Wire Antennas

© Brooke Clarke, N6GCE 2008 - 2010

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

Background

Description of the Camouflage Screening Support System

Mast Section Description

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.

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?

Manuals

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:

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

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

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 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

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.

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.

Patents

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 coaxial 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                 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

Calls:

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

Calls:
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>
3176422 ANTI-JAMMING MEANS FOR REVOLVERS, Apr 1965
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

Calls:
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>
3496580 INFLATABLE AND RECOVERABLE LIFESAVING PROJECTILE APPARATUS,
3505926 <see elsewhere>
3534492 <see elsewhere>
3618244  METHOD FOR FIRING PROJECTILES UNDERWATER, - spear gun
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

Calls:
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
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
------------------------------------

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

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.

PCPTanks

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.

Material	Liters	PSI	$
Al	0.22	4500	36
Al	0.25	4500	32
Al	0.30	4500	37
Al	0.5	3000	43
C	0.35	4500	138
C	0.42	4500	135
C	0.58	4500	170
C	0.80	4500	178
C (SCUBA)	3.0	4500	270

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

TCI 651T H.F. Antenna

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.

Specifications Model 651T (MIL AS-3791/G) & F Polarization..............................Vertical, Circular Hor. comp. Impedance ............................... 50 ohms nominal VSWR ....................................... 1.5:1 maximum Frequency................................ 2–30 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.

650T & F 651 653T 653F

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

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, Broadband AS-3791/G 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.
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 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

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)
Pkg. 1. Spools
Pkg. 2. Antenna, Guys, Stakes, Matching Box, etc. The CY-1110/GGC shipping container is for a AN/GGC-3A Teletypewriter.
	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

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 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
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 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.
	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

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	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.

Operation

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?

Other Wire Antennas

Links