Wire Antennas

© Brooke Clarke, N6GCE 2008 - 2010

as received	components of one bag 12 Al poles, 6 spreaders, 18 stakes

This page was started after I received a couple of the Camouflage Netting Mast Kits.  The Intent is to use the aluminum mast sectiions to support a wire antenna.  There are military mast kits, like the GRA-4 or GRA-12 that are much more expensive.  Using theseCamouflage poles may be a lower cost alternative.

There are a number of versions of the system.  Coloring comes in three flavors: Desert, Woodland and Snow.  Each of these has two sides to the netting that are slightly different for the different seasons of the year.  Also there are radar scattering Type II, III and IV as well as radar transparent screens.  The radar scattering screens are not on the surplus market but the radar transpartet type are available.

Each kit comes in it's own bag.  One of mine is marked:
1080-01-108-1173 (NSN for Woodland/Desert Support system, not just the bag)
Camouflage Screening
Support System
Woodland/Desert
97403/4M703
DAAJ00-88-C-B513
Lot # 054

Contents of the bag:
12 aluminum Poles 44.5" long (excluding the connector)
6 Spreaders
18 Stakes

Each mast section is a tube just under 4 feet in overall length.  It's made of two tubes that are swaged toghther.  The outer tube is 1 25/32" O.D. ( 1.785") and is 1 9/16" I.D. (1.5625).
The smaller tube is about 5 7/8" long and is inside the main tube for a little over 1 1/2".  It's O.D. is the same as the I.D. of the main tube and it's I.D. is 1.35".  There are two swage rings that lock these toghther.

The AB-1089/U is a triangular assembly that has three tubes that accept mast sections to be used as the legs of a tripod and a center tube that accepts the mast.  The tripod leg tubes have an I.D. of 1.365" which is also about the I.D. of the cammo netting mast small tube I.D., i.e. the cammo net mast will NOT fit the AB-1089.

Intended use is to combine one spreader assembly (one adapter assembly and three pedals) with various numbers of poles (1 to 4 typically) where the pedals support the Camouflage Screen and the stakes are used to hold down the screen.  No guys are used in the system.

Antenna Mast Spike Base, NEW, 1.5 and 1-5/8 OD GRC Ham

TM 5-1080-200-10-HR Lightweight Camouflage Screen Systems
TM 5-1080-200-13&P Lightweight Camouflage Screen Systems and Support Systems

When used to support a wire antenna the mast sections would be stacked to get (12 sections * 44.5"/section=) 534" (44.5 feet) if all 12 sections are in one mast.  Note that the poles need to support not only the weight of one end of the wire antenna they also need to support the vertical component of the guy tension and the vertical component of the antenna tension.  The latter value can be quite high if you try to pull the wire very tight to minimize wire sag.   These vertical loads are why the telescoping type masts are said to be used for "Light Weight" wire antennas only. 

Parts Needed

To use these poles for a wire antenna the following additional parts are needed:

Guy Rings - 2, 3 or 4 rings depending on overall mast height
Quick-Links - between guy rope and Guy Rings
Guy Ropes - enough for all the guys - rule of thumb the distance out from the base should be about 2/3 of the guy ring height or more.  With two or more guy rings on a mast it's common to use only one stake for each azimuth, but it would be stronger to use a separate stake for each guy rope.
pulley and way to attach it to top of upper mast section.

The guy rope shown at left is from The Mast Company is not parachute cord, but rather appears to be the same material used for guys on military mast systems.

Halyard & Pulley - to raise antenna after the mast is in place.  Note:  It's much harder to erect a mast with the weight of the antenna already attached, but can be done with light weight antennas.
Base anchor - one for each mast - needed to keep mast from punching into the ground.  An option is to put something hard below the mast.

This is a 185 foot long T2FD type dipole with 3 foot separation between the wires.  Unlike the BWD-90 which can be supported by just the ends this one requires additional support at the center.  I was thinking that means a center mast, but today realized that's not the case.  For example if pulleys are installed at each end and at the center FDMK Mounting Kit the antenna can be pulled over a support line using a second antenna line attached to one end of the antenna.  The support line may for example have one end high up in a tree.  Once the antenna has all three pulleys on the support line, it's other end can be lifted using a second pulley arrangement on one of the camouflage support masts.

This method can also be used to support the center of a dipole by running the center up one of the guy lines of a mast.  The advantages of this are:

• The dipole center can be a few feet from the metal mast instead of in contact with it. 
  
• The coax feed line can have pulley supports every so often so it's not completely carrying it's own weight.
• It's possible to adjust the position of the antenna, not just it's elevation.

By combining the support line idea with multiple masts it should be possible to fold the antenna rather than deploy it in a straight line.  It's not easy to come up with a 200 foot long straight section of clear ground.

E-Z Hang Slingshot

This is a stock slingshot that has the fly casting reel added.  It's shown right side up.  You put your hand up through the hole behind the grip.  That way the metal hoop (the foam pad should be moved back to the top of the metal loop) is on top of your arm.  When you pull back the elastic the hoop keeps the grip from rotating backwards.

There is some friction caused by the reel in playing out the mono filament line.  I've read that putting newspapers down in front of the shooting position and playing out a couple hundred feet of line may lower the resistance, but it's a lot of effort to do that and keep from tangling the line.

I used this to get one end of a BWD-90 T2FD up about 90- feet into a pine.  But a couple of years later when the line broke where the tree rubbed aginst it this slingshot was not able to get the line over then now 120 foot tall tree.

CSV17 Tennis Ball Line Launcher

This is a CSV17 tennis ball launcher based on the potato guns made from PVC pipe fittings.
This set includes an assembled launcher with air pressure gauge and safety valve. A special line reel to allow the line to play out with minimal friction and tennis balls fitted with 90 # test stainless steel loops and weighted for better throw.  Not shown, but included is a short PVC pipe and end fitting to ram the tennis ball into the barrel.

A small air comprerssor is on the way and next spring this should put a line over the tall tree.

Line Launcher

4741243 Line Launcher, Billy G. Snider, May 3, 1988, 89/1.34 ; 102/504 - line contained in round fired from flare pistol, can make second, third, etc. attempts quickly

Calls:
The following all have the line at the launch point, not in the round
229058 Line Throwing Gun, L.W. Spencer, Jun 1880, 89/1.34 ; 89/1.1; 89/19 - line pulled through chamber and barrel
932270 LIFE-SAVING AND SIGNAL ROCKET,  P.H. Goodwin, Aug 1909, 89/1.815 ; 102/336; 102/504; 89/1.34; 89/40.06 -
1322601 LINE-CARRYING PROJECTILE,  Nov 1919, 102/504 ; 89/1.34; 89/37.05 - notch in projectile and hinged link allows line to be brought out front of barrel
1418964 Line Throwing Apparatus, C. Norman (BSA Guns, UK), Jun 6 1922, 102/504 ; 89/1.34; 89/37.05 - cylinder holds line and mounts coaxially with gun barrel
3505926 Line Throwing Device, A.M. Johnson (Scientific Prod Corp), Apr 14 1970, 89/1.34 ; 102/504; 42/105- similar to the hand held dog training duck launchers
3583087 LINE THROWING GUN AND CARTRIDGE, Jun 1971 - sub-caliber adapter for shotgun
1072968 Means for Carrying Life Lines, Sep 1913 - cannon for throwing life lines on ship
1072969 Means for Carrying Life Lines, Sep 1913 -cannon for throwing life lines on ship - line in projectile
2373364 Bolas Projectile, Apr 1945 - type of anti aircraft shell that has spreading wires
3780662 RADAR REFLECTOR DEPLOYMENT METHOD, Dec 1973 - rocket unspools long metalized glass fiber
3863380 ILLUMINATED FISHING LURE WITH LINE ATTACHMENT, Feb 1975
3918190 METHOD FOR ILLUMINATING ORGANIC Nov 1975
4326657 Optical fiber dispenser Apr 27, 1982
4649660 Fishing float assembly Mar 17, 1987
4653379 Filament deployment means Mar 31, 1987
4656945 Helicopter destruction system employing cables Apr 14, 1987

You can't see all of the antenna from any single location so it's very difficult to photograph.  Having green coated wires and a green forest background also makes it difficult to see.

Red: top of the delta loop radiating wires. Green: mast guy ropes and Catnary Rope Assemblies Gray: bottom of loop 78' (ground) wires. The guy stakes are in a square pattern 55' on a side.	Looking East before sunset.
Mast Head The four terminals on the BALUN box have phase angles of 0, 90, 180 & 270 degrees and it's important that they are connected sequentially to the four antenna wires.  Hence the blue tape flags.

Intended for ground and sky wave with omnidirectional pattern.  Radiating element consists of two fan-delta curtains supported on a common tubular aluminum mast and placed at 90 degrees to each other.  Each delta is driven by its own balun which, in turn, is driven by a power divider and 90 degree hybrid network.  Features: Fast erection and EMP protection.

One of the places this antenna was used is the TRC-179 Force Terminal is part of the "Regency Net" Communications system.  The AN/GRC-215 Team Terminal is another part of the system.

For more about the TRC-179 see: Mark's Green Pages: AN/TRC-179 "Regency Net" HF/SSB Transmitter/Receiver

Communications Terminal AN/TRC-179(V)1 (NSN 5895-01-156-0411) and
Communications Terminal AN/TRC-179(V)3 (5895-01-202-8672)
TM 11-5895-1218-12

Photos

The three packages: 1: 23" (L) x 21" (W) x 21" (H) 2: 27"(L) x 24"(W) x 18" (H) 3: 7' 7" (L) x 16" (W) x 7" (H)
1 Spools
2 Antenna, Guys, Stakes, Matching Box, etc. The CY-1110/GGC shipping container is for a AN/GGC-3A Teletypewriter.
3 Mast & Gin Pole

Description

The antenna consists of two crossed delta loops.  The bottom of each loop is 78 feet long (Item 18).  These are at right angles to each other and where they cross are connected toghther and to ground.  At the center of the bottom is a grounded 30' mast (Items 6, 7, 8 & 9). If it was a single wire loop the top two elements would each be 50 feet long and the total loop length would be 78 + 50 + 50 = 178 feet (54 meters) which is a wavelength at 5.5 MHz or a half wave at 2.7 MHz.  But each of the top legs of the delta is composed of two wires that are longer than 50 feet that have an insulating rope (Item 22) attached at their midpoints.  So the loop length is a little longer (maybe a half wave at 2 MHz).  There are four antenna ends at the top of the mast that are connected to four seperate teminals on the feed BALUN - hybrid assembly (Item 4).  It has a 50 Ohm feed line and outputs at 0, 90, 180 and 270 degrees relative phase that feed the four antenna elements.  In order to work as a hybrid the assembly includes a couple of high power resistors.

Bill Of Materials

Item	Description	A p/n	p/n	Qty
1
2
3
4	Balun Box			1
5
6	Base Plate	A3032633	1046-ASY-01A	1
7	Mast #4 (Bottom)	A3032630
8	Mast #3, #2	A3032636		2
9	Mast #1 (top)	A3032641
10
11	Gin Pole, Handle Assy
12	Reel 1	A3032718
13	Reel 2	A3032719
14	Radiator Assy Reel1-2	A3032738-1	512-RAD-01A	1
15	Radiator Assy  Reel1-1	A3032738-2	512-RAD-02A	1
16	Radiator Assy Reel2-2	A3032738-3	512-RAD-03A	1
17	Radiator Assy Reel2-1	A3032738-4	512-RAD-04A	1
18	Bare Gnd Wire 78' Reel1-3, Reel2-3			2
19	55' Layout Wire	A3032623	427-WIR-01A	1
20	Guy Rope		865-GUY-01A	4
21	Erection Rope		365-GUY-03A	1
22	Catnary Rope Assy	A3032640	483-CAT-01A	4
23	Curtain Tension Ropes		021-TIE-01A	4
24	Mast Coax	A3032624	253-CBL-01A	1
25
26	Guy Stake (Anchor Bolt)	A3032720		4
27	Base Plate Stake	A3032625		3
28	Base Plate  Stake w/Wire Term	A3032626		1
29	Bar, Wire Reel	A3032621
30	CG-3874/TRC-179(V) 150' Coax
31	2# (32 oz) Hammer	A3032721
32	Bag 1	A3032722-1		1
33	Bag 2	A3032722-2		1
34	Mast Shipping Straps	A3032672-2		2
35	Mast Shipping Spacers	A3086743		2
	Guy Tie Wire	A3032639		4

Installation

There are a couple of fine points I'd like to add.  First is to position the coax on the North side of the mast to protect it from the summer sun.  Second the intersection of the two ground wires is offset from the hinge point of the mast on the base plate.  It would be good for the mast starting position on the ground was on the opposite side of the hinge point so that the guy ropes will be slack until the mast is erect.  This is a non issue when the guy anchor points are made at 0, 90, 180 and 270 degrees all centered on the mast pivot.

		The coax is facing North, will be shielded from Noon Sun. But . . Mast is on wrong side of base plate, it needs to be disconnected and moved so it's pointing East.
Leitz 115A transit setup over mast pivot. Top pivot set to 0. Bottom pivot aimed to the West stake (where mast is pointing).  Then bottom locked and  top turned to 90 degrees. The South stake can be seen through the transit. (to the left of it's eyeball location) This stake was off a few feet. Plumb bob is over hinge.		The North eyeball stake was off maybe 6 to 10 feet.  It makes sense. The West stake was located using the mast as a pointer.  And back sighting to the East stake was good to a foot or so. But eyeballing the North or South stakes requires measuring an angle is where the problems show up.  The tall stake on the right is the eyeball North and the one to the left is the transit located one.
All the mast sections are in place, but neither the BALUN nor antenna wires have been attached. The vertical green rope is used to pull down the hinged mast. The red thing about 6 feet above the ground on the main mast is a fence post level that makes it easy to plumb the mast. The Oak tree has some very small branches touching to top of the mast.  Tips of Oak tree branches at top of Gin Pole.
BALUN has 4 antenna terninals and 4 wire antenna support snaps (same as guy rope snaps). The 4 terminals (1, 2, 3 & 4) have phase relation (0, 90, 180 & 270 deg) making for a circular polarization signal.		Detail of Guy rope at anchors. Snap ring looped through Anchor bolt then 3 times the rope has been put through the snap. Anchor to Left                                                     Mast to Right.
It turns out that the small tree branches foul the antenna wires and prevent properly getting them in position.  So the base has been relocated by taking the mast down to the ground,and rotating the mast about the BALUN so the base is now about six feet from where it started and well clear of the tree.  This required, pulling the mast base stakes (with a five foot TV mast), disconnecting the shourt guy rope at it's anchor bolt, then the ground wires were re-positioned, the guy bolts pulled (w/TV mast).  I discovered the type-N cable that runs from the BALUN to the base of the mast is defective when installing it, but because of the tree problem decided to bring it inside for repair rather than make the repair outside.
		I had downloaded the installation instructions for the UG-1185 type-N male coax plug, took the photo at far left and confirmed that the connector could be rotated on the coax, then opened it up in preraration to making the repair. But I lucked out, instead of finding a bunch of short shield wires inside, everything looks OK.  There was a clue in that it was very easy to open. The problem was the clamp nut was loose.
	Before tilting mast up blue tape flags (1, 2, 3 & 4) were put on the wires so they could be identified from the ground.
East (2) Anchor Wiring Detail	Plumb Mast using fence post level.
The 100 foot coax cable reaches from the antenna to just past my front door, but is about 20 feet short of making it to the rack mounted HP 4395A Network - Spectrum - Impedance Analyzer.  Wouldn't you know I'm missing the adapter needed to connect the two cables and Radio Shack no longer carries it (Type-N female-female barrel).  For lack of a horseshoe nail . . .

Spectrum Analyzer Plots

Made with HP 4395 10 Jan 2012 starting about 5:30 pm PST.

6 pm	Noon
0 to 300 kHz This is amazing performance what a signal at 24.75 kHz is seen and WWVB at 60 kHz is about 20 dB above the noise at 8 pm local time.	0 to 300 kHz
Medium Frequency 300 kHz to 3 MHz KUKI the local AM station at 1.4000 is the strongest.	Medium Frequency 300 kHz to 3 MHz
2 to 5 MHz 3.53 MHz is the strongest signal	2 to 5 MHz
5 to 10 Mhz 7.3875 MHz is the strongest signal	5 to 10 Mhz
10 to 15 MHz Strongest signal at 13.66875 MHz (13.670?) Band quieter, shifted power level reference from -10 dBm to -40 dBm.
15 to 20 MHz Strongest signal 15.325 Mhz.	15 to 20 MHz
20 to 25 MHz Strongest signal at 23.6 with WWV at 25 not far below	20 to 25 MHz This plot was saved before it finished.  Notice the right 2-1/2 squares are the same as the plot above and you can see the up arrow cursor.
25 to 30 MHz Strongest signal 26.4 Mhz with WWV at 25 MHz not far below.

Wire Antenna Patents

4498084 Four wire dual mode spiral antenna, William L. Werner, Raymond H. DuHamel (TCI), Feb 5, 1985, 343/792.5; 343/891; 343/895
3618109 Atenna Construction with Effectively Extended Radiator Elements, William L. Wermer (Grainger Assoc), Nov 2 1971,
3368319 Tall Column Structure of Connected Sections with Warren Cross-bracing and Legs of Channel Section, Werner & Thomas (Grainger Assoc), Feb 13 1968,

AS-2259 - NVIS antenna
AT-984/G - Reel of wire intended for VHF half Rombic antenna
B&W Broadband Folded Dipole Antennas - T2FD type
SORAK - Kit that makes a number of antennas
GRA-4 - Two mast kit, no antenna
GRA-12 - Three mast kit, no antenna
GRA-50 - Variable Dipole Kit with no masts