The AM Forum
April 27, 2024, 08:37:35 PM *
Welcome, Guest. Please login or register.

Login with username, password and session length
 
   Home   Help Calendar Links Staff List Gallery Login Register  
Pages: [1]   Go Down
  Print  
Author Topic: MILITARY fiberglass pole in tree.  (Read 7816 times)
0 Members and 1 Guest are viewing this topic.
ke7trp
Contributing
Member
*
Offline Offline

Posts: 3659



« on: November 06, 2010, 03:43:27 PM »

Ok. This morning, We put the fiberglass pole up in the pine tree to support LEG B of the open wire antenna.  I found a local Tree service guy willing to do the work.  He V cut the tree so the mast would go flush to the trunk. We used Camo ratchet straps to hold the mast to the tree. 

Things to know:

1.  You can buy this pole for about $80 shipped with the dipole hanger and guy rings. 
2.  The sections DO NOT lock in,  So you cannot pull the mast UP or the joints will slip. Use tape to secure the sections.
3.  These poles are not very sturdy. They will hold a wire but the sections are only 4 ft each so you really need support ropes.
4.  Tie a rope to the top of the dipole hanger and then pull that rope downward and tie it off to a Tree limb or other support, This will stop the wind from picking the mast up and seperating it.

The antenna is now up flat top.  15 ft of turn down each leg.  Propbably around 50 ft. Its working well now.  Next week, We will put another pole in another pine and move LEG A. of the antenna over away from the vertical.  This will also stretch the antenna out a bit so it will have only 5 ft of turn down. 

Sometimes you have to make major compromises.  I lost my tower in the storm so this is what I came up with to get back on the air with a decent antenna.  Cant wait to try it out tonight. East coast AM has been comming strong late at night.

C


* tree1.jpg (332.01 KB, 781x1306 - viewed 574 times.)

* TREE2.jpg (249.02 KB, 781x1306 - viewed 509 times.)
Logged
Steve - WB3HUZ
Guest
« Reply #1 on: November 08, 2010, 09:12:08 AM »

Curious as to why you didn't put the mast above the top of the tree. Seems no height advantage was gained.
Logged
w3jn
Johnny Novice
Administrator
Member

Offline Offline

Posts: 4619



« Reply #2 on: November 08, 2010, 11:47:51 AM »

SHould you tell him about those fiberglass masts, or should I, Steve   Cry
Logged

FCC:  "The record is devoid of a demonstrated nexus between Morse code proficiency and on-the-air conduct."
W1RKW
Contributing
Member
*
Offline Offline

Posts: 4412



« Reply #3 on: November 08, 2010, 03:57:32 PM »

Is that Thing from the Addams Family sitting on the branch helping you?  Grin
Logged

Bob
W1RKW
Home of GORT.
ke7trp
Contributing
Member
*
Offline Offline

Posts: 3659



« Reply #4 on: November 09, 2010, 11:23:20 AM »

Curious as to why you didn't put the mast above the top of the tree. Seems no height advantage was gained.

It is out of the top of three. That picture does not really show it.  The top of that tree is really thin.  Going much higher would leave 2 or more sections not supported. Also. I wanted it equal and flat to match the other side. These poles are not strong enough in the high winds we see to even go two sections not supported.

This pole allowed me to go another 20 ft or so over just rope in the tree. Also the wire is no longer touching the branches which will help when it rains.

ITs working pretty good like this. I was able to key down over a certain someone that skipped me in the rotatation on friday when robert was out there on 3885.. LOL  Really irritating to wait 30 minutes in rotatation and then get skipped. Robert heard, me, Laughed and I signed off.  east coast is booming in late at night now.

I am going to now move the other side of the wire to a different pine.  This will allow more flat top wire and not so much turn down and it will get the wire away from the vertical.  This time, I am going to use a square 20ft pipe out of the top of the tree. The military poles are really neat, They are also cheap.  For a center support of an inverted V, They would work great.

C
Logged
Steve - WB3HUZ
Guest
« Reply #5 on: November 09, 2010, 02:31:38 PM »

Good deal. The higher and flatter you can make the wire, the better.

There are also aluminum versions of those masts. These are quite a bit stronger (although somewhat heavier) than the fiber ones. I was impressed with these aluminum masts at the NEARFest. Tron used 4-5 sections to hold up three big PA horns. THe mast flexed to nearly a 45 degree angle when we lifted the assembly off the ground but it didn't break. And there no lasting affects when we got the mast up to vertical.
Logged
K1JJ
Contributing
Member
*
Offline Offline

Posts: 8893


"Let's go kayaking, Tommy!" - Yaz


« Reply #6 on: November 09, 2010, 02:42:27 PM »

That 3" diameter PVC pipe can make pretty good masting too. Schedule 40 is OK but schedule 80 is as strong as steel... Wink

They sell it in 20' lengths at the yards, though 10' is more common.  I remember when we put up Craig's 100' 45G tower we used this for the side antennna wire supports. Very strapping stuff when sched 80.  We actually telescoped it down to 2.5" making a 40' guyed mast IIRC.   Push this up a tree and you're golden.

T
Logged

Use an "AM Courtesy Filter" to limit transmit audio bandwidth  +-4.5 KHz, +-6.0 KHz or +-8.0 KHz when needed.  Easily done in DSP.

Wise Words : "I'm as old as I've ever been... and I'm as young as I'll ever be."

There's nothing like an old dog.
ke7trp
Contributing
Member
*
Offline Offline

Posts: 3659



« Reply #7 on: November 09, 2010, 03:14:22 PM »

The tree service guy suggested we go down to the local metal scrap yard. They sell hundreds of types and lengths of pipe. He suggested we get a 20 ft Square section and put it in the far tree. This could be up 10 ft over the top and that tree is much thicker. 

Had I known about the aluminum masts, I would have purchased one steve, Do you know where I can get one?

I need to move the wire over, Its really interacting with the vertical now.  I have to short the feeders on the wire antenna or the vertical shows SWR and is really down on performance.

C
Logged
W1UJR
Guest
« Reply #8 on: November 09, 2010, 03:18:03 PM »


Had I known about the aluminum masts, I would have purchased one steve, Do you know where I can get one?


Try Ben -->> http://www.ontariosurplus.com/masts.htm
Logged
W7SOE
Contributing
Member
*
Offline Offline

Posts: 813



« Reply #9 on: November 09, 2010, 05:56:08 PM »

SHould you tell him about those fiberglass masts, or should I, Steve   Cry

spill it!  ;-)
Logged
Jeff W9GY
Member

Offline Offline

Posts: 257



« Reply #10 on: November 09, 2010, 06:00:03 PM »

I lashed one of those military fiberglass poles to a small tree at our place in the Upper Peninsula.  I chickened out ---one 4 foot section not installed.  Used bungee chord and nylon rope to attach to tree trunk as high as I could reach on a ladder.  It survived a 50 MPH blow before we left for home and when the super low pressure went through (28.20), the winds got to gusts of 65+ MPH over several days.  My sources tell me it's still standing!!
Logged

Jeff  W9GY Calumet, Michigan
(Copper Country)
w3jn
Johnny Novice
Administrator
Member

Offline Offline

Posts: 4619



« Reply #11 on: November 09, 2010, 11:30:31 PM »

SHould you tell him about those fiberglass masts, or should I, Steve   Cry

spill it!  ;-)

OK.... I bought a bunch of those with the welded tripod base and guy rings etc.  HUZ and I fiddled with it for hours trying to raise it vertical but those things had way too much flex and we could never "get it up".  Then they split at the couplings from the stress - I fixed that with hose clamps. 

So plan B was putting a mast in a pine tree similar to Clark's.  Unfortunately the swaying of the pine tree in the wind busted the fiberglass masts all to hell after a short while.

So Plan C was a Radio Shack 10' steel mast strapped into the pine tree.  Even that bent at a 20 degree angle after a few years.

I finally settled for a few feet lower, attached to the pine tree itself with a bit of slop in the lines so the pine tree swaying wouldn't take down the ant.  That's been up for 4 years now, hafta tighten it up every 6 months or so, but it's survived wind and ice storms no problem.

Ant in question is a 130' flat top fan dipole, center fed with W7FG open wire.  Each element of the fan is roughly the same length, and spread about 2-3' at the ends.  It's up about 30'.  Seems to work FB, even on 160.   Undoubtedly it would work a lot better if it were up higher, but that's pretty difficult given the tree situation.
Logged

FCC:  "The record is devoid of a demonstrated nexus between Morse code proficiency and on-the-air conduct."
ke7trp
Contributing
Member
*
Offline Offline

Posts: 3659



« Reply #12 on: November 10, 2010, 11:20:35 AM »

On the fiberglass poles, There is a light duty and a reinforced version.  THe stronger of the two has a plastic or epoxy collar around the bottom so it wont split.  My "kit" had a few HD ones so I put them at the top.  The other thing I did was to put a dacron rope at the top to pull the entire thing downward. This makes a big difference in the strength.  Mine is very rigid in the tree. I can pull the wire antenna right through the top section and it does not sway at all.  Time will tell how this works. For now, I am happy. I wish I got the aluminum poles... I just did not know about them.

C
Logged
W7SOE
Contributing
Member
*
Offline Offline

Posts: 813



« Reply #13 on: November 10, 2010, 11:54:21 AM »

On the fiberglass poles, There is a light duty and a reinforced version.  THe stronger of the two has a plastic or epoxy collar around the bottom so it wont split.  My "kit" had a few HD ones so I put them at the top.  The other thing I did was to put a dacron rope at the top to pull the entire thing downward. This makes a big difference in the strength.  Mine is very rigid in the tree. I can pull the wire antenna right through the top section and it does not sway at all.  Time will tell how this works. For now, I am happy. I wish I got the aluminum poles... I just did not know about them.

C

I think those are the kind I have also, off ebay.  I have about 20 ft of it on my roof no problems.  When I have used trees I alsoo used large springs or bungees on the antenna ends.

Rich
Logged
Steve - WB3HUZ
Guest
« Reply #14 on: November 10, 2010, 12:47:31 PM »

Back guying it was a good move.

On the fiberglass poles, There is a light duty and a reinforced version.  THe stronger of the two has a plastic or epoxy collar around the bottom so it wont split.  My "kit" had a few HD ones so I put them at the top.  The other thing I did was to put a dacron rope at the top to pull the entire thing downward. This makes a big difference in the strength.  Mine is very rigid in the tree. I can pull the wire antenna right through the top section and it does not sway at all.  Time will tell how this works. For now, I am happy. I wish I got the aluminum poles... I just did not know about them.

C
Logged
Pages: [1]   Go Up
  Print  
 
Jump to:  

AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
 AMfone © 2001-2015
Powered by SMF 1.1.21 | SMF © 2015, Simple Machines
Page created in 0.078 seconds with 19 queries.