CUSHCRAFT A50-5S Instruction Manual

ASSEMBLY AND INSTALLATION
5 ELEMENT
6 METER BEAM
A50-5S
C O R P O R A T I O N
951365 (11/94)

A50-5S
YourCushcraft6meterbeamisdesignedandmanufacturedtogivetopperformanceandtroublefreeservice. Theantennawillperformasspecified
if the instructions and suggestions are followed and care is used in assembly and installation. When checking the components received in your
antenna package use the parts lists in each section. It is easiest to identify the various dimensions of tubing by separating them into groups of the
same diameter and length. 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. There is a master parts list on page 2.
LOCATION
Locationoftheantennaisveryimportant. Surroundingobjectssuchastrees,powerlines,otherantennas,etc.willseriouslyreduceefficiency. To
minimize the effects of surrounding objects, mount the antenna as high and in the clear as possible. If metal guy wires are used, they should be
brokenwithstraininsulators. YOUMUSTINSURETHATNEITHERPEOPLEORPETSCANCOMEINCONTACTWITHYOURANTENNAWHILE
IT IS IN OPERATION. 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 IS A WARNING STICKER
WHICH MUST BE ATTACHED TO THE BOOM AS SHOWN IN FIGURE E.
Plan your installation carefully. If you use volunteer helpers be sure that they are qualified to assist you. Make certain that everyone involved
understands that you are in charge and that they must follow your instructions. If you have any doubts at all employ a professional antenna
installation company to install your antenna.
MOUNTING
The mast mount bracket will accommodate up to a 2" OD (5.1 cm) mast. A 1-1/2" OD (3.8 cm) or larger heavy wall tubing mast should be used.
A good heavy duty antenna rotator will provide the best service and longest life. Often it is desirable to mount several antennas on one mast. To
keep possible interaction to a minimum, place your antennas as far apart as you can.
SYSTEM GROUNDING
Directgrounding oftheantenna, mastandtower isveryimportant. Thisservesasprotectionfromlightningstrikesandstatic buildup,andfrom high
voltage which is present in the radio equipment connected to the antenna. A good electrical connection should be made to one or more ground
rods(orother extensivegroundsystem) directly atthebase of thetoweror mast,usingatleast #10AWG groundwireandnon-corrosive hardware.
For details and safety standards, consult the National Electrical Code. You should also use a coaxial lightning arrester. Cushcraft offers several
different models, such as LAC-1, LAC-2 and the LAC-4 series.
ASSEMBLY
Assembleyourantennabyfollowingthedirectionsandillustrationsinsteps1through5. VerticalpolarizationisnormallyusedforFM. Othermodes
use horizontal polarization. After the antenna is completely assembled, verify dimensions and element spacings for accuracy. Then, return to the
section below for final tuning.
TUNING PROCEDURE
IfyouwishtochecktheVSWRbeforeinstallation,pleaseobservethefollowingprocedures. Temporarilymounttheantennawiththeboomvertical,
reflectoratleastonefoot(30cm)offthe groundonanon-metallicsupport(woodenbox), topreventdetuningtheantenna. Guy thetopoftheboom.
Do not use line with wire in it (some clotheslines have a wire core). Keep other antennas, metal objects and guy lines clear of the antenna under
test. Do not attempt to tune the Yagi near the ground with the boom parallel to the ground since ground effects will nullify any adjustment and
degraded performance will result.
Runthecoaxcablefromyourtransmittertotheareainwhichtheantennaisgoingtobetested. Thelengthofthiscableoryourfeedlineisnotcritical.
Connect a good quality VSWR bridge to the end of this cable. Connect a short length of cable [10 ft (305 cm) or less] from the VSWR bridge to
theantenna. Set the transmitter to your centeroperating frequency. When you read VSWR, besure you move far enough awayfrom the antenna
so that your body does not effect the reading.
Measure the VSWR. If it is high, move the Reddi-Match clamp (69) by 1/4" (.6 cm) in one direction and check the VSWR. If the VSWR improved,
then continue moving the Reddi-Match clamp in the same direction. If the VSWR deteriorated then move the Reddi-Match clamp in the opposite
direction. Repeat this procedure until no further improvement can be made. You have matched your antenna to 50 Ohms. Then tighten all
connections. Tape the feedline to the boom and mast.
WARNING
THIS ANTENNA IS AN ELECTRICAL CONDUCTOR. CONTACT WITH POWER LINES CAN RESULT IN DEATH, OR SERIOUS
INJURY. DONOTINSTALL THIS ANTENNA WHERE THERE IS ANY POSSIBILITY OF CONTACTWITHORHIGH 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 OR IN 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.
1

A50-5S
KEY P/N DESCRIPTION QUANTITY
MASTER PARTS LIST
13 050013 PLASTIC 1-1/4" 2
CAP (3.8 cm)
412 030412 TELESCOPE 1-3/8" 2
CLAMP (3.5 cm)
AA ALUM 1-3/8" X 50" 1
TUBE (3.5 x 127 cm)
BB ALUM 1-1/4" x 50" 2
TUBING (3.17 x 127 cm)
KEY P/N DISPLAY DESC SIZE QTY KEY P/N DISPLAY DESC SIZE QTY
Place a mark 3 inches (7.6 cm) in from one end of the BB tubes. Next, place clamp (412) over the ends of the AA tube. Slide the BB tubes
into AA up to the 3" mark, check overall dimension and if correct, tighten clamps. Slide on end caps (13).
#1 - BOOM ASSEMBLY
9 010009 8-32 x 5/8" (1.59 cm) stainless steel machine screw 2
11 010011 8-32 stainless steel hex nut 3
13 050013 1-1/4" (3.17 cm) plastic cap 2
27 050027 5/8" (1.59 cm) plastic caps 10
32 190032 1-1/2" (3.8 cm) heavy duty U-bolt brackets 5
33 190033 1-1/2" (3.8 cm) U-bolt backing plate 4
69 200069 Formed aluminum tuning strap 1
70 190070 4" x 6" (10.2 x 15.2 cm) formed mast plate 1
84 010084 1/4" (.63 cm) stainless steel lock washer 10
85 010085 1/4" (.63 cm) stainless steel hex nut 10
115 050115 Connector boot 1
116 240116 Silicone package 1
118 010118 5/16" (.8 cm) stainless steel hex nut 8
119 010119 5/16" (.8 cm) stainless steel lock washers 8
326 290326 Danger label 1
402 010402 1-1/2" (3.8 cm) stainless steel U-bolt 5
403 010403 1-5/8" (4.13 cm) stainless steel U-bolt 2
404 010404 2" x 3" (5.1 x 7.6 cm) stainless steel U-bolt 2
409 030409 3/4" (1.9 cm) stainless steel worm clamps 10
412 030412 1-3/8" (3.49 cm) stainless steel worm clamps 2
941 011941 #8 stainless steel lock washer 3
AA 1-3/8" x 50" (3.49 x 127 cm) aluminum tubing, slotted both ends 1
BB 1-1/4" x 50" (3.17 x 127 cm) aluminum tubing 2
EA 3/4" x 48" (1.9 x 121.9 cm) aluminum tubing slotted both ends 5
EB 5/8" x 40-1/2" (1.6 x 102.9 cm) aluminum tubing 2
EC 5/8" x 35-3/4" (1.6 x 90.8 cm) aluminum tubing 2
ED 5/8" x 33" (1.6 x 83.8 cm) aluminum tubing 2
EE 5/8" x 32-1/2" (1.6 x 82.5 cm) aluminum tubing 2
EF 5/8" x 32" (1.6 x 81.3 cm) aluminum tubing 2
CB Connector Bracket 1
RM Reddi Match tube Assembly 1
2
FIGURE A
13
412
AA
BB
13
412
144"
(3.66 m)
3" Insert
(7.62 cm)
BB
3" Insert
(7.62 cm)

#2 - ELEMENT ASSEMBLY & MOUNTING
The elements are made up of one pre-drilled and slotted 3/4" (1.9 cm) O.D. center tube and two pre-cut 5/8" (1.59 cm) O.D. end tubes. Assemble
the elements using Figure B for horizontal polarization or Figure B-2 for vertical polarization. Slide the tuning strap (69) on one of the EA tubes.
This will be the driven element #2. Place telescope clamps (409) loosely on the slotted ends of all EA tubes. Note that the EC tubes must be used
with the EA tube on which you placed the tuning strap (69). Attach caps (27) to the end of each element. Mount the elements to the boom (Figure
C). Refer to figure D for mounting the dipole element with the connector bracket. Mount the connector with the threads (socket) pointing to the
mast mount. Adjust the antenna to your preferred portion of the 6 meter band using Table 1 if you've chosen horizontal polarization or Table 2 for
vertical polarization. Tighten all connections.
Horizontal Polarization
50 MHz- 51.5 MHz- 53 MHz
51.5 MHz 53 MHz 54 MHz
REF in. 35-1/8 34 32-1/8
(cm) (89.22) (86.36) (81.60)
DE in. 31-3/4 28-3/8 26-7/8
(cm) (80.64) (72.07) (68.26)
D1 in. 29-3/4 27 26-1/4
(cm) (75.56) (68.58) (66.67)
D2 in. 29-3/4 24-7/8 24-5/8
(cm) (75.56) (63.18) (62.55)
D3 in. 25-5/8 24-1/2 23-1/2
(cm) (65.09) (62.23) (59.69)
Set in. 15-5/8 16-1/2 17
(cm) (39.69) (41.91) (43.18)
Xin. 1-7/8 3 3
(cm) (4.76) (7.62) (7.62)
FIGURE C
Vertical Polarization
50 MHz- 51.5 MHz- 53 MHz
51.5 MHz 53 MHz 54 MHz
REF in. 37-1/2 35-1/2 33-1/2
(cm) (95.25) (90.17) (85.09)
DE in. 30-3/4 30-3/4 30-3/4
(cm) (78.10) (78.10) (78.10)
D1 in. 30 28 26
(cm) (76.2) (71.12) (66.04)
D2 in. 29-1/2 27-1/2 25-1/2
(cm) (74.93) (69.85) (64.77)
D3 in. 29 27 25
(cm) (73.66) (68.58) (63.5)
Set in. 15-5/8 15-5/8 18
(cm) (39.69) (39.69) (45.72)
Xin. 2 2 1-1/2
(cm) (5.08) (5.08) (3.81)
EA ALUM 3/4" x 48" 5
TUBING (1.9 x 121.9 cm)
EB ALUM 5/8" x 40-1/2" 2
TUBING (1.6 x 102.9 cm)
EC ALUM 5/8" x 35-3/4" 2
TUBING (1.6 x 90.8 cm )
ED ALUM 5/8" x 33" 2
TUBING (1.6 x 83.8 cm )
EE ALUM 5/8" x 32-1/2" 2
TUBING (1.6 x 82.5 cm)
EF ALUM 5/8" x 32" 2
TUBING (1.6 x 81.3 cm )
27 050027 PLASTIC 5/8" 10
CAP (1.59 cm)
32 190032 U-BOLT 1-1/2" 5
BRACKET (3.8 cm)
KEY P/N DISPLAY DESC SIZE QTYKEY P/N DISPLAY DESC SIZE QTY
33 190033 BACKING 1-1/2" 4
PLATE (3.8 cm)
69 200069 TUNING 1
STRAP
85 010085 HEX 1/4" 10
NUT (.63 cm)
84 010084 LOCK 1/4" 10
WASHER (.63 cm)
326 290326 DANGER 1
LABEL
402 010402 U-BOLT 1-1/2" 5
(3.8 cm)
409 030409 WORM 3/4" 10
CLAMP (1.9 cm)
Table 2
FIGURE B
Horizontal
Polarization
FIGURE B-2
(Vertical Polarization)
Table 1
EE
EE EA
48"
(121.9 cm)
31.0"
(78.7 cm)
EC EC
48"
(121.9 cm)
DE
FRONT
EA 69
27 27
409
409 ED
ED
35"
(88.9 cm)
27 27
27 27
409
69
409 409
EA
#1 - REFLECTOR
#2 - DRIVEN
ELEMENT
#4 - DIRECTOR
BB
AA
D1
D1
DE
48"
(121.9 cm) D2
D2
326
EB EB
48"
(121.9 cm)
REF
2"
(5.1 cm)
27 27
409 409
EA
BB
REF
EF
EF EA
27 27409 409
#5 - DIRECTOR
48"
(121.9 cm) D3
D3
35"
(88.9 cm)
35"
(88.9 cm)
35"
(88.9 cm)
#3 - DIRECTOR
409
EE
EE
EA
48"
(121.9 cm)
31"
(78.7 cm)
EC
EC
48"
(121.9 cm)
DE
FRONT
EA
69
27
27
409
409
ED
ED
35"
(88.9 cm)
27
27
27
27
409
409
409
409
69
#1 - REFLECTOR#2 - DRIVEN ELEMENT#4 - DIRECTOR
BB AA
D1
D1
DE
48"
(121.9 cm)
D2
D2
EB
EB
48"
(121.9 cm)
REF
2"
(5.1 cm)
27
27
409
409
EA
BB
REF
EF
EF
EA
27
27
409
409
#5 - DIRECTOR
48"
(121.9 cm)
D3
D3
35"
(88.9 cm)
35"
(88.9 cm) 35"
(88.9 cm)
#3 - DIRECTOR
EA
326
402
32
33
84
85
84
85
34
A50-5S
A50-5S

A50-5S
70 190070 MAST MT. 4" X 6" 1
PLATE (15.2 x 15.2 cm)
118 010118 HEX 5/16" 8
NUT (.8 cm)
119 010119 LOCK 5/16" 8
WASHER (.8 cm)
326 290326 DANGER 1
LABEL
403 010403 U-BOLT 1-5/8" 2
(4.13 cm)
404 010404 U-BOLT 2" x 3" 2
(5.08 x 7.62 cm )
9 010009 SS MACHINE 8-32 X 5/8" 2
SCREW (1.59 cm)
941 011941 SS LOCK #8 3
WASHER
11 010011 SS HEX 8-32 3
NUT
32 190032 U-BOLT 1-1/2" 1
BRACKET (3.8 cm)
69 200069 TUNING 1
STRAP
#3 - REDDI MATCH ASSEMBLY
MounttheReddiMatchtothedrivenelementasshowninfigureD. The
tuning strap (69) should already be on the element. Slide the Reddi
Match tube (RM) through the tuning strap (69). Connect the flattened
rod to the screw on the connector. Attach the driven element to the
boomusingU-bolt(402)withlockwasher(84)andhexnut(85)withthe
connectorfacingthedirectorelements. Slidethepolytubeovertherod
up to the flattened end. Adjust to the dimensions shown in Table 1 for
horizontal polarization and Table 2 for vertical polarization. Tighten all
connectors.
FIGURE D
#4 - BOOM TO MAST ASSEMBLY
Mount the antenna to the mast at the location shown in Figures B
and B-2. Mounting hardware is shown below (Figure E).
KEY P/N DISPLAY DESC SIZE QTYKEY P/N DISPLAY DESC SIZE QTY
85 010085 HEX 1/4" 2
NUT (.63 cm)
84 010084 LOCK 1/4" 2
WASHER (.63 cm)
402 010402 U-BOLTS 1-1/2" 1
(3.8 cm)
CB CONNECTOR 1
BRACKET
RM REDDI MATCH 19" 1
TUBE (48.3 cm)
FIGURE E
KEY P/N DISPLAY DESC SIZE QTY
5
After the Reddi-Match tube has
been attached to the driven
element, adjust the angle of the
tuning strap (69) to a point which
brings the Reddi-Match tube into
parallel with the driven element.
69
9
11
941
11 CB
EA
32
402
RM
84
85
X
SET
941
NOTE: For vertical polarization
the Reddi-Match assembly
should point skyward.
MAST
118
119
118
119
118 119
404
403
403
70
326
AA
Poly Tube
Poly tube on Reddi-Match
should be touching the
flaired rod end.

A50-5S
115 050115 CONNECTOR 1
BOOT
116 240116 SILICONE 1
PACKAGE
KEY P/N DISPLAY DESC SIZE QTY #5 - FEEDLINE ASSEMBLY
Before attaching the feedline permanently, tune the antenna as
outlined on page 1. The antenna is designed for use with 50 Ohm
coaxial cable terminated with a PL-259 connector. Any length of
feedline can be used with your A50-5S.The shortest length of cable
willhavetheleastloss. Aconnectorbootisincludedforusewithyour
new antenna. (Figure F) Slide the boot over the cable before
attachingyourPL-259. Coat onlytheoutside connector threadsand
shell with silicone grease. Do not coat the center pin or receptacle.
AfterthePL-259 is firmlyscrewedonto the antennaconnector,slide
thevinylbootovertheconnectorandagainstthemastbracket. Tape
the feedline to the boom and down the mast. It's a good idea to form
a drip loop in the coax to help protect the connector from water
damage (figure G).
FIGURE F
FIGURE G
6
LIMITED WARRANTY
CushcraftCorporation,P.O.Box4680,Manchester,NewHampshire03108, warrantstotheoriginalconsumerpurchaserforoneyearfromdateofpurchasethateachCushcraftantenna
isfree ofdefectsin materialor workmanship. If,inthe judgementof Cushcraft, anysuch antennaisdefective, thenCushcraft Corporationwill,at itsoption, repairorreplace theantenna
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.
cushcraft
SILICONE GREASE
cushcraft
COAT WITH SILICONE GREASE
(DO NOT coat the center pin or socket!)
cushcraft
Frequency
Number Elements
Forward Gain
Front to Back Ratio
SWR Typical
2:1 Bandwidth, MHz
Power
Boom Length
Longest Element
Turning Radius
Mast Size Range
Wind Surface Area
Weight
50-54 MHz
5
10.5 dBd
24 dB
1.2:1
>1
1000 Watts
12 ft. (3.7 m)
123" (312.4 cm)
7.8 ft. (2.37 m)
1.5-2.0 in (3.8-5.1 cm)
2.9 ft2. (.273 m2)
11 lb. (5.0 kg)
SPECIFICATIONS