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What do you think is the best Omnidirectional antenna for 11 meters ?

180° cable is 1/2λ *k cable cut for desired frequency.
This length of cable transfers load values to input without influence. You can use even RG6 cable to feed your antenna.
For example:
Belden 8267 RG213/U it will be 3,624729 or multiplier.
Belden 9116 RG6 it will be 4,550554 or multiplier.
If you want to know more, download http://www.ac6la.com/tldetails1.html
Mike
 
If I were making a delta loop antenna I'd cut the wire
37 ft. 6 inches, which is too long for 27.205 Mhz.
I'd buy a 6' RG59 A/V cable from Home Depot, etc, and 2 of these adapters -
$_35.jpg
And put the RG59 jumper between the antenna and 50 Ohm coax.

To take SWR readings I would use a RG58 coax section connected to the SWR analyzer end of your RG59 (75 Ohm) jumper that is cut 11' 6" long, or exact multiples of that length - x2=23', x3=34.5', x4=46', etc. Do not hook the MFH-259C to the RG59 jumper. Make sure there is 50 Ohm coax between your analyzer and the 75 Ohm jumper.

After doing all of the above, I'd take my readings of the SWR at ch40 & ch1 and start bending the the loop wire back at one end a little at a time until the SWR lands at its best reading.
As some have said, given your installatiion peculiarities the best SWR may not be as low as you desire, but should be low enough to give you good radioing.

Note: If you are using coax other than RG58, google the velocity factor and multiply 17.2' times the VL of your coax.
 
180° cable is 1/2λ *k cable cut for desired frequency.
This length of cable transfers load values to input without influence. You can use even RG6 cable to feed your antenna.
For example:
Belden 8267 RG213/U it will be 3,624729 or multiplier.
Belden 9116 RG6 it will be 4,550554 or multiplier.
If you want to know more, download http://www.ac6la.com/tldetails1.html
Mike
Right on, Thank you, I will.
 
If I were making a delta loop antenna I'd cut the wire
37 ft. 6 inches, which is too long for 27.205 Mhz.
I'd buy a 6' RG59 A/V cable from Home Depot, etc, and 2 of these adapters -
View attachment 21382
And put the RG59 jumper between the antenna and 50 Ohm coax.

To take SWR readings I would use a RG58 coax section connected to the SWR analyzer end of your RG59 (75 Ohm) jumper that is cut 11' 6" long, or exact multiples of that length - x2=23', x3=34.5', x4=46', etc. Do not hook the MFH-259C to the RG59 jumper. Make sure there is 50 Ohm coax between your analyzer and the 75 Ohm jumper.

After doing all of the above, I'd take my readings of the SWR at ch40 & ch1 and start bending the the loop wire back at one end a little at a time until the SWR lands at its best reading.
As some have said, given your installatiion peculiarities the best SWR may not be as low as you desire, but should be low enough to give you good radioing.

Note: If you are using coax other than RG58, google the velocity factor and multiply 17.2' times the VL of your coax.
Thank you very much, I have a lot to learn.
 
Peak is 42 feet to the ground, I can go no higher then 10 ft over roof line
My imax 2000 is 10' from feed point to ground and it works. Any of the popular 11 meter antennas 10' over a 40' roof line should work famously. I think what you need to decide is whether aluminum or a metal alloy type over a fiberglass one should be the question, considering you have a metal roof. After that you should be hearing and getting out tremendously. 73
 
My imax 2000 is 10' front feed point to ground and it works. Any of the popular 11 meter antennas 10' over a 40' roof line should work famously. I think what you need to decide is whether aluminum or a metal alloy type over a fiberglass one would be the question considering you have a metal roof. After that you should be hearing and getting out tremendously. 73
Soon to be putting a Sirio 2016 on top of the pole, quad on the pully so I can remove it and put up other wire antenna projects.
 
Tried it a s.s. whip (102in.) X=0, R= 36...38. but swr 3+. could not get it right... could not make holes in roof so had to use mag mount...not my fav. mount.
got new coax coming from DX eng. and got a Sirio 2016 coming too from dnj or something like that, should be here soon, 3-4 days. And the metal roof plays games with my loop....x=0 but R=134+ swr 3.6 is the best I can get.
I have a metal roof also, I was having 4 to 5 SWR on mine too and couldn't get it down. I was even scared to try and key up to check it, it was so bad. I put a ground on it with a muffler clamp on the lower section of pole with a battery cable over to a ground rod in the ground about 4 feet. My SWR came down to 1.3/1 with nothing else done. oh yea I have a Imax 2000 antenna
 

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