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Posted: 7/26/2013 7:18:06 AM EST
What antennas are you all running for the longer bands? Running the numbers I just do not have enough space for a 260' half wave dipole and a quarter wave vertical also seems ridiculous. I'm assuming you can electrically shorten using coils, but I haven't found anything that I think would work in the space I have available. Am I just doomed to not have these bands until I get a bigger lot or is there something I'm missing?
Link Posted: 7/26/2013 7:29:21 AM EST
I use an inverted vee on 80 with the legs at 90 degrees to each other as seen from above. The feed point is at 32 feet. It fits in a box that's 50 feet on each side, not bad for a full size 80 meter antenna. With a small amp I get consistent unsolicited reports about strong signal strength.

Mine is a fan dipole with another element for 40 meters, you could do the same for 160 & 80.
Link Posted: 7/26/2013 7:44:53 AM EST
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Originally Posted By HarryStone:
I use an inverted vee on 80 with the legs at 90 degrees to each other as seen from above. The feed point is at 32 feet. It fits in a box that's 50 feet on each side, not bad for a full size 80 meter antenna. With a small amp I get consistent unsolicited reports about strong signal strength.

Mine is a fan dipole with another element for 40 meters, you could do the same for 160 & 80.
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How does having the legs 90 degrees to each other affect the azimuth radiation pattern? Is it still broadside or do you get more of an omni-directional pattern?
Link Posted: 7/26/2013 7:50:23 AM EST
I use an inverted-V on 80 and the legs form a 90 deg angle. The apex is only up 25' and the ends are 8' or less. I've worked all over North America, and even South America, Europe, and Africa with it.

On 160 I use an inverted-L that goes up about 30' and horizontally another 100'. I've worked just as far with this on 160 as I have on 80 with the other antenna. Good radials are needed with antenna too.
Link Posted: 7/26/2013 7:58:23 AM EST
[Last Edit: 7/26/2013 7:59:53 AM EST by HarryStone]
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Originally Posted By Yorknoken:

How does having the legs 90 degrees to each other affect the azimuth radiation pattern? Is it still broadside or do you get more of an omni-directional pattern?
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If I model it, it looks like this, a cloud burner. But at this height it's going to be anyway. It's a monster for NVIS. The pattern is almost perfectly omnidirectional.

Link Posted: 7/26/2013 8:05:16 AM EST
I use a 160m windom 90'x180' with a 4:1 balun. If you can put the "center" higher than the ends you can eat up quite a bit of wire in an inverted V shape. I have also used an inverted L for 160m that works quite well but it requires some long elevated radials. Another option my dad uses a sloper. I get out further than he does but he does ok with it.

My Inverted L is the best low band antenna I currently have but expect some trial and error to get things optimized. 160m is a tough DX band and is very addictive. Be careful it can get expensive in a hurry. Did I tell you it's addictive
Link Posted: 7/26/2013 8:36:00 AM EST
[Last Edit: 7/26/2013 8:37:22 AM EST by Gamma762]
Horizontal polarization is not very effective for 160m, verticals will give you better performance.

80 depends on how far away you want to talk. Practical height dipole for short range, or a vertical (with good ground plane) for DX.
Link Posted: 7/26/2013 8:38:16 AM EST
I did have a 40 meter dipole at 12 feet over the pool house. It took me a little over a month and a half to work all 50 states. I know have a inverted V at about 50 feet for 40 meters. I've worked 42 states in about 20 hours of operation over about 10 days in July. I think its still omnidirectional to a point because the legs on the low side are still under a quarter wave. I get a lot of 59 and over reports in all directions. I also have a 20 meter wires set 180 degrees to the 40 meter. Its over a quarter wave high I never hear close states.


On 20 I still need my state and the ones touching it except MO which I got on ground wave. I need something with a higher take off angle on 20 to help work in closer I think. Any one have a suggestion ?

I'm going to build a inverted V for 80. I think I can get it up about 60-65 feet at the top. I had been using my 40 dipole tuned up with the tuner over coax. Probably lucky to be putting out 25 watts. I still have QSL cards from about 15 states. I like 80 because I got a card from everyone I talked to.

For 160 I have a bunch some scrap wire. I was going to put it together to get a half wave dipole and zip tie it to the top rail of my pvc fence and see how it would work NVIS

I have seen a loaded vertical for 160 in QST. They guy who built it and has worked all 50 and quite a bit DX with it.
Link Posted: 7/26/2013 8:58:14 AM EST
I wouldn't mess around with dipoles and inverted Vs on the low bands. Short verticals (less than 1/4 wave) work great on 80 and 160. You can top load with wires or base load with a coil (or a large toroid). There are plenty of ideas on the web. Check out AD5X's 43' vertical presentation. Also, DJ0IP has a bunch of designs for low band wire antennas using an 18m Spiderbeam pole. Or the K6MM helically wound vertical built with PVC pipe (the "No Excuses Vertical"). Heck, you can even get a Hustler BTV to work on 80 and 160.

Check out ON4UN's book for all the details on short vertical antennas for the low bands. In a nutshell, the pattern of a short vertical is nearly identical to its big brother (the 1/4 wave vertical). The tradeoffs are in efficiency and bandwidth. You can increase efficiency by keeping your losses low (good ground, high Q coils, top loading preferred over base loading).

Bandwidth is the other issue. The 2:1 SWR bandwidth of a short vertical can be 20 kHz or less. Not much of a problem if you operate CW only on Top Band. But it's a bigger issue if you want to use 80m for CW and phone. You can increase usable bandwidth by having a matching network with multiple taps for different parts of the band. Or put an auto tuner at the base of the antenna.

Don't be discouraged! Getting on 80 and 160 is really not that hard. (Being loud in EU on 80 and 160 is another story. As is being able to hear everyone who can hear you. But I digress...)

Good luck with it!

73
Link Posted: 7/26/2013 9:05:06 AM EST
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Originally Posted By gubernator:
I wouldn't mess around with dipoles and inverted Vs on the low bands.
...

The tradeoffs are in efficiency and bandwidth.

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I agree. That's why I use an inverted vee.
Link Posted: 7/26/2013 9:20:36 AM EST
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Originally Posted By HarryStone:


I agree. That's why I use an inverted vee.
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Discussion ForumsJump to Quoted PostQuote History
Originally Posted By HarryStone:
Originally Posted By gubernator:
I wouldn't mess around with dipoles and inverted Vs on the low bands.
...

The tradeoffs are in efficiency and bandwidth.



I agree. That's why I use an inverted vee.


I'd rather run JAs at grayline with my 20 kHz of usable bandwidth on Top Band than listen to a bunch of S9+20 locals check in to the weekly gall bladder net on 75 meters. That's why I use a short vertical.

Different horses for different courses.
Link Posted: 7/26/2013 11:46:47 AM EST
160M G5RV, ugly balun, and 75 ohm LMR-400.
Link Posted: 7/26/2013 1:37:33 PM EST
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Originally Posted By gubernator:


I'd rather run JAs at grayline with my 20 kHz of usable bandwidth on Top Band than listen to a bunch of S9+20 locals check in to the weekly gall bladder net on 75 meters. That's why I use a short vertical.

Different horses for different courses.
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Discussion ForumsJump to Quoted PostQuote History
Originally Posted By gubernator:
Originally Posted By HarryStone:
Originally Posted By gubernator:
I wouldn't mess around with dipoles and inverted Vs on the low bands.
...

The tradeoffs are in efficiency and bandwidth.



I agree. That's why I use an inverted vee.


I'd rather run JAs at grayline with my 20 kHz of usable bandwidth on Top Band than listen to a bunch of S9+20 locals check in to the weekly gall bladder net on 75 meters. That's why I use a short vertical.

Different horses for different courses.



Working JA's on 160m is more fun though
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