 10 meters.
Good quality 300 ohm TV
ribbon lead should be used
(velocity factor is critical),
and the conductors should employ at least one strand of steel wire to support the
weight of the radial. Four such radials will be the practical equivalent of the
system shown in figure four for operation on 40 through 10 meters.
Regardless of the number of radials used in either elevated or ground level
systems, all radials should be attached to the ground connection at the antenna
feedpoint by the shortest possible leads. An elaborate radial system at ground
level, for example, cannot be used with a vertical antenna on a rooftop or on a tall
tower, for the length of the ground lead would effectively become part of the
antenna, thus detuning the system on most or all bands.
METAL TOWERS AND MASTS
If a metal mast or tower is used to support a vertical antenna all radials should be
connected to the mast or tower at the ground connection of the antenna feedline.
This is because one of the functions of a resonant radial is to detune a supporting
metal structure for antenna currents that might otherwise flow on the structure
and thus turn the vertical antenna system into a vertical long wire with unwanted
high-angle radiation.
OTHER MOUNTING SCHEMES
In cases where a resonant vertical antenna may neither be ground mounted nor
used with an elevated ground plane, operation may still be possible if connection
can be made to a large mass of metal that is directly connected or capacitively
coupled to the ground, e.g., central air conditioning systems or structural steel
frames of apartment buildings. Some amateurs have reported good results with
vertical antennas extended horizontally or semi-vertically from metal terraces
which serve as the ground connection. Alternatively, a quarterwave vertical may
be window mounted if a short ground lead to a cold water pipe or radiator can be
used. If a long lead must be used, tuned radials may be required for resonance on
one or more bands. Great care should be exercised in such installations to avoid
power lines and to keep the antenna from falling onto persons or property.
MOBILE HOME AND RV INSTALLATION
The principles of vertical antenna installations for use on mobile homes or RV's are
the same as for other installations, and they all boil down to two main
considerations. The first is that of erecting the vertical in the clearest possible

-20-
TECH NOTES—GROUND RADIAL SYSTEMS
spot, away from obstacles (including the MH or RV) that can interfere with
radiation from the antenna. The second is that of installing the beat possible
ground system beneath the antenna in order to minimize losses from r.f. currents
flowing in the earth below the antenna. Fortunately, the metal bodies of both MHs
and RVs can be used as highly conducting ground planes for vertical antennas in
exactly the same way that automobile bodies, etc., provide the ground system for
shorter vertical antennas for mobile operation. The metal body of an automobile,
MH or RV may be viewed as one plate of a capacitor. Since the surface area of
even a small automobile is quite large and in close proximity to the earth, its body
is tightly coupled to the earth below and may be considered simply as an
extension of the earth itself—a kind of hill as far as radio frequencies are
concerned, but one having higher conductivity than the earth itself. RVs and
especially MHs, having much greater surface area, will therefore provide a more
extensive and effective ground system than a large number of radial wires
occupying the same space as the MH or RV.
As in mobile installations, a vertical antenna may be mounted almost anywhere on
the body of the vehicle or MH and made to operate with reasonably low VSWR,
but it is generally considered that the best possible location for a mobile antenna is
in the middle of the roof of the vehicle, i.e., at the center of the vehicle's ground
plane and at a point where the antenna will not be in the "shadow" of any part of
the vehicle. It is not usually convenient, or even practical to install a relatively tall
vertical on the roof of an RV or MH for any number of reasons, so the next best
procedure would be to install a vertical antenna with its base at the same level as
the roof, preferably near the middle of one of the longer sides. The exact way in
which this may be done is a matter of convenience, but a short mast extending
from ground level to the roof of the MH and RV and placed alongside the building
or RV would provide a stable and sturdy support with a minimum of mounting
brackets and other modifications to the RV or MH. For portable operation such a
mast could simply be lashed alongside the RV with the base in a shallow hole in
the ground for additional support, and there would be no harm in extending the
mast a few inches above the roof level to permit attachment of ropes which could
be used to hold the mast firmly against the side of the vehicle and to prevent side
sway.
This system has been used successfully with various types of RVs, travel trailers
and even passenger automobiles during portable operation. For "L" shaped mobile
homes a vertical antenna should be placed in the corner of the "L" so that the
metal roof will provide groundplane coverage over 270 degrees.