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K9FON
10-15-2009, 09:45 PM
i am thinking of putting up a 160 meter antenna here at my folkses since i moved back home. The lot is shaped like a big L with one leg going south and the other east.
I know id have room for the south leg but, the east leg would have to be folded back to a 90 degree angle or steeper. How would this affect the tuning on the antenna?

N8YX
10-16-2009, 07:09 AM
i am thinking of putting up a 160 meter antenna here at my folkses since i moved back home. The lot is shaped like a big L with one leg going south and the other east.
I know id have room for the south leg but, the east leg would have to be folded back to a 90 degree angle or steeper. How would this affect the tuning on the antenna?
Folded, you say?

How about a folded dipole fed with a 4:1 balun and coax?

You should be able to get such an arrangement in the air in ~125 linear feet.

K9FON
10-16-2009, 01:46 PM
Speaking of folded dipoles has anyone had any exp. with the B&W folded dipoles?
They look like the way to go, but i have heard some hams having problems with the termination resistor burning out with power. I run over 1200 watts so that might be an issue.

N8YX
10-16-2009, 03:20 PM
Speaking of folded dipoles has anyone had any exp. with the B&W folded dipoles?
They look like the way to go, but i have heard some hams having problems with the termination resistor burning out with power. I run over 1200 watts so that might be an issue.
I would look into shortening a folded dipole by means of a couple of loading coils placed in the bottom two "legs", equidistant from the feed point and the end supports.

The 'T2FD' design is not favorable for high power unless you can get your hands on some high-wattage, non inductive resistors. That might be a bit hard to do.

You could even shorten a regular dipole with a pair of loading coils, and if you choose the "inside" lengths wisely you'll have a multiband antenna to boot.

Look at Alpha-Delta's "DX-LB" series of dipoles. 160-80-40 in a 100' overall length package. This would be doable in your situation, and could be easily duplicated by the amateur constructor. If you need extra bandwidth, you could always get clever with a pair of vacuum relays at the ends of the thing and switch in an extra foot or two of wire:

http://www.alphadeltacom.com/images/Image32.gif

K9FON
10-16-2009, 06:57 PM
Ya know, I have a 20 40 80 and 160 meter trap dipole at my old house, but my ex has it now and getting that back is subject to question!!!!!!!
Spi-Ro has a set of 160 meter antenna shorteners that might work. But i dont know what the power handling capabilities are.

K9FON

W4GPL
10-16-2009, 07:01 PM
http://www.qsl.net/aa3px/invl.htm

My friend has an "Inverted L" that works pretty good...

ad4mg
10-17-2009, 06:51 AM
Speaking of folded dipoles has anyone had any exp. with the B&W folded dipoles?
They look like the way to go, but i have heard some hams having problems with the termination resistor burning out with power. I run over 1200 watts so that might be an issue.
I had a B&W 10-80 meter folded dipole up some time ago. I didn't run any significant power into it. My experience was that it was nice and quiet on receive, and a decent performer on the higher bands. The performance on 40 meters, and especially 75/80 meters, left a bit to be desired.

Mine was mounted as a flat-top, up about 55', in a nice clear area. I replaced it with a dipole cut for 80 meters, and fed with 450 ohm ladder line. The difference in performance was incredible, with the dipole winning hands down.

No help for your antenna question, but I hope you find the info on the B&W useful!

W9WLS
10-17-2009, 07:31 AM
The B&W is a re-make of the "T2FD" which is a shortened terminated "LOOP" antenna.
"LOOP" antennas are usually quieter than dipole's unless you live in a "HIGH NOISE" area.
There was an article on winding a 160 vertical in qst a couple of months ago that looked interesting , but I haven't tried it as yet , might work out good for you on a small lot though.

73, John

N1LAF
10-20-2009, 09:06 PM
Speaking of folded dipoles has anyone had any exp. with the B&W folded dipoles?
They look like the way to go, but i have heard some hams having problems with the termination resistor burning out with power. I run over 1200 watts so that might be an issue.
I had a B&W 10-80 meter folded dipole up some time ago. I didn't run any significant power into it. My experience was that it was nice and quiet on receive, and a decent performer on the higher bands. The performance on 40 meters, and especially 75/80 meters, left a bit to be desired.

Mine was mounted as a flat-top, up about 55', in a nice clear area. I replaced it with a dipole cut for 80 meters, and fed with 450 ohm ladder line. The difference in performance was incredible, with the dipole winning hands down.

No help for your antenna question, but I hope you find the info on the B&W useful!

Same here, except I had the 6-160 M folded [strike:19wdb9o2]dummy load[/strike:19wdb9o2] dipole. Very quiet on the receive, but lackluster transmit performer. I replaced it with a full 160 meter/273 foot dipole with 450 ohm windowed ladder line (stranded). The dipole is a better performer.

n2ize
10-23-2009, 06:20 PM
Use an 80 meter doublet fed with balanced line. Tie the ends of the balanced line together and work it against a good ground. Won't be the greatest but will steill get you out on 160.

K9FON
10-25-2009, 09:33 PM
well il just going to put up a regular "plain vanilla" 1/2 wave dipole. It was a nice day outside today so I measured the lot and i will have plenty of room for the ends.
I have a friend that is trying to talk me into getting one of those goofy looking Bilal Isotron antennas. I have heard they are junk and dont work that well, but i see them all the time being sold at the hamfests. :-|

N8YX
10-25-2009, 09:42 PM
well il just going to put up a regular "plain vanilla" 1/2 wave dipole. It was a nice day outside today so I measured the lot and i will have plenty of room for the ends.
I have a friend that is trying to talk me into getting one of those goofy looking Bilal Isotron antennas. I have heard they are junk and dont work that well, but i see them all the time being sold at the hamfests. :-|
In a word: Don't.

Most of their radiation is off the feedline. Even a shortened, loaded dipole is going to be better - especially on 160.

John gave you a good suggestion - configure an 80M doublet as a Marconi and feed it with a tuner. Make sure to lay down a decent counterpoise, though.

K9FON
10-26-2009, 12:48 PM
Well i guess there is market for amything then. I just dont see how those Isotrons work all that well. But guys buy them and use them. I actually worked a guy on 75 the other ngith that was using an Isotron and he gave me a decent 5/7 signal. Granted he wanst that strong like someone on a dipole but he sounded ok. I was shocked to know that he was using an isotron. I have the room here so i can just put up a regular dipole.

kq9j
10-28-2009, 05:54 PM
I have had a full-size 160 meter dipole up on my small lot for years. The first half of each element comes down from the tower like a normal inverted vee, then the rest of each element is bent and folded back and everything possible just to get it to fit on the lot. Maybe making some loading coils and shortening the elements would pretty it up a bit, but it works so dang good I don't want to mess with it.

N9FE
10-29-2009, 09:31 AM
Use an 80 meter doublet fed with balanced line. Tie the ends of the balanced line together and work it against a good ground. Won't be the greatest but will steill get you out on 160.
This is what i do.. It does work..

w3bny
01-25-2010, 02:00 PM
Look at Alpha-Delta's "DX-LB" series of dipoles. 160-80-40 in a 100' overall length package. This would be doable in your situation, and could be easily duplicated by the amateur constructor. If you need extra bandwidth, you could always get clever with a pair of vacuum relays at the ends of the thing and switch in an extra foot or two of wire:

http://www.alphadeltacom.com/images/Image32.gif


Ive owned one of the DX-LB+ antennas. Not bad. Once you see it you will be kinda upset on tossing money for it. But I looked at it like I was buying the coils. The fan wires are incidental. It worked.. It loaded up 160 and I made contacts. Better than no antenna on the lot!

PA5COR
01-25-2010, 02:26 PM
The plot of land here is just 100 feet by 25 feet :roll:

With the use of the houses nearby i put up a FD-4 OCF, lengthened it on the short end with a coil and 30 feet of wire to make it resonant on 160 m.
Total length of the OCF is now 55 meters, or 185 feet, at 13 meters above ground, or 45 feet.
The rest of the bands were not effected, so now the OCF works as shortened dipole for 160 and 1/2 wave for 80 etc.
Next was the vertical, ( there is always room to go up) 45 feet of 1 1/2 inch glass fiber mast, helically wound 1/10 inch alu wire and now 2 x 12 meters ( 40 feet) wire as T antenna over 1400 feet copper wire in the ground.
As just helically wound vertical iit worked just fine, the ground here is quite good young sea clay very moist.
The ground radials are just 2 inches deep in the ground, covering my patch and some outside it.

Te vertical is 45 feet high, on it now approximately 120 feet of the alu wire, and the 2 x 12 meters top capacity.

SWR 1:1 on 1850, but thanks too the top hat quite workable over a larger part of the band, 1810 to 2000 within 1:3.
I set mine to 1850, where i work the most, so if you make the center of your 160 meter band resonant it would cover 1810 to 2000 KHz within 1:2 SWR.

That is what my MFJ 269 analizer told me ;)

I run the coax directly to the vertical, just a !:1 balun at the feed point, and 800 watts in it without any problem in the city here.
( SB 1000) and it is just used as monobander for 160 meters.

Some pictures are here in the antenna section.

73,
Cor

kf4jqd
04-25-2010, 08:53 AM
I have a doublet antenna that is cut for 75m, but fed with 450 ladder line. It works well on 160m! Side note: If you can put up any 75 dipole antenna. Replace the coax with 450 ladder line. You now have antenna that works 10-160!

Andy