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Paper765
New member
Username: Paper765
Post Number: 7
Registered: 12-2004
| | Posted on Saturday, January 08, 2005 - 7:43 pm: | 
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I still need help! The 6 ft radials don't seem to be working. I wrapped some stainless steel wire and streched it out to lengthen the radials, and the swr dropped down to 2.5. Not very good, but better then it was (well over 3). I'm afraid that perhaps Tech833 is right... DO THEY HAVE TO BE 1/4 WAVE RADIALS FOR SURE? If the answer is yes, I'm screwed... I dont know where I'm going to get 9 ft long Aluminum tubing, I think that it comes in 6 and 12 ft lengths mail order, and that the shipping on 12 ft will make the purchase cost prohibitive as it's most certainly an oversized... plus, I don't think that the 12 ft lengths will be self supporting. The whole hope of this project was to get away from using wire radials (which is what I did previously) as this time I'm going to be mounted on a fairly high tower, and I don't want to reclimb the tower to tie new fishing line/weedwacker line/whatever to the radials to pull them out and away from the tower (sort of like a teepee). Let me ask this. Can I run super long metal radials all the way down to the ground?
My previous antenna worked like this. One 9 ft stainless steel whip on a mast, mast attached to chimmney, 4 radials coming off (10 gauge wire) going north south east and west. The radials were attached to a mounting plate (as was the antenna itself). The radials were roughly 9 ft in length, and the ends were tied off with fishing line. The fishing line (non-conductive) then streched the radials to the edges of the roof. This setup worked quite well, as I was able to go over 30 miles barefoot, and had very very good reception. But situations change, I don't live there anymore, and this antenna needs to be on a tower now. So, I wanted to use radial rods instead of the streched wire trick, but as noted above, I'm running into problems using alum rods. |
Tech833
Moderator
Username: Tech833
Post Number: 935
Registered: 8-2002
| | Posted on Sunday, January 09, 2005 - 1:24 am: |
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You don't need aluminum. You can go to your local hardware store and buy some galvanized conduit. It comes in sizes as small as 1/2 inch diameter and lengths of 10 or 20 feet. If you purchase some 20 footers, bolt them right to the tower immediately them below the feedpoint in an X. Otherwise, buy some 10 footers and make some brackets. As an alternative, you could buy a huge TV antenna with a long boom and mount the 1/4 wave whip right on top of it. Then short a bunch of the TV antenna elements to the boom for more ground plane.
BTW, Yes, I was right. Sorry. I wish the physics went more in your favor. |
Kid_vicious
Intermediate Member
Username: Kid_vicious
Post Number: 117
Registered: 9-2004
| | Posted on Sunday, January 09, 2005 - 2:03 am: |
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paper765, just so i dont think that youre ignoring my posts; why cant you use two different diameters of aluminum tubing, buy 6 foot lengths, telescope them, and cut off the excess. if you use the tubing and set up i descibed earlier, it will work great. i promise!
and yes, the radials do have to be 8.5 (102") long, but we have already told you that.
maybe you'd better step in here 833, this guy doesnt believe bruce or me. |
Tech833
Moderator
Username: Tech833
Post Number: 938
Registered: 8-2002
| | Posted on Sunday, January 09, 2005 - 10:52 am: |
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Kid is correct. Endorsement given.
As long as you cut 2" long slots in the end of the larger tubing, you can use hose clamps to hold the inner tubing tight. |
Paper765
New member
Username: Paper765
Post Number: 8
Registered: 12-2004
| | Posted on Sunday, January 09, 2005 - 7:42 pm: |
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Kid,
No please don't take it as me ignoring your posts. I appreciate your advice ..sigh... I guess it's back to the drawing board, I'll have to scrap the mount and start over with the suggestions listed above, or perhaps get the aluminum tubing as you suggest and overlap it on the current rods. I dunno where I can locally get the tubing, I'm out in the sticks. Never saw that sort of thing at home depot or lowes. I'll calm down, gather my thoughts, and see what resources I can come up to work with. The conduit is an interesting idea, but I'll have to scrap my current mount and start fresh.
Thanks for all the ideas guys!
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Kid_vicious
Intermediate Member
Username: Kid_vicious
Post Number: 126
Registered: 9-2004
| | Posted on Monday, January 10, 2005 - 11:43 pm: |
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glad to help dude!
at the home depots around where i live, they have a section where they sell flat strap, angle iron, etc. nothing over a 4 foot length but you might find something there.
another idea would be to use 1/2" pvc pipe and put a piece of thick, solid, copper wire through it. that would give you the radials you are looking for.
good luck
matt |
Nightmarenyc
New member
Username: Nightmarenyc
Post Number: 2
Registered: 1-2005
| | Posted on Tuesday, January 25, 2005 - 2:02 pm: |
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You should check again. I've gotten aluminum tubing from Home Depot in 3 foot lengths that I was able to telescope together for a mobile project I was working on. If your way out in the sticks just call up the store 1st and ask if they have it in stock. Any of the above mentioned suggestions should work also. Good luck! |
Ferd1605
Junior Member
Username: Ferd1605
Post Number: 10
Registered: 1-2005
| | Posted on Tuesday, February 01, 2005 - 5:15 am: |
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Paper765 ... use the conduit as tec833 said .. it is real cheap and available in your area .. just drill holes in it and use " U " bolts to mount it to your mast .. you may also bend the conduit down a bit , like close to 45 % angle to help with matching . Good luck to ya . |
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