CUSHCRAFT R7 Instruction Manual

951420 (11/92)

R7
WARNING
THIS ANTENNA IS AN ELECTRICAL CONDUCTOR. CONTACT WITH POWER LINES CAN RESULT IN DEATH, OR SERIOUS INJURY. DO
NOT INSTALL THIS ANTENNA WHERE THERE IS ANY POSSIBILITY OF CONTACT WITH OR HIGH VOLTAGE ARC-OVER FROM POWER
CABLES OR SERVICE DROPS TO BUILDINGS. THE ANTENNA, SUPPORTING MAST AND/OR TOWER MUST NOT BE CLOSE TO ANY
POWER LINES DURING INSTALLATION, REMOVAL ORIN THE EVENT PART OF THE SYSTEM SHOULD ACCIDENTALLY FALL. FOLLOW
THE GUIDELINES FOR ANTENNA INSTALLATIONS RECOMMENDED BY THE U.S. CONSUMER PRODUCT SAFETY COMMISSION AND
LISTED IN THE ENCLOSED PAMPHLET.
Your Cushcraft R7 vertical antenna is designed and manufactured to give trouble free service. This antenna will perform as specified if the instructions
and suggestions in this manual are followed and care is used in the assembly and installation. When checking the components received in your antenna
package use the parts listed beside each diagram. There is a master parts list on page 2. If you are unable to locate any tube or component, check
the inside of all tubing. IMPORTANT: Save the weight label from the outside of the carton. Each antenna is weighed at the factory to verify the parts
count. If you claim a missing part, you will be asked for the weight verification label.
PLANNING
Plan your installation carefully. If you use volunteer helpers be sure that they are qualified to assistyou. Make certain that everyone involved understands
that you are the boss and that they must follow your instructions. If you have any doubts at all, employ a professional antenna installation company to
install your antenna.
LOCATION
Although the R7 will operate in almost any location, it will perform best if it is mounted vertically and located in the clear away from surrounding objects
such as buildings, trees, power lines, towers, guy wires, antennas and metallic objects. The R7 should not be attached to aground radial system. Failure
to heed these points will possibly degrade performance, detune the antenna and increase VSWR.
EXTREME CARE MUST BE USED FOR YOUR SAFETY. YOU MUST INSURE THAT WHILE THE R7|ISINOPERATION NEITHER PEOPLE ORPETS
CAN COME IN CONTACT WITH ANY PORTION OF YOUR ANTENNA INCLUDING THE COUNTERPOISE RODS. DEADLY VOLTAGES AND
CURRENTS MAY EXIST. ALSO, SINCE THE EFFECTS OF EXPOSURE TO RF ARE NOT FULLY UNDERSTOOD, LONG TERM EXPOSURE TO
INTENSE RF FIELDS IS NOT RECOMMENDED. THERE ARE SEVEN WARNING STICKERS WHICH MUST BE ATTACHED TO THE ENDS OF THE
COUNTERPOISE RODS AS SHOWN IN FIGURE 3.
MOUNTING
Your mast should be rigid and pointing straight up. Always use a mast at least 1.5 inches (3.8 cm) but not larger than 1.75 inches (4.5 cm) in diameter.
If you guy the mast, use non-conducting guy wires.
SYSTEM GROUNDING
Direct grounding of the antenna mastis very important. This serves as protection from lightning strikes and static buildup, and from high voltages which
may be present in the equipment attached to the antenna. A good electrical connection should be made to one or more ground rods directly at the base
of the antenna or mast using a least #10 AWG ground wire and non-corrosive hardware. For details and safety standards, consult the National Electrical
Code. You should also use a coaxial lightning arrestor. Cushcraft offers several different models, such as the LAC-1, LAC-2 or the LAC-4 series.
ASSEMBLY
Assemble your R7 by following steps 1 through 6. After assembling the antenna, verify all dimensions in figure 5 for accuracy. Then return to the
adjustment section below for final tuning.
ADJUSTMENT
The dimensions in figure 5 normally allow proper operation on all the bands. However, some variations may occur from one location to another.
Adjustments must be made from the bottom of the antenna to the top. Adjusting the antenna from top to bottom will not work. This is because the
settings at the top are severely affected by the adjustments at the bottom. The bottom section A of the antenna covers 10 meters, the next sections
cover 12, 15, 17, 20, and 30 meters while the top section F covers 40 meters.
We suggest measuring the VSWR of your antenna by using the SWR meter in your tranceiver. If your tranceiver does not have one, use a good
quality VSWR bridge for this application. We will begin with 10 meters since this is at the bottom of the antenna. Set your tranceiver at your favorite
frequency on 10 meters. Key the rig and check your VSWR. The R7 is extremely broadbanded on 10 meters and this section seldom needs
adjustment. If the VSWR is low enough (below 1.5:1) then move on to the 15 meter section B (12 meters is not adjustable). If the 10 meter VSWR is
not low enough, adjust the antenna as follows: Check several frequencies on 10 meters to find the frequency of lowest VSWR. If the frequency of
lowest VSWR is above your favorite frequency, lengthen dimension A (figure 5) by 1 inch (2.5 cm). This should lower the frequency of lowest VSWR
by 50 to 100 KHz. If the frequency of lowest VSWR is below your desired frequency, shorten dimension A (figure 5) by 1 inch (2.5 cm). Check your
desired 10 meter operating frequency again to see if the VSWR is less than 1.5:1. Repeat this procedure until the VSWR at your desired frequency
is low enough.
Continue this procedure by selecting your desired frequency on 15 meters and checking the VSWR there. Dimension B (figure 5) should be used to
adjust the VSWR on 15 meters. Remember to shorten this dimension to raise the frequency or lengthen it to lower the frequency.
The balance of the antenna should be adjusted in a like manner. The dimensions and the bands that they effect are shown in figure 5. On 10
through 20 meters 1 inch (2.5 cm) of change in length will change the operating frequency by 50 to 100 KHz. On 30 and 40 meters the change will

R7
be 15 to 25 KHz per inch (5 to 10 KHz/cm). When the antenna is completely adjusted, check all fasteners to be sure they are tight. Improving
VSWR's that are less than 2:1 will not noticeably improve station performance.
INSTALLATION
Following the guidelines in the location and adjustment sections above, place the antenna on its mast in its final operating location. If you plan to
install the antenna in a salty or corrosive environment, you may want to consider coating it with a clear marine varnish or equivalent after final
assembly and adjustment has been completed. Now connect your transceiver. If you have any difficulties, reread the information above and the
helpful hints below.
HELPFUL HINTS
* Try to locate your R7 as far away from TV antennas and their feedlines as possible. This will help to avoid overloading your television with RF.
* The dimensions recommended in figure 5 are based on mounting the R7 approximately 8 feet (2.4 meters) above the ground and 25 feet (7.5 meters)
from surrounding objects. Antennas installed with less clearance may require additional adjustments.
* Ifyou check the resistance across the coax connector on your R7 you will finda DC short. This is normal. It does not mean that the RF path is short
circuited. It is approximately 50 Ohms at your operating frequencies.
* High VSWR is sometimes caused by poor contact between the matching network and the counterpoise rods. Make sure that corrosion has not formed
on the jumper strap terminals. Check to insure the hardware is tight.
* Make sure that the counterpoise brackets are 1 inch (2.54 cm) above the antenna base and 1-3/4 inch (4.45 cm) below the radiator as shown on figure
1. The counterpoise is a frequency sensitive system. Changing its length will degrade the R7's performance.
* If your R7 is very close to your shack you may experience RF on the feedline. Try lengthening your feedline several feet, placing an RF ferrite bead
on the coax, winding the feedline on a toroid or winding the coax in a 10 turn coil 8 inches (20 cm) in diameter.
* Weather sealing the matching network is not necessary. We have provided a large hole near the coax connector to allow air to circulate through the
box and to keep it dry. Keep this hole clear to avoid difficulties caused by humidity and condensation.
* Long periods (30 seconds or longer) of key down operation, such as RTTY, at high power (over 1000 Watts) may damage your R7.
MASTER PARTS LIST
P/N DESCRIPTION QTY KEY PIN DESCRIPTION
Base Section Assembly, 1-3/8" x 48" (2.8 x 121.9 cm) 011941 #8 split lock washer
1-1/4" x 48" (3.2 x 121.9 cm) aluminum tube 050077 += 3/8" (.95 cm) black plastic cap
slotted one end 010079 8-32x 1/2" (1.27 cm) stainless steel machine screw
1-1/8" x 48" (2.9 x 121.9 cm) aluminum tube 010083 1/4-20 x 1-1/4" (3.2 cm) stainless steel machine screw
slotted one end 010084 1/4" (.63 cm) stainless steel split lock washer
1-1/8" x 9" (2.9 x 22.9 cm) aluminum tube slotted 010085 1/4-20 stainless steel hex nut
both ends 202296 = 7/8" x 3-3/4" (2.22 x 9.53 cm) radial clamp
1" x 14" (2.5 x 35.6 cm) aluminum tube slotted 203110 Mast mounting ring
both ends 050115 Vinyl connector boot
1/2" x 24" (1.3 x 61 cm) aluminum tube slotted 240116 — Silicone grease packet
one end 203119 = 7/8" x 5-3/8" (2.22 x 13.7 cm) radial clamp
3/8" x 24" (.9 x 61 cm) aluminum tube 010220 10-24 stainless steel hex nut
10/12 meter trap assembly 34-5/8" (88 cm) 010231 8-32 x 1-3/4" (4.44 cm) stainless steel machine screw
15 meter trap assembly 15" (38.1 cm) 010233 #10 stainless steel split lock washer
17 meter trap assembly 15-3/4" (40 cm) 030407 = 7/32" (.5 cm) stainless steel worm clamp
20 meter trap assembly 21" (53.3 cm) 030409 = 7/8" (2.22 cm) stainless steel worm clamp
TV5 30 meter trap assembly 23" (58.4 cm) 030410 _1"(2.54 cm) stainless steel worm clamp
030411 1-1/4" (3.17 cm) stainless steel worm clamp
XHR 3/16" x 36" (.4 x 91.4 cm) aluminum rod with #18 030412 1-1/2" (3.81 cm) stainless steel worm clamp
hole drilled mid point 290326 Warning label
MN7 Impedance Matching Assembly 902428 Jumper Strap
11 010011 8-32 stainless steel hex nut 902832 0.100" x 49" (.25 x 124 cm) stainless steel rod with
26 190026 = 7/8" (2.22 cm) formed aluminum bracket with #8 hole ball tip one end
28 190028 = Aluminum half washer
NMONDNM OOOH HSH KH FH HH HOO

R7
#1 - ASSEMBLE COUNTERPOISE BRACKETS
Assemble two brackets (96) leaving the nuts (11) loose (figure 1).
Make three sets like this. Attach two sets together around the base
insulator making the lower bracket assembly. Locate the lower
bracket assembly 1 inch (2.54 cm) above the base tube (figure 2).
Attach the two remaining brackets (96) you previously assembled
around the base insulator using bracket (119) as shown in figure 2.
Locate this upper bracket assembly directly above and touching the
lower bracket assembly. FIGURE 1
Key] PN | | esc. | SE TY
11 | 010011 HEX 21
(eo ae cee ae
41 | 011944 LOCK 21
[ome ee | ge |e
010079 MACHINE 8-32 x 1/2" 21
miaer | Om |e
ROD 3-3/4" x 7/8"
geT_—ES | praceet | (953x222 cm)
203119 ROD 5-3/8" x 7/8"
BRACKET (13.7 x 2.22 cm)
FIGURE 2
RADIATOR
UPPER BRACKET
96 ASSEMBLY
Slide upper assembly
down until it contacts
lower assembly
BASE INSULATOR
i
<—— LOWER BRACKET
ASSEMBLY

#2 - ASSEMBLE BASE SECTION
Attach the Impedance Matching Assembly (MN7) to the radiator FIGURE 3
bracket (figure 3). To do this you may have to rotate the counter- epi
poise bracket assemblies (figure 2) slightly if they are in the way. i
Note that the half round bracket (119) in the upper assembly must gp 41
be directly behind the MN7. Holding the box with the pre-attached H
bracket on the bottom and next to the base tube, lift the box so that S : RADIATOR
the mounting bolts on the top of the box go through the holes in the BRACKET
\
()
NN
Nl
f
ta
SILICONE
© ch
2200 fit" @a1
| ' DO NOT COAT
6) 11 CENTER PIN
WITH SILICONE!
115
83 84 85
Oversized connector hole
on the bottom of MN7 is
for drainage.
radiator bracket. Attach the bottom of the box to the protruding screw and secure with washer DO NOT FILL THIS HOLE!
(233) and nut (220). Attach a jumper strap (428) between MN7 and the lower brackets and
another jumper strap between the upper and lower brackets as shown. Next, assemble and
position the mast mount rings (110). Be sure that the locking screws in the mast mount ring go
through the pre-drilled holes in the R7 base (figure 4). The counterpoise rods will be attached
later (step 5).
116 | 240116 SILICONE
PACKET
220 | 010220 HEX
MACHINE 233 | 010233 LOCK #0
290326 | IF ) | WARNING
ae aN
428 | 902428 JUMPER
MAST MT. 832 | 902832 COUNTERPOISE 49" 7
RING ae ROD (124 om)
CONNECTOR IMPEDANCE
BOOT MATCHING
ASSEMBLY

F (40 meters)
See Table 4
TABLE 1
40 Meter Setting For
Dimension F
CW CENTER PHONE
17-118"
(43.5)
28" on
(71.4 cm) (55.9 cm)
TV5 TRAP |
30 Meters
lit
Cal
““ FIGURE 5
TV4 TRAP
20 Meters
TV3 TRAP
17 Meters
p 6"
410 (15.2 cm)
TV2 TRAP
15 Meters
TV1 TRAP
10/12 Meters
412
(10 meters) A ee!
123%
49" Radials
(124.5 cm)
R7
#3 - ASSEMBLE VERTICAL
When the base assembly is completed, place worm clamp (412) over the
top of the radiator tube (AA). Insert the tube AB 6 inches (15 cm) into AA
and tighten the clamp. Continue the same procedure with tube AC. Place
worm clamp (411) over the top of AC, insert the TV1 trap, set dimension A
and tighten the worm clamp. Note that the arrows on the traps must point
up whenassembled. The X-hats willbe attachedlater during step 4. Attach
the TV2 trap with the tube AD centered between the traps and set
dimension B. The external trap capacitors should alternate from one side
of the antenna to the other as you assemble the antenna. Assemble traps
TV3, TV4 and TV5 with tubes, worm clamps and dimensions shown on
figure 5. Insert the tube AG 3 inches (7.6 cm) into the top of the TV5 trap
and tighten the clamp (409). Insert tube AH and set dimension F using the
dimensions shown in table 1. Tighten clamp (407). Place a cap (77) on the
top of tube AH.
kere Ee ee ee
050077 PLASTIC 3/8"
CAP (.95 cm)
030407 WORM 7/32"
CLAMP (.5.cm)
030409 WORM 7/8" |
CLAMP (2.2 cm)
030410 WORM a
CLAMP (2.5 cm)
411 | 030411 © WORM 4-1/4"
CLAMP (3.2 cm)
412 | 030412 WORM 1-1/2" 2
CLAMP (3.8 cm)
AA BASE 48" i
ewe 1-1/4" x 48" |
(3.2 X 121.9 cm)
pag ia 1-1/8" x 48" |
(2.9 x 121.9 cm)
1-1/8" x 9"
(2.9 X 22.9 cm)
AXA"
(2.5 x 35.6 cm)
AG 1/2" x 24" |
(1.3 x 61 cm)
3/8" x 24" 1
‘ (.9x 61 cm)
34-5/8" 1
(88 cm)
15"
(38.1 cm)
15-3/4"
(40 cm)
23 1
(53.3 cm)
22-1/4" |
(56.5 cm)

#4 - ASSEMBLE X-HATS
Assemble and attach the X-hats to the bottom of the TV1 and the top of the
TV5 traps (using the pre-drilled holes) as shown in figure 6.
14
HEX
NUT
010231 MACHINE 8-32x1-3/4" 4
XHR X-HAT 36" 4
ROD (91.4 cm)
#5 - ATTACH COUNTERPOISE RODS
Insert four of the 49 inch (124 cm) counterpoise rods into the slots on the end of the lower bracket assembly on the base insulator. Adjust the brackets
so that the rods are equally spaced about the matching network. Firmly tighten the machine screws and nuts while observing the location of the brackets
on the base insulator (figure 2). Insert the remaining three counterpoise rods into the ends of the upper bracket assembly. Tighten the machine screws.
Attach the warning labels (326) to the ends of the counterpoise rods as shown on figure 3. /T/IS VERY IMPORTANT TO USE THE WARNING LABELS
BECAUSE DEADLY VOLTAGES CAN BE PRESENT ON THESE RODS.
#6 - FEEDLINE
We have provided a weatherproof boot for the PL-259 connector on your feedline. Follow figure 3 to install it. Insert the antenna end of your coax
through the small end of your connector beot. Many cables are very tight which results in an excellent weather seal. Attach a PL-259 to the end of
your coax. Spread the silicone on the threads of the antenna connector. SILICONE SHOULD NOT BE SPREAD ON THE CENTER PIN! Apply the
remaining silicone to the outside of the connector. Attach the connector to the matching network and slip the boot over the connector until it touches
the bracket. Return to the adjustment section on page 1.

R7
-
SPECIFICATIONS
Frequency Bands (Meters) 10, 12, 15, 17, 20, 30, 40
Gain, dBi 3
Electrical Wavelength ;
Each band Half-wave
VSWR 1.2:1 Typical
2:1 Bandwidth 10m (2.0 MHz), 12m (100 KHz)
15m (450 KHz), 17m (100 KHz), 20m (150 KHz)
30m (50 KHz), 40m (75 KHz)
Power Rating, Watts PEP 1800
Radiation Angle Typical 16°
Frequency Selection Automatic
Horizontal Radiation Pattern, Degrees 360°
Height, ft. (m) 22.5 (6.9)
Mast Size Range, in. (cm) 1.5-1.75 (3.8-4.4)
Wind Load, ft.? (m?) 225 (et)
Weight, Ib. (kg) 12.3 (5.6)
49 in. (124 cm) Counterpoise Radials 7
TYPICAL R7 VSWR DATA
SWR 10 Meters SWR 12 Meters 5 de 17 Meters
1.8 1.8 5
1.6 1.6
1.4 1.4
1.2 1.2
28.0 28.4 28.8 29.2 29.6 24.8 24.85 24.9 24.95 25.0 21.0 21.1 919 21.3 21.4 18.05 18.075 18.10 18.125 18.15
Frequency MHz Frequency MHz Frequency MHz Frequency MHz
ce 20 Meters SWR 30 Meters he 40 —
d 1.8 :
1.4 1.4 1.4
ie ie ARR
14.1 14.15 14.2 14.25 14.3 10.11 10.12 10.13 10.14 7.0 7.05 Tat 7.15 a -
Frequency MHz Frequency MHz Frequency MHz
Cushcraft Corporation, P.O. Box 4680, Manchester, New Hampshire 03108, 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 judgement of Cushcraft, any such antenna is defective,
then Cushcraft Corporation will, at its option, repair or replace the antenna at its expense within thirty days of the date the antenna is returned (at
purchasers expense) to Cushcraft or one of its authorized representatives. This warranty is in lieu of all other expressed warranties, any 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 and exclusion 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.
WHERE PERFORMANCE IS A TRADITION
48 PERIMETER ROAD, MANCHESTER, NH, 03108 USA
TELEPHONE: [phone] + FAX: [phone] * TELEX: 4949472