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Message |
    
Big_thunder
Junior Member
Username: Big_thunder
Post Number: 32
Registered: 9-2004
| | Posted on Sunday, January 09, 2005 - 9:38 am: | 
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Hey can anyone tell me how you can determine what tower is 20g or 25g ,45g. I have one of them not sure which one. |
Tech808
Moderator
Username: Tech808
Post Number: 4516
Registered: 8-2002
| | Posted on Sunday, January 09, 2005 - 10:08 am: |
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Big_thunder,
Rohn 25G is 12-1/2" Triangular Design Zig Zag with 1-1/4 Tubing
Rohn 45G is 18" Triangular Design Zip Zag with 1-1/4 tubing
Sorry can't help you with the 20G but it will be a smaller size than the 25G.
Lon
Tech808
CEF808
N9OSN |
Bluegrass
Member
Username: Bluegrass
Post Number: 76
Registered: 12-2004
| | Posted on Sunday, January 09, 2005 - 10:15 am: |
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Well the rohn 25g has a 12 inch face and the 45g i think has a 24 inch face i'm not sure but i do know that the higher the number the larger the face and i am sure the 25g has a 12 inch face so if your tower is smaller then that it's a 20g if it's larger then it's a 45g. |
Big_thunder
Junior Member
Username: Big_thunder
Post Number: 34
Registered: 9-2004
| | Posted on Sunday, January 09, 2005 - 10:28 am: |
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Thanks a lot for the infor. |
Tech833
Moderator
Username: Tech833
Post Number: 937
Registered: 8-2002
| | Posted on Sunday, January 09, 2005 - 10:50 am: |
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20G is not only smaller than 25, it is also made of flat material instead of tubing.
25G has a 12" face and small bracing rod. The legs are 1 1/4" tubing.
45G has a 18" face and 7/16 bracing rod. The legs are 1 1/4" tubing.
55G is identical to 45G except the legs are made of 1 1/2" tubing.
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Bruce
Senior Member
Username: Bruce
Post Number: 2040
Registered: 9-2003
| | Posted on Sunday, January 09, 2005 - 12:50 pm: |
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833 will 20g support a 2 meter array and how far can it go up unguided?
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Big_thunder
Junior Member
Username: Big_thunder
Post Number: 35
Registered: 9-2004
| | Posted on Sunday, January 09, 2005 - 9:55 pm: |
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Will you need guy wire for a 25g tower over 50ft in height? if so what type of guy? |
Tech833
Moderator
Username: Tech833
Post Number: 942
Registered: 8-2002
| | Posted on Tuesday, January 11, 2005 - 2:10 am: |
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According to the Rohn book, for 70 MPH winds, a 25G tower much be guyed if it goes over 35 ft free standing with a 1.7 sq. ft. windload.
Personally, I would guy any Rohn 25G over 20 feet no matter what. For any 'array' with a rotor, I would highly suggest Rohn 45 as a minimum. The 18 inch wide towers are MUCH, MUCH more twist resistant. I have a 40 foot free standing Rohn 55 with a TV antenna and a dual band VHF/UHF on top and it is pretty wiggly when you are working on top of it. |
Big_thunder
Junior Member
Username: Big_thunder
Post Number: 36
Registered: 9-2004
| | Posted on Thursday, January 13, 2005 - 4:57 pm: |
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Hey thanks for the infor. Now what type of guy wire will I need ? |
Ca346
Senior Member
Username: Ca346
Post Number: 1076
Registered: 8-2003
| | Posted on Monday, January 17, 2005 - 1:44 am: |
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I have a Rohn 25G 50 foot tower. It is set in a 4x4x4 concrete base (overkill) alongside my garage/shop. It is strapped to the facia board at the peak of the roof at 14 feet, with three 3/16" guy wires at 25ft and three 3/16" guy wires at 46ft (needed room at the top for a 4 element Quad to move). When I climb that tower, it still moves....
It cost as much for the wires and egg insulators than it did for the old used tower. $$$$
You can do a search on the Rohn tower for specifications, which are available.
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Airplane1
Intermediate Member
Username: Airplane1
Post Number: 262
Registered: 5-2004
| | Posted on Monday, January 17, 2005 - 9:36 am: |
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If your looking for a good self supporting tower then check out the towers from AN wireless, search them on internet. they are located in PA and the prices are unbelevably good for towers and you will see they are built better than Rohn.
I am buying a 30ft self supporting this spring from them.
They also have lots of pics of there towers and assesories.
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Duck246
New member
Username: Duck246
Post Number: 3
Registered: 8-2004
| | Posted on Tuesday, January 18, 2005 - 1:32 am: |
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The tower needs to move ca346. All non free standing towers need to flex a little, the guys just keep it from flexing too much  |
