SteppIR DB18 Yagi User manual

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EA3PW
DB18 Yagi
Assembly Manual
REV 10.2
02/25/2014
2112 116th Ave NE #1-5, Bellevue, WA 98004 Tel: [phone] email: [e-mail]
This assembly manual is intended to be
printed in full COLOR. If the manual is
printed in black and white, many im-
portant details could be lost.

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Specifications DB18 Yagi
Boom length 19 ft / 5.79 m
Boom outside diameter 1.75 in—2 in / 4.45—5.08 cm
Longest element 39 ft / 11.9 m
Turning radius 21.58 ft / 6.57 m
Weight 96 lb / 43.5 kg
Wind load 10.1 sq ft / 0.93 sq m
Wind rating 100 mph
Adjustable elements 3
Power Rating 3000 watts continuous
Feed points 3
Frequency coverage 6.8 MHz—54 MHz
Control cable 16 conductor shielded, 22AWG
Frequency Gain, dBi Front to rear, dB
40M 6.2 20
30M 5.4 NA
20M 7.4 25
17M 8.3 25
15M 8.5 20
12M 8.8 15
10M 9.0 11
6M 6.2 4
6M w/passive opt. 10.1 30
DB18 Yagi Specifications
DB18 Yagi w / 6m passive option
PREAMBLE

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DB18 TABLE OF CONTENTS (page 1 of 4) Page(s)
PREAMBLE 2-19
Antenna specifications 2
OK, NOW WHAT?? Advice from Jim Streible K4DLI 7-8
Parts checklist 9-10
Assembly kits—bill of materials 11-16
Assembly notes (Read before you start assembly 17
Antenna configuration guide 18
A word about stainless steel and potential for galling 19
CHAPTER ONE—BOOM ASSEMBLY 20-23
Section 1.0:
Boom layout 20
Boom bolt detail 21
Section 1.1:
Connecting the EZ-Eyebolt to the boom 22-23
CHAPTER TWO—MOUNTING THE BOOM TO THE MAST PLATE 24-26
Section 2.0:
Mast plate-to-boom overview 24
Preparing the mast plate for the EZ-Eyebolt 25
Section 2.1:
Attach the boom to the mast plate 26
CHAPTER THREE—MAST PLATE AND TRUSS ASSEMBLY 27-39
Section 3.0:
Element housing unit (EHU) placement 27
EHU center-to-center spacing measurements 28
Section 3.1:
EHU wiring overview 29
EHU wiring 30-31

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DB18 TABLE OF CONTENTS (page 2 of 4) Page(s)
CHAPTER THREE (continued) - MAST PLATE & TRUSS ASSEMBLY
Section 3.2:
Director EHU & return tube assembly drawing 32
Secure the mounting plate & EHU to the boom—Director element 33
Section 3.3:
Return tube mounting—Director EHU 34
Section 3.4:
Driven element EHU assembly drawing 35
Secure mounting plate & EHU to boom—Driven element 36
Section 3.5:
Reflector EHU & return tube assembly drawing 37
Secure mounting plate & EHU to boom—Reflector element 38
Section 3.6:
Return tube mounting—Reflector EHU 39
CHAPTER FOUR—COAX SWITCH HOUSING 40-43
Section 4.0:
Mounting the coax switch assembly 40
Section 4.1
Coax switch wiring 41
Section 4.2
Sealing & securing the coax switch housing 42
Attach the coax jumpers and feed line 43
CHAPTER FIVE—WIRING THE CONNECTOR JUNCTION BOX 44-53
Section 5.0:
Mount the connector junction box onto boom 41
Section 5.1:
Wiring the connector junction box 45-47
Connecting the control cable from coax switch to junction box 48

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DB18 TABLE OF CONTENTS (page 3 of 4) Page(s)
CHAPTER FIVE (continued) - WIRING THE CONNECTOR JUNCTION BOX
Section 5.2:
Connecting 16 wire control cable to 25 pin d-Sub field splice 49-50
Section 5.3:
Wiring test 51-53
CHAPTER SIX—ELEMENT SUPPORT TUBE (EHU) PREPARATION 54-59
Section 6.0
Prepare the telescoping poles for the loop elements (DIR & REF) 54-55
Section 6.1:
Attach the sweep couplers and fiberglass spreaders to the sweep tubes 56-57
Section 6.2:
Attach the fiberglass telescoping poles to the sweeps 58
Section 6.3:
Attach the foam plug housings to non-loop telescoping poles 59
CHAPTER SEVEN—ATTACH THE ELEMENTS TO THE EHU’S 60-62
Section 7.0:
Prepare the CPVC inner-guide tube & diverter cone 60
Section 7.1:
Securing the element support tube (EST) to the EHU 61-62
CHAPTER EIGHT—OPTIONAL 40/30 END ELEMENT TRUSS KIT 63-66
Section 8.0:
Installing the truss support mast 63
Section 8.1:
Attach the truss couplers 64
Section 8.2:
Routing the Dacron truss cord 65-66

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DB18 TABLE OF CONTENTS (page 4 of 4) Page(s)
CHAPTER NINE—OPTIONAL 6M PASSIVE ELEMENT KIT 67-68
Section 9.0:
Preparing the 6m passive element 67
Section 9.1:
Mounting the 6m passive element to the boom 68
CHAPTER TEN—INSTALLING THE OPTIONAL BOOM TRUSS 69—72
Section 10.0:
Installing the boom truss support 69
Section 10.1:
Phillystran truss installation 70-72
CHAPTER ELEVEN—SECURE CABLES & MOUNT ANTENNA ON TOWER 73-75
Section 11.0:
Secure the cables to the boom 73
Section 11.1:
Mount the DB18 onto the tower mast 74-75
CHAPTER TWELVE—TROUBLESHOOTING TIPS 76-78
Section 12.0:
Troubleshooting tips 76-77
SteppIR product warranty 78
Contact information 79

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OK - - - NOW WHAT?
(Sage advise from Jim Streible, K4DLI—SteppIR Technical Support Guru)
PREAMBLE
You have ordered you SteppIR Antenna and are
waiting for delivery. What do you do in the meantime?
1. Go to the SteppIR web site at www.steppir.com and download the latest manual for your antenna,
and also the Operators Manual for the controller.
2. Read the manuals from cover-to-cover ---TWICE! Don’t just read them –Study them, so you are
familiar the terminology used about the antennas and have a good idea of how the antenna is as-
sembled and where the various parts go.
3. As you go through the manuals make notes of any instructions you may not clearly understand,
then call or email for clarifications. It is better to have it all sorted out before you start assembly.
We don’t mind answering your questions beforehand.
4. Now, wait for notification your antenna is being shipped.
Your antenna has arrived!
What is the first thing to do?
1. If the antennas is to arrive on Wednesday----DO NOT plan an antenna party for Saturday!
2. Even if you plan to install the antenna weeks later, the first thing to do is to unpack the antenna
and do a complete inspection. Make sure nothing is missing or has been damaged in shipment.
3. Do a complete inventory of every part, nut and bolt. Yes it takes time, but it also allows you to
notify SteppIR if anything is missing and allow time to get it to you before you start assembly of
the antenna. There is nothing more frustrating than realizing that something is missing, just
hours before you want to install the antenna.
4. Go back to the SteppIR website and download the latest manual. SteppIR constantly is improv-
ing and adding to the manual, so even though your paper instruction manual is going to have all
the data you need, it makes sense to check for the latest updates online. This is especially true
If you purchased the antenna and a period of time has passed between arrival and install dates.
5. Take the controller and power supply out of their wrappings and connect them. The controller
does not have to be connected to the antenna in order to familiarize yourself with it. In fact, it is
best to get familiar with the controller when it is not connected to the antenna. Turn on the con-
troller and read through the Operators Manual again while operating the controller in all it
modes. Go through the menus so you know what each does and how to navigate through the
various menus and functions.

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OK - - - NOW WHAT? (continued)
(Sage advise from Jim Streible, K4DLI—SteppIR Technical Support Guru)
PREAMBLE
Your Antenna Has Arrived!
What is the first thing to do?
(continued)
5. When you have finished working with the controller be sure the display indicates “Elements
Home” and the controller has been turned OFF. When the controller is connected to the anten-
na and the controller is turned back on the next time, it will immediately tune to whatever po-
sition the controller was left in last time you were using it, so you want to be sure that position
is HOME.
6. Once the antenna is completely assembled and ready to mount on the antenna tower, use an
antenna analyzer, if you have one, to test resonance of the antenna.. If you don’t have an an-
alyzer, try to borrow one. It will save you a lot of time and worry. Check the antenna on each
band for some sign of resonance within the frequency range. Leave the antenna on the default
frequency and tune the analyzer to see where the dip occurs. It will be somewhere below the
lower band edge on each band with the antenna 3 or 4 feet above the ground on horsesAlso,
don’t expect to see a 1:1 SWR here, just look for a good indication of resonance.
Once it has been determined this part of the antenna is working correctly do the following: Se-
lect the lowest band and establish the dip condition by tuning the analyzer. Do not touch the
analyzer again. Retract the elements and then reselect the same band. The antenna should
come back the very near the same setting. Do this 2 or 3 times on each band. Also, try going
from the band being tested to any other band and back again and observe that the antenna
comes back to the same resonant point. Now you know the antenna is tuning correctly from
band to band and is consistent.
7. When you are ready to use the antenna, be sure to “enable” the DB18E in the controller menu,
or your antenna will not work properly on 40m and 30m. If you purchased the 6m option, be
sure to enable that as well. When done enabling, save and then turn the controller off, and
back on again.
8. Enjoy the antenna!
73
Jim Streible—K4DLI

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DB18 PARTS CHECKLIST
QTY Part # Description
1 70-3401-01 20m Driven element EHU, no relay (no lid - mounting plates acts as lid)
2 70-3406-01 DB18 40m Driven w/ normal passive relay (no lid, mounting plate acts as lid)
1 SDA100 Electronic controller
Options for SDA100:
1 01321 Transceiver interface
1 01324 Remote driver board
1 01323 Advanced lightning protection (ALP)
1 01322 Tuning relay
1 Power supply 24v___ (PN 09001) 33v___ (PN 09002)
EHU Control cable wire pack consisting of:
1 Length 10ft 6 inch four conductor cable
1 Length 20 ft 6 inch piece of six conductor cable (for EHU's with relays)
1 Coax seal (used to seal the control cable in the wire trough of EHU)
10 10-1013-02 18 ft telescoping fiberglass pole
1 71-0008 DB18 Instruction manual
1 71-0010 SDA 100 Instruction manual
1 09-0007 Blue silicone wrap (40/30 pole tip prep)
1 09-1025 11/16" Conical grinding stone (40/30 pole tip prep)
2 70-1007-01 Foam plug assembly (20m pole tips)
10 60-1006-22 Quick disconnect boot 1.5" x 1.25" (connect poles to EHU)
30 10-1059-01 Polyolefin heat shrink (waterproof telescoping pole joints)
1 20-6208-01 25 pin dSub connector (only used if no dsub splice purchased)
1 20-6209-01 Backshell for 25 pin dSub connector
4 10-1156-01 Plastic sweeps for 40/30 loop elements
1 10-1610-23 11.5" x 11.5" Mast plate
2 10-1608-01 Return plate for 40/30 loop
4 10-1503-21 Fiberglass sweep supports, black (connects between each sweep coupler)
2 10-1015-11 Return EST, 12" with reinforcing rings on each end
3 70-2030-01 EHU aluminum mounting plate with foam aligning gasket
1 03322 16 conductor control cable _______________ ft
1 70-3001-01 Aluminum coax switch box, with lid (lid has SO239 connectors mounted)
1 70-2037 Connector junction box
It is important that you do an inventory of the items that were shipped to you. Nothing is worse than
discovering a day before a planned installation that there are missing parts! We do our very best to en-
sure that you receive everything needed for construction of your antenna, but better to be safe than
sorry—inventory your parts well in advance of your installation. The items in blue represent options
available for the DB18 Yagi—you will need to check these items off only if you purchased them.
PREAMBLE

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ASSEMBLY KITS
(a bill of materials for each kit is shown on the next page)
QTY Part # Description
2 72-0030-61 40/30 loop hardware kit
1 72-0035-02 Boom assembly kit
1 72-0036-02 Director element hardware kit
1 72-0037-02 Reflector element hardware kit
1 72-0038-01 Driven element hardware kit
1 72-0040-01 Mast plate hardware kit
1 72-0042-11 Coax antenna switch hardware kit
1 72-0042-01 Coax antenna switch cable kit
1 72-0041-01 Glue, tape and anti-seize kit (use anti-seize on ALL stainless fasteners!)
ANTENNA OPTIONS
6m Passive Element OPTION
1 70-1001-91 6m Passive element
1 72-1001-71 Hardware kit for 6m option
Voltage suppressor (lighting arrestor) OPTION
1 20-8052-51 16 pin voltage suppressor
40/30 Loop Element Truss Kit OPTION
2 72-0018-31 Loop element truss kit
2 10-1054-02 40/30 truss support arm
Boom Truss OPTION
1 72-0043-01 Boom truss kit
1 10-1618-11 Boom support mast
DB18 PARTS CHECKLIST (continued)
PREAMBLE

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ASSEMBLY KITS- BILL OF MATERIALS
QTY PART NUMBER DESCRIPTION
4 09-0013 3M Grip tape
28 60-0014 6-32 Nylock nut
28 60-0156 6-32 x 2” SS Pan head screw
8 halves 10-1155-01 Glass filled plastic sweep couplers
40/30 Loop Hardware Kit
72-0030-61
QTY PART NUMBER DESCRIPTION

9 60-0029 ¼-20 X 3” Stainless steel hex bolt
30 60-0041 1/4” Stainless steel washer
1 60-0037-21 5/16” x 4” Eyebolt S/S
2 60-0046 5/16” Nylock nut
9 60-0030 1/4” - 20 Nylock nut
1 60-0103 3” x 5/16” Hex head bolt
3 60-0033 5/16” Flat washer
Boom Assembly Kit
72-0035-02
PREAMBLE

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Director Element Hardware Kit
72-0036-02
QTY PART NUMBER DESCRIPTION
10 60-0017 10-32 X 3/4” Stainless steel machine screw
10 60-0018 # 10 SS washer
10 60-0019 10-32 Nylock nut
12 60-0046 5/16” Nylock nut
12 60-0065 5/16” X 3 1/2” Stainless steel hex head bolt
12 10-1601-02 1-¾” Aluminum saddle half
Reflector Element Hardware Kit
72-0037-02
QTY PART NUMBER DESCRIPTION
10 60-0017 10-32 X 3/4” Stainless steel machine screw
10 60-0018 # 10 SS washer
10 60-0019 10-32 Nylock nut
4 60-0046 5/16” Nylock nuts
4 60-0065 5/16” X 3-1/2” Stainless steel hex head bolt
4 10-1601-22 2” Aluminum saddle half
Driven Element Hardware Kit
72-0038-01
QTY PART NUMBER DESCRIPTION
10 60-0017 10-32 X 3/4” Stainless steel machine screw
10 60-0018 # 10 SS washer
10 60-0019 10-32 Nylock nut
12 60-0046 5/16” Nylock nut
12 60-0065 5/16” X 3-1/2” Stainless steel Hex head bolt
12 10-1601-03 1-¾” Aluminum saddle half
ASSEMBLY KITS- BILL OF MATERIALS (continued)
PREAMBLE

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QTY PART NUMBER DESCRIPTION
12 10-1601-22 2” Aluminum saddle half
14 60-0046 5/16” Nylock nut
14 60-0114 5/16 X 3-3/4 ” Stainless steel hex head bolt
1 60-0085 3/8” X 4” Stainless steel all-thread hex head bolt
1 60-0049 3/8” Stainless steel nut
2 60-0050 3/8” Nylock nut
4 60-0034 3/8” Stainless steel washer
4 60-0113 10-32 X 5/8” Stainless steel machine screw
50 60-0112 10-32 SS set screw
(use one set screw per pair of saddles)
Mast Plate Hardware Kit
72-0040-01
QTY PART NUMBER DESCRIPTION
1 72-0009-03 Glue kit
2 09-0001 66’ PVC electrical tape
2 10-1028-01 Anti-Seize
4 10-1509-02 Diverter cone
Glue, Tape & Anti-Seize Kit
72-0041-01
ASSEMBLY KITS- BILL OF MATERIALS (continued)
PREAMBLE

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QTY PART NUMBER DESCRIPTION
1 21-6301-96 11’ 6” Coax jumper (Reflector element)
1 21-6301-80 8’ Coax Jumper for (Director element)
1 21-6301-30 4 ft Coax Jumper (Driven element)
1 03122 3 ft length 4 conductor control
Coax Antenna Switch Cable Kit*
72-0042-11
QTY PART NUMBER DESCRIPTION
1 70-3001-01 Antenna switch w/ gasket, hardware and relay board
1 10-1619-01 Coax switch bracket
2 10-1601-22 2” Aluminum saddle half
2 60-0065 5/16” X 3 1/2” Stainless steel hex head bolt
2 60-0046 5/16” Nylock nut
3 60-0113 10-32 X 5/8” Stainless steel machine screw
3 60-0019 10-32 Nylock nut
Coax Antenna Switch Hardware Kit
72-0042-01
ASSEMBLY KITS- BILL OF MATERIALS (continued)
*This kit is not in a bag. The kit consists of the jumpers and the control cable, wrapped together for ship-
ping purposes.
PREAMBLE

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ASSEMBLY KITS- BILL OF MATERIALS (OPTIONAL ITEMS)
6M PASSIVE ELEMENT KIT
QTY PART NUMBER DESCRIPTION
1 10-1019-31 6m Element mounting plate
2 60-0001 1” U-bolt
4 60-0030 1/4” Nylock Nut
2 60-6000-60 1/2” SS Hose Clamp
2 10-1601-03 2” Aluminum saddle half
2 60-0075 5/16” X 3-1/2” Hex head bolt
2 60-0046 5/16” Nylock nut
QTY PART NUMBER DESCRIPTION
2 10-1601-03 1 3/4” Aluminum saddle half
8 10-1510-01 Element truss clamp
2 60-0083 4” Stainless turnbuckle
2 60-0158 1/8” Thimble
4 60-0157 1/8” Wire clip
1 60-0110 1/4” x 1-1/4” Hex Bolt
1 60-0030 1/4” Nylock Nut
2 60-0065 5/16” x 3 1/2” Hex head bolt
2 60-0046 5/16” Nylock nut
2 60-0033 5/16” Flat washer
1 21-7001-01 75' 1/8” Dacron Rope (uncut)
16 60-0014 6-32 Nylock Nut
16 60-0014-01 6-32 x 7/8” Pan head machine screw
1 10-1028-01 Anti-seize packet
1 09-0001 Electrical Tape
1 60-0112 Set Screw
END TRUSS KIT
72-0018-01
(Quantities below are for one complete element truss kit—there are two truss kits included for a DB18 Yagi.)
PREAMBLE

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Page 16
ASSEMBLY KITS- BILL OF MATERIALS (OPTIONAL ITEMS)
QTY PART NUMBER DESCRIPTION
16 60-0045 3/16” Wire Clip
4 60-0048 3/16” Wire thimble
4 60-0044 Phillystran cap
2 10-1607-01 Truss attachment plate
4 10-1601-02 1-3/4” Aluminum saddle half
4 10-1613-01 1” Aluminum Spacer
4 60-0115 5/16” x 4-1/2“ Hex head Bolt
5 60-0046 5/16” Nylock Nut
2 60-0083 4” Stainless steel turnbuckle
1 60-0093 5/16” x 2-3/4” Hex head bolt
2 60-0033 5/16 Flat washer
12 FT 60-0035-00 Phillystran 1200i
1 10-1618-11 1-3/4” x 30” Boom Truss Mast
BOOM TRUSS KIT
72-0043-01
PREAMBLE

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Page 17
ASSEMBLY NOTES
PREAMBLE
Before beginning assembly of this antenna, please read the manual in it’s entirety to familiar-
ize yourself with the task at hand. Doing so will eliminate potential confusion.
Be sure to do an inventory of your parts as soon as possible after receipt of the antenna, and
well before your intended installation date - this way we can get you the parts required before
it’s too late.
Be sure to check the insides of the aluminum tubing and the telescoping poles when unpack-
ing your boxes. In certain situations we put items inside these pieces to reduce the amount of
boxes used for shipping, which in turn reduces your shipping costs.
A large, cleared flat area is recommended for assembly of an antenna of this size and com-
plexity. Typically, an area 40 ft x 25 ft would be ideal. We recommend using sawhorses or
sturdy tables when installing the boom. By having the boom elevated, it is easier to ensure
that the elements are level. Rubber or nitrile gloves are recommended when applying the anti
-seize to the stainless steel fasteners or the aluminum boom sections.
Be sure to refer to the DB18 configuration drawing on the following page so that you can fully
understand how the antenna operates. In addition, the configuration drawing identifies EHU
placement, which is important as you progress in your installation of the antenna.
Use of a level for adjusting the Element Housing Units (EHU’s) is highly recommended. This is
a surprisingly accurate and consistent method. When all the EHU’s are level, secure the boom
to the sawhorses so that it cannot shift—this will help considerably when you are leveling the
mast plate.
Be sure to use the anti-seize compound supplied to prevent the galling of the stainless steel
fasteners. If you do not use the anti-seize, count on issues with the stainless steel hardware
galling. Heat is one of the primary culprits with galling, so if you use a ratchet, steady speed
as you tighten will help minimize galling. We have found that when the anti-seize is applied to
the bolt portion of the hardware, it will eliminate any galling issues.
NEVER ATTEMPT TO WIRE OR CHANGE WIRING ON THE ANTENNA WHEN THE ELECTRONIC
CONTROLLER IS CONNECTED TO THE CONTROL CABLE, EVEN IF IT IS TURNED OFF. This is
the number one cause of installation failures for our products. Even with power off, damage
can occur. When the power is “off” on your controller, there is still a very small amount of
power feeding to the stepper motors, to effectively “lock” them in place. This leads to less
need for calibration of the antenna.

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Page 18
REVERSE DIRECTION (180 deg)
40/30m Driven
20m-6m Director
ANTENNA CONFIGURATION GUIDE
FORWARD DIRECTION (Normal)
The DB18 Yagi antenna uses loop elements for 30m and 40M performance. The loop elements used for 40m
and 30m are 40% shorter than a full size element, with very little sacrifice in performance (-0.3dB).
The DB18 uses an integral coax switch to select which one of the three elements are driven to give equal
performance in forward and reverse directions. Each of the loop elements has a relay inside of the EHU.
The control of the antenna and coax switch is integrated into the SDA100 controller for effortless tuning.
The DB18 is a 2 element Yagi on 40m. It has two elements on 30m as well, but because of the wide spac-
ing between elements, the antenna performs more like a high gain dipole on this band. The DB18 has 3 ele-
ments on 20m-6m. An optional 6m passive element kit is available.
The drawing below shows the element configuration of the DB18, so you can better understand what is
happening when you push the buttons on the SDA100 controller!
40m, 20-6m Reflector
30m Driven
RELAY
INSIDE
EHU
RELAY
INSIDE
EHU
NO RELAY 20m-6m Driven
20m-6m Driven
40m, 20m-6m Reflector
40m Driven
20m-6m Director
Optional 6m Passive Element
This element not used when on 40m & 30m This element not used when on 40m & 30m
PREAMBLE

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Page 19
From time to time, we get complaints from customers regarding galling of stainless steel fasteners.
Here is an excerpt from the Industrial Fastener Institute's Standards Book:
Thread galling seems to be the most prevalent with fasteners made of stainless steel, aluminum,
titanium and other alloys which self-generate an oxide surface film for corrosion protection. During
fastener tightening, as pressure builds between the contacting and sliding thread surfaces, protec-
tive oxides are broken, possibly wiped off and interface metal high points shear or lock together.
This cumulative clogging-shearing-locking action causes increasing adhesion. In the extreme, galling
leads to seizing - the actual freezing together of the threads. If tightening is continued, the fastener
can be twisted off or its threads ripped out.
During minor galling, the fastener can still be removed, but in severe cases of galling, a strong bond
between the bolt and nut can prevent removal of fasteners. Unfortunately, little is known on how to
control it, but here are two ways to minimize this effect:
Decreasing installation RPM speed will cause less friction and decrease heat generation. Lubrication
used prior to assembly can dramatically reduce or eliminate galling. Recommended lubricants should
contain higher amounts of molybdenum disulfide, such as graphite which is very commonly used as
a solid lubricant or special anti-galling lubricants sold by chemical companies.
We provide an anti-seize compound stick called “Thread Magic” (shown in picture below) with all of
our antennas and strongly encourage you to use it to reduce the aggravation of galling. The
Thread Magic stick is fantastic—you can get plenty of anti-seize on the fastener without getting it on
your hands!
Contrary to popular belief, galling of stainless steel is not a symptom of a "cheap" fastener - it is
prevalent in all types of stainless steel, aluminum and titanium fasteners. You can be assured that
the stainless steel fasteners we provide with our products are manufactured of very high quality.
A WORD ABOUT STAINLESS STEEL GALLING
PREAMBLE

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Page 20
CHAPTER ONE
SECTION 1.0 BOOM ASSEMBLY
Our boom pieces are all drilled on a very precise drill press. This ensures that all the bolts are snug when
assembled. It is always better to be too tight than too loose. Always apply an anti-seize lubricant to
stainless steel bolts that are using stainless steel nuts. This will prevent the two from galling together.
Galling of stainless steel is common and has nothing to do with the quality of the material. Refer to the
galling information in the Preamble section of this manual.
Each bolt has a specific length for the particular tubing it is holding together. It is important that the
shank of the bolt is engaged in the tubing, since that is the strongest portion of the bolt. Use 5 washers
per bolt to secure the bolt as shown in figure 1.02 on the following page.
Apply a thin film of a lubricant such as Anti-seize or Noalox to the male engagement area of the alumi-
num boom sections. Failure to do so may cause the tubes to seize inside each other. Match the boom
pieces as shown below and slide each boom piece together until the pre-drilled holes align.
Secure the correct bolts and washers onto the boom as shown in figure 1.01. Repeat this for each sec-
tion until the boom is completely assembled. Note that boom piece 10-1202-52 has two 1/4” drill holes on
the end that connects to the 1-3/4” boom section, and 5/16” drill holes on the end that the EZ eyebolt at-
taches to. The rest of the bolts are 1/4”. Figure 1.10 in Chapter One, Section 1.1 shows a detailed draw-
ing of the EZ-Eyebolt.
Secure the 5/16” eyebolt as shown in figure 1.03 and figure 1.04. This eyebolt is part of our EZ-Eye sys-
tem, which helps to level the boom and also assists in keeping the boom from shifting during high winds.
This will be covered in more detail later in this manual.
BOOM LAYOUT
1-3/4” x 48” Boom Section
10-1202-41
2” x 72” Boom Section
10-1202-52
2” x 72” Boom Section
10-1202-11
1-3/4” x 48” Boom Section
10-1202-41
QTY 2: 60-0029
1/4” x 3” Hex bolt
QTY 10: 60-0041
1/4” Flat washer
QTY 2: 60-0030
1/4” Nylock nut
QTY 1: 60-0103
5/16” x 3” Hex bolt
QTY 2: 60-0033
5/16” Flat washer
QTY 1: 60-0046
5/16” Nylock nut
QTY 2: 60-0029
1/4”x3” Hex bolt
QTY 10: 60-0041
1/4” Flat washer
QTY 2: 60-0030
1/4” Nylock nut
QTY 2: 60-0029
1/4” x 3” Hex bolt
and
QTY 10: 60-0041
1/4” Flat washer
QTY 2: 60-0030
1/4” Nylock nut
QTY 1: 60-0037-21
5/16” x 4” Eyebolt
QTY 1: 60-0046
5/16” Nylock nut
QTY 1: 60-0033
5/16” Flat washer
(place between eye-
bolt and aluminum
tube)
Be sure the 10-1203-01
boom sleeve is in place
FIG. 1.01