Wire Antennas

Brooke Clarke, N6GCE 2008 - 2010

Camo Net Masts
                  as received
Components of
                  Camo Net Mast System
as received
components of one bag
12 Al poles, 6 spreaders, 18 stakes

Description of the Camouflage Screening Support System
Mast Section Description
    AB-1089 Does NOT Fit
    How Used for Camouflage Screen
    Antenna Mast Spike Base, NEW, 1.5 and 1-5/8 OD GRC Ham
Wire antenna Use
    Parts Needed
    Idea on Supporting BWD-180
Line Launchers
    E-Z Hang Slingshot
    CSV17 Tennis Ball Line Launcher
    Kongsberg M52
    Type 89 Knee Mortar
    Launched Grapnel Hook
     Air Boss
     PCP Tanks
TCI 651T
    Bill of Material
    Spectrum Analyzer Plots
    Coax Problem
        Direct Burial + UV Resistant
        Wire Antenna Patents
Other Wire Antennas


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 these Camouflage poles may be a lower cost alternative.

Description of the Camouflage Screening Support System

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 transparent 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
Lot # 054

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

Mast Section Description

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 swag rings that lock these together.

AB-1089 Does NOT Fit

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.
                drawing AB-1089/U
                Antenna Mast Tripod Hub

How Used for Camouflage Screen

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

The above title is taken from the eBay auction where this was being sold.  The 1.5" OD section of the base fits the mast base.  It's similar to the AB-154/U Spike Base (What is the O.D. of the AB-154?  let me know).  Maybe they made these by turning the AB-154 in a lathe?
Antenna Mast
          Spike Base, 1.5 and 1-5/8 OD


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

Wire Antenna Use

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:
Camouflage Mast
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.

Idea on Supporting BWD-180

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:
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.

Line Launchers - Getting Wire Up  Into Trees

With the availability of the DJI quad copters, like the Mavic mini 2, the below attempts seem way out of date.  The DJI can easily go up many hundreds of feet with precision control and easily lift a pilot line.

E-Z Hang Slingshot

E-Z Hang SlingshotThis 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 against it this slingshot was not able to get the line over then now 120 foot tall tree.

2672857 Arm-supported slingshot, Albert H Gauthier, 1954-03-23, -
3901209 Wrist braced slingshot, Robert Woolsey, Wallace C Kerr, L&R Inc, IHO Holding, 1975-08-26, -
4606512 Bimodal fishing reel assembly, Robert R. Dennison, 1986-08-19, - one of the modes pulls the line off the face of the reel, but the reel axle is still at right angles to the rod, unlike the reel shown here were the reel axle and parallel with the rod.

CSV17 Tennis Ball Line Launcher

CSV17 Tennis Ball
        Line LauncherThis 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.

Golf Ball Launchers may be another way of launching a line.  Although I haven't seen one that included a provision for a line.  If you know of one please let me know.
Another option may be to replace the compressed air storage tank and valve with a chamber that would hold a construction .22 blank cartridge.

Kongsberg M52

YouTube: Kongsberg M52: A Line-Throwing Rifle (or Harpoon Gun), 8:38 -
Did not find a patent for this.


Line Launcher


203274 Line-throwing apparatus, Edmund S. Hunt, 1878-05-07, - gunpowder fires a shot from tube
305873 Line-throwing gun, Jeremiah Williams, 1884-09-30, - harpoon gun
310852 Line throwing projectile, Philander B. Boys, 1885-01-13. - rocket
331792 Gun and projectile for throwing life-lines, Simon Ingersoll, 1885-12-08, - specialized rifle
348848 Projectile for Throwing Life Lines, Simon Ingersoll, 1886-09-07, - specialized rifle
797613 Line-throwing apparatus, William Schermuly, 1905-08-22, - mount for rocket and line

1418964 Line-throwing apparatus, Norman George, B S A Guns Ltd, 1922-06-06, - attachments to rifle
1575321 Line-throwing gun, Gregory C Davison, Cecil P Caulkins, American Ordnance, 1926-03-02, - has the look and feel of an antique field mortar
2069276 Life line projectile, Ryan Michael J, Feb 2, 1937, 102/504 - line connects on parallel rod to improve flight characteristics2111374 Line throwing mechanism for pistols - See Sedgley patents
2388749 Cord holder for line throwing guns, Pierre Alfred T La, Harrington & Richardson Arms, App: 1944-12-19, W.W.II, Pub: 1945-11-13, - can with specially wound cord - cited by 7
2420347 Line throwing gun kit, Joseph W Baldwin, Harrington & Richardson Arms, App: 1944-12-19, W.W.II, Pub: 1947-05-13, -  rifle, projectiles, line, &Etc. fitted into a suitcase.
2789465 Self-propelled harpoon gun, James H Mcdonald, 1957-04-23, -
3382859 Line-throwing gun, Myers Klingman Edward, 1968-05-14, - for electrical construction
3583087 Line throwing gun and cartridge, George W Huebner, Harrington & Richardson Arms, 1971-06-08, - uses shotgun blank cartridge, cited by 33
4505179 Line throwing device, Steve Nelson, Frank Reynolds, George E. Roos, John Ball, Walker Corp, 1985-03-19, - add-on to riot shotgun

4799906 Rescue apparatus, Benjamin F. Perkins, Jr., Technical Equipment Associates Of Florida, Inc., Jan 24, 1989, 441/85, 89/1.34, 102/504, 441/92 - special rifle with closed end barrel that has ports so it can not be used as a weapon.

5546863 Line carrying projectile, Edward Joslyn, O. F. Mossberg & Sons, Inc., Aug 20, 1996, 102/504, 102/513, 102/336, 89/1.34, 42/105, 102/483  - fits bore of 12 Ga shotgun, bottle with line and light stick.


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
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 coaxial with gun barrel
patent 505926 Line Throwing Device

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
                Uses the same spigot and dog training dummy as the Retriv-R-Trainer plus adds a canister of interiorly wound line.
                shoulder stock also contains a latch type trigger release that works with the knob at the bottom of the Retriv-R-Trainer.
Called by:
4077349 Line boy Mar 7, 1978 - permanently boat mounted for throwing lines to dock
4098015 Retriever training gun with pistol type handle Jul 4, 1978


3004360 Target Projecting Device Utilizing a Can and a Blank Cartridge, A.M. Johnson, Oct 196, 42/105 ; 42/34 - beer or soda can shooter - Basis for the Retriv-R-Trainer

The RL Line Launcher is based on a dog training device but adds a line in a bottle that's rewindable.  But . . .  $500 (2015)

3186119 DEVICE FOR PROJECTING AN AERIAL TARGET, Jun 1965 42/105 ; 124/41.1; 42/98; 42/99- magnet holds tin beer can launched from revolver shooting blanks
3415438 DEVICES FOR PREVENTING DROP-FIRE, (United Shoe Machinery), Dec 1968 - safety device for explosive fastener driver
3505926 Apr 1970 <see above>
3534492 FIREARM GRENADE LAUNCHING ATTACHMENT, S.A. Amster (Federal Labs), Oct 20 1970, 42/105 - smoke can type grenade launcher
3623257 RIFLE HAND GRIP DEVICE, Nov 1971 - vertical grip on forend of rifle
3656399 STOCK AND TRIGGER MECHANISM FOR LINE THROWER, O.W. Hill, Apr 1972 89/1.34 ; 42/105; 42/72 - works with line thrower that looks like retriever dog trainer
3672084 REINFORCED PISTOL GRIP, Frank A. Pachmayr (Mershon Co), Jun 1972 - rubber molded over sheet metal stamping
4154013 Device for training retriever dogs May 15, 1979 - pistol type
2883781 Combination Stabilizer, Recoil Break, Flash Hider, and Gernade Launcher for a Firearm E.M. Harvey (Army), Apr 1959, 42/105 ; 89/14.3 -
3004360 <see elsewhere>
3186119 <see elsewhere>
3392469 METHOD OF OPERATING A REVOLVER FOR SHOOTING A PROJECTILE ATTACHED ON THE Outside of the Barrel Thereof, U. Dubini,  Jul 1968 -
3505926 <see elsewhere>
3731418 SMALL FIREARMS WITH EXCHANGEABLE Barrel, M. Biekenhagen, May 1973, -
4307529 Remote control bumper launcher for training retrieving dogs Dec 29, 1981
4341030 Hunting dog training device, R.L. Little (Little Launcher), Jul 27, 1982 - replacement barrel for pistol
2432539 Grenade Launching Tube and Auxiliary Cartridge Therefor, C.R. Olsen, Dec 16 1947, - maybe spigot for M14 Rifle
2883781 <see eleswhere>
3004360 <see elsewhere>
3007271 Device for Throwing Grenades by means of Firearms, E.W. Brandt, Nov 1961, - to work with rifles fitted with flash suppressors
3176422 <see elsewhere>
3186119 <see elsewhere>
3243909 Grenade Launcher, N. Kotikov, Apr 1966, - for use with cylinder bored shotguns (riot guns)
3392469 <see elsewhere>
3415438 <see elsewhere>
3505926 <see elsewhere>
3534492 <see elsewhere>
3623257 <see elsewhere>
3656399 <see elsewhere>
3672084 <see elsewhere>
3713394 SMOKE SIGNAL DEVICE, (Navy) 102/334 ; 42/105 - fits over revolver barrel
3717946 DEVICE FOR SHOOTING A PROJECTILE, - fits revolver and works with ball ammunition instead of blanks
3731418 <see elsewhere>
3981225 Launcher arrangement for rocket powered round
4098015 Retriever training gun with pistol type handle
4154013 Device for training retriever dogs
D290731 Buoy marker launcher, Albert E. Canady Jul 7, 1987
4263835 Sonobuoy launcher system (Navy) Apr 28, 1981- A pneumatic restraint and ejection system
4279025 Releasable airborne buoy Jul 14, 1981
4718320 Towed decoy system Jan 12, 1988
4741243 <see first patent>
4784035 Remotely actuated tow line throwing device Nov 15, 1988
4799906 Rescue apparatus Jan 24, 1989 - rifle custom made firing blanks, spool on gun
4852455 Decoy system Aug 1, 1989 - spool in projectile with axis coaxial with centerline
4912869 Net gun Apr 3, 1990 - four barreled rifle
5460155 Behavior deterrence and crowd management Oct 24, 1995 - very similar to the retriever launcher, but can have taser wires spooled from projectile
5592770 Shotgun mounted launching device and launching projectile Jan 14, 1997 - spigot attaches to choke threads on shotgun for retriever dog training
5811713 Apparatus for launching projectiles Sep 22, 1998 - spigot attaches to choke threads on shotgun
5915694 Decoy utilizing infrared special material Jun 29, 1999
6116606 High speed glide target Sep 12, 2000
6244261 Line installation tool Jun 12, 2001 - pneumatic rifle type launcher
6499407 Packaging method for infrared special material Dec 31, 2002
6510798 Packaging method for infrared special material Jan 28, 2003
6571714 Silicon window infrared augmenter Jun 3, 2003
6634299 Gas generator Oct 21, 2003 (TRW) - for air bag
3583087 LINE THROWING GUN AND CARTRIDGE, Jun 1971 - sub-caliber adapter for shotgun or use shotgun blank
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
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

Type 89 Knee Mortar

Type 89 Knee Mortar Interesting way to adjust range - might work for a tennis ball line thrower.

Launched Grappling Hook

These are intended to be used for clearing trip wire mines (de mining, land mines).  But might be used just as a line launcher.
It's intended to be launched from any of the M16 - M4 style rifles.  The first time it's used a nornal ball round can be used, but all subsequent rounds need to be .223 blanks. 

Fig 1
Launched Grappling Hook
Fig 2
Launched Grappling Hook
Fig 3 rear bore is about 22mm (0.865")
Launched Grappling Hook
Fig 4 standard 1/4" hex, but extremely tight
Launched Grappling Hook

2388749 Cord holder for line throwing gun, Pierre Alfred T La, Harrington & Richardson Arms C, 1945-11-13 -  container for holding the cord for a line throwing gun.

Air Boss

This is an air powered line shooter that uses a 2 oz lead weight as the bullet.  That's to say the PVC pipe used as the barrel has an I.D. that's just a little larger than the OD of the lead weight.  He uses a simple 90 degree ball valve to release the air rather than the more complex-expensive sprinkler valve as used on the Tennis Ball Line Launcher above.  Sells for about $60 but that includes neither the fishing reel nor line.


Pre-Charged Pneumatic (Wiki: PCP) air guns come in two varieties.  Some have built-in air tanks, and some use external replaceable air tanks.  Then there are larger SCUBA tanks used to charge the gun or it can be charged using a high pressure air compressor.  There is also the very common 12g CO2 Powerlet cartridges (Wiki) used for BB and pellet guns.  These tanks may be the basis of a line launcher.  Another possible source of propellant is from the world of Paintball (Wiki).

After reading about the Airsoft situation and how liquid CO2 causes a number of problems, the compressed air tanks for PCP air guns or the HPA (Wiki: High Pressure Air) tanks for Airsoft seem like a better way to go. 

The Alloy tanks are lower in cost than the carbon fiber tanks.

Al 0.25
Al 0.30
Al 0.5

SCUBA Tanks (Wiki) are between 3 and 18 liters water capacity in size.

TCI 651T H.F. Antenna

TCI 651T Antenna diagram 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.
Where the two sides of a delta loop join they also connect to the ground wire.
From that point there's a green insulating rope to the corner stake (the drawing above shows
red wire going to the ground stake, but that's a drawing error.

The horizontal green insulating rope ties between adjacent delta loops are about 8 feet long.
If you look at the central angel between the top delta loop wires they are all about 45 deg apart.
651T (MIL AS-3791/G) and F

The antenna is intended for ground wave and sky wave communications with omnidirectional coverage; the application for sky wave communications is over short-to-medium ranges.

The radiating element consists of two fan-delta curtains supported on a common tubular aluminum mast and placed at 90 to each other. Each delta is driven by its own balun which, in turn, is driven by a power divider and 90 hybrid network. A lightweight aluminum tilt-up mast permits fast erection.

A special feature of the Model 651 is the care taken to provide EMP (White paper) protection in accordance with the requirements of  DRCPM-8223. This protection is given by good grounding, the use of pulse arrestors across the balanced terminals of the matching units, and a robust design able to withstand high voltages with a margin of safety.

These features and the construction materials make the antenna fully suitable for military and emergency type applications.

Model 651T (MIL AS-3791/G) & F
Polarization..............................Vertical, Circular Hor. comp.
Impedance ............................... 50 ohms nominal
VSWR ....................................... 1.5:1 maximum
Frequency................................ 230 MHz
Power Handling ....................... 400 Watts Avg/PEP
Mast Height.............................. 27.5 ft (8.4m)
Environmental ......................... 100 mi/h (160 km/h) no ice
Performance ............................ 60 mi/h (96 km/h) 1/2 radial ice
Erection Time 651T ................. 1 hour, 4 men
The vertical pattern at low frequencies where NVIS mode works all show signal going straight up, but the 650 in the same data sheet shows nulls straight up.
TCI 651T antenna horizontal & vertical
650T & F



Click on pattern image to see larger image.

When looking at the return loss of the antenna from 0.1 to 50 MHz it's below 10 dB, better than 2:1 VSWR.  This is true for much higher frequencies.
The toroid inductors in the mast head network make a lower limit on good match around 700 kHz.
But, just because the match is good over a very wide range of frequencies that does not mean the antenna radiates well over that same range.  Note the mast head matching network contains two very large power resistors.
Return Loss Plot
TCI 651T Antenna Return Loss 0.1 to 50 MHz
June 2018 testing using WSPRlite
see that page for coverage maps on different bands.

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.
                          Antenna label AS-3791/G
Antenna, Broadband
Dsgn. Act. 80063   p/n: A3023748
Contr. No. DAA807-84-C-D0001   s/n: 1nnnA
Mfg. 30103    NSN: 5985-01-254-0698

Looking East before sunset.
TCI 651T
                  Antenna photo taken at 3:30 pm with sun at my back

TCI 651T Antenna
                  Overall View
TCI 651T Antenna
                  Overall View
Mast Head
TCI 651T H.F.
                  Antenna Mast Head Balun Phase Box
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 which 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


TCI 651T
                  Antenna in shipping packaging
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)

Pkg. 1. Spools

TCI 651T H.F.
                  Antenna Spools

Pkg. 2. Antenna, Guys, Stakes, Matching Box, etc.

The CY-1110/GGC shipping container is for a AN/GGC-3A Teletypewriter.
TCI 651T H.F.
                  Antenna Wire, Guys, Stakes, Matching Box, etc.

TCI 651T
                  H.F. Antenna Wires, Guys, Base Plate, Hammer, Stakes,
TCI 651T H.F.
                  Antenna Hybrid BALUN Coax to 4 terminals + Ground

TCI 651T
                  H.F. Antenna BALUN Hybrid
Ive received photos of a new phasing box and it too has very similar
melting of the foam.  It may have been some high power test of the
effectiveness of the EMP resistant design, ... or....?
So I doubt that there's any problem with this unit.

Pkg. 3 Mast & Gin Pole

TCI 651T H.F.
                  Antenna Masts & Gin Pole


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 together 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 separate terminals 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
4 Balun Box     1
6 Base Plate A3032633 1046-ASY-01A 1
7 Mast #4 (Bottom) A3032630    
8 Mast #3, #2 A3032636   2
9 Mast #1 (top) A3032641    
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
TCI 651T
                  H.F. Antenna Ground Wire 78'
19 55' Layout Wire
TCI 651T H.F.
                  Antenna Layout Wire 55'
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
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


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.
W TCI 651T
                  Installation Gnd Wires & Mast
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)
TCI 651T
                Guy Anchor location using transit
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.
TCI 651T
                Transit Located Guy Anchors (North)

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.
TCI 651T
                showing Oak branches on Gin Pole
TCI 651T Mast
                  and Guy Ropes in place, no Balun or Antenna wires yet
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.
TCI 651
                  H.F. Antenna BALUN at top of mast before Ant wires and
                  titl up
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.

Correct large
                  caribiner used for rope tension
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.
UG-1185 connector can be rotated
                360 degrees relative to coax cable, maybe bad
UG-1185 is OK.
                  The shield wires are intact. Problem was loose nut.

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 preparation 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.

                  Antenna looking East Balun and Mast

Before tilting mast up blue tape flags (1, 2, 3 & 4) were put on the wires so they could be identified from the ground.

                  Antenna Wire Terminals 1, 2, 3 & 4
East (2) Anchor Wiring Detail
TCI 651T Antenna
                  East (2) Anchor Wiring Detail
Plumb Mast using fence post level.
TCI651T Antenna
                  Mast Plumb

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

There are a lot of signals.  The antenna is working well.  A much better test would be to use it with a chirp receiver, or a regular short wave receiver tuned to each of the NorCal DX beacons.
Made with HP 4395 10 Jan 2012 starting about 5:30 pm PST.
6 pm
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.
TCI 651T
                Antenna HP 4395A Spectrum Analyzer Plot 0 to 300 kHz
0 to 300 kHz

TCI 651T
                Antenna HP 4395A Spectrum Analyzer Plot 0 to 300 kHz

Medium Frequency 300 kHz to 3 MHz
KUKI the local AM station at 1.4000 is the strongest.
TCI 651T
                Antenna HP 4395A Spectrum Analyzer Plot Medium Frequency
                300 kHz to 3 MHz
Medium Frequency 300 kHz to 3 MHz

TCI 651T
                Antenna HP 4395A Spectrum Analyzer Plot Medium Frequency
                300 kHz to 3 MHz

2 to 5 MHz
3.53 MHz is the strongest signal
TCI 651T
                Antenna HP 4395A Spectrum Analyzer Plot 2 to 5 MHz
2 to 5 MHz

TCI 651T
                Antenna HP 4395A Spectrum Analyzer Plot 2 to 5 MHz
5 to 10 Mhz
7.3875 MHz is the strongest signal
TCI 651T
                Antenna HP 4395A Spectrum Analyzer Plot 5 to 10 MHz
5 to 10 Mhz

TCI 651T
                Antenna HP 4395A Spectrum Analyzer Plot 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.
TCI 651T
                Antenna HP 4395A Spectrum Analyzer Plot 10 to 15 MHz

TCI 651T
                Antenna HP 4395A Spectrum Analyzer Plot 10 to 15 MHz
15 to 20 MHz
Strongest signal 15.325 Mhz.
TCI 651T
                Antenbna HP 4395A Spectrum Analyzer Plot 15 to 20 MHz
15 to 20 MHz

TCI 651T
                Antenbna HP 4395A Spectrum Analyzer Plot 15 to 20 MHz
20 to 25 MHz
Strongest signal at 23.6 with WWV at 25 not far below
TCI 651T
                Antenna HP 4395A Spectrum Analyzer Plot 20 to 25 MHz
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.

TCI 651T
                Antenna HP 4395A Spectrum Analyzer Plot 20 to 25 MHz

25 to 30 MHz
Strongest signal 26.4 Mhz with WWV at 25 MHz not far below.
TCI 651T
                Antenna HP 4395A Spectrum Analyzer Plot 25 to 30 Mhz

TCI 651T
                Antenna HP 4395A Spectrum Analyzer Plot 25 to 30 Mhz


The ICOM 706 MkII G works with the TCI 651T on the 80 meter army radio net (3996 kHz USB, so the antenna is working OK.
The burned spots in the foam around the toroids indicates over heating, but apparently not permanent damage.

Problem with Coax - July 2013

There are splits in the coax jacetk allowing you to see the shield braid.  At first I thought these were caused by negligent use of the weed mower, but now think it's just the Sun breaking down the jacket.

Raychem Repair

To cover the place where a lot of the jacket is torn I used some Raychem shrink tube.  This tube has an I.D. of about 7/8" and will just clear a type-N male connector, but not the wire ring that holds the end plug which needed to be removed to slip the tube on.  The tube is marked:
Raychem WCSM 20/6 EX20781-13
It has an adhesive on the inside that melts and forms a gray colored bead at the ends after shrinking the tube using an industrial type heat gun.

But this is just a patch.  The long term fix is to get the coax out of the Sun.
Trenching and pulling the coax into conduit is an expensive and back breaking solution with the risk of cutting other in ground utilities (water main, sprinkler pipe, storm drain pipe).
Maybe a better solution is to use pipe insulation sleeves that have a slit along the long dimension?




Humboldt AuxComm

Using HF NVIS for Emergency communications in addition to VHF.
Coden Envoy radios (one at court house, one vehicle mounted).

Direct Burial + UV Resistant

Need to measure how long to order.  Only 5 of the 15 coax types they carry have the needed properties for this application.
Table of DX Engineering Coax Cables that are rated for direct burial and are UV resistant.

Atten dB @ 30 MHz/100'
2ea N(m)
0.405" 0.8
0.242" 1.5
0.405" 1.0
0.405" 0.7

Wire Antenna Patents

6791508 Wideband (NVIS) conical spiral antenna, Sonja A. Berry, James R. Gilbert (Boeing), Jun 6, 2002, 343/895, 343/749, 343/881
                Also interesting 48 citations and referenced by 15 patents.  46' x 105' with 33' central mast
4498084 Four wire dual mode spiral antenna, William L. Werner, Raymond H. DuHamel (TCI), Feb 5, 1985, 343/792.5; 343/891; 343/895 (TCI 545?)
3376577 Vertical radiation spiral antenna, Dean Kennedy Peter (Granger Associates), Nov 15, 1965, 343/886, 343/895 - Vertical sounding 2-15 MHz  30' hi x 200' dia.
                2958081 Unidirectional broadband antenna comprising modified balanced equiangular spiral, Dyson John D (Univ Illinois), Jun 30, 1959, 343/895, 343/908
                              Point is at the top, should be at the bottom (see 3376577 for explanation).
3683390 HF Broadband Omnidirectional Antenna, Cory; William A. Kennedy, Cory; William A. Kennedy (Collins), Aug 8 1972,
class: 343/792.5; 343/798; 343/809; 343/891 - tall mast Log Periodic pointing up
3906509 Circularly Polarized Helix and Spiral, Raymond H. Duhamel, Raymond H. Duhamel (not assigned), Sep 1, 1975, 343/895

3618109 Antenna Construction with Effectively Extended Radiator Elements, William L. Wermer (Grainger Assoc), Nov 2 1971,
343/792.5; 343/802; 343/884; 343/890 - this looks like the gigantic log periodic beam that was later sold by TCI

3368319 Tall Column Structure of Connected Sections with Warren Cross-bracing and Legs of Channel Section, Werner & Thomas (Grainger Assoc), Feb 13 1968,
52/637; 52/148; 52/651.02; 52/694

Other Wire Antennas

Antennas - not just wire
AS-2259 - NVIS antenna
AT-984/G - Reel of wire intended for VHF half Rombic antenna
B&W Broadband Folded Dipole Antennas - T2FD type
Eyring Low Profile Antenna 301A (ELPA 301A)
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


Coleman's Surplus - where I got these titled:  "Support System for Camo Netting" and got the Aluminum poles, not the fiberglass ones
The Mast Company - sells the poles and they have made some accessories like guy rings
Sherill Big Shot Item #LT41001.LT41009,LT41010 - giant slingshot - 120' vertical reach
Tetra Line Thrower - uses special .308W blanks.
WiNRADiO - AX-12B Wide-Band Surveillance Antenna System - covers Band 1: 0.15-30 MHz, Band 2: 30-100 MHz & Band 3: 100-1500 MHz (3ea Type-N connectors)

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