End fed antenna propagation direction

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[ARCHIVED THREAD] - End fed antenna propagation direction

Posted: 5/1/2015 9:36:20 AM EDT

Which way does it work? I am going to a cabin this weekend with a yet to be constructed end fed sloper with a 9:1 Balun Designs balun. Does it go broadside like a dipole, off the higher end? Any other tips, thoughts, etc always welcome.

Posted: 5/1/2015 10:09:16 AM EDT

[#1]

EndFedz states that a sloper will be directional toward the bottom of the antenna.

3.A sloper, as you might guess, is in between a horizontal and a vertical. It can have another advantage though in that it will be somewhat directional- towards the direction of the bottom of the antenna. If the high end is East and the low end West, the sloper will have perhaps 3dBd of gain to the west and a front to back ratio of 7-8dB. This can be an advantage if you essentially wish to work one direction, and attenuate signals from the opposite direction.

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Taken from: http://www.lnrprecision.com/tech-notes/

I almost always install mine as a sloper and never really notice much of a difference in directionality...but then I've never really moved around in the same spot and changed the direction of the antenna for a given deployment.

Posted: 5/1/2015 10:09:16 AM EDT

[#2]

My (home mounted) LNR EndFedz is also a sloper, oriented N to S, sloping up to the south. I seem to have more broadside contacts to the E and W. Like Raysheen, I don't ever move mine from it's home position, so I can't say if it does better for sure sloping a different direction.

Posted: 5/1/2015 10:12:39 AM EDT

[#3]

For me...deployment is all based on available tree branches...never tried to get directionality.

Someone here has mentioned using radials with an endfed...I would expect that to increase gain in the direction of the radial.

For SOTA, I really don't want directionality.

Posted: 5/1/2015 10:42:57 AM EDT

[#4]

Thanks to all for the replies! I'll throw it up with the low end pointing either NW or WSW and see what happens. Makes the coax run easier.

For you SOTA fanatics - what kind of battery would you recommend for an IC-706? I have a summit not far away that is a very short (100 yards) hike and 2,000 ft or more above local terrain. I have a 12V boost box if that would work for a short period of time....Yeah, yeah, throwing it together at the last minute

- that's part of the fun! I'm not sure I'l have time though.

Posted: 5/1/2015 11:45:25 AM EDT

[#5]

As with any antenna, it depends on the wavelength of the antenna. "Antenna" including whatever counterpoise is present.

If the fed wire (half of the "antenna") is 5/8 wavelength or less, maximum signal is broadside to the element. As wavelength goes up, signal pattern skews to an "X" shape, with the signal lobes getting closer to the axis of the antenna as wavelength increases.

Posted: 5/1/2015 11:52:12 AM EDT

[#6]

I use Lipo batteries as they are small for their power. I get about an hour at full power on my 857D per pair.

You do need to be careful of the voltage though, they are 8.4V fully charged, so 16.8V! I made a voltage dropping device for when I first start operating out of some power regulating diodes. There's a thread here with a much fancier device schematic listed/linked.

Several really good SOTA threads here end of last year, search the archives.

Any battery that supplies the right voltage and can handle your operating current draw will work. Need to know the amp-hours to figure out for how long.

Posted: 5/1/2015 1:10:01 PM EDT

[#7]

Quote History

Quoted:

I use Lipo batteries as they are small for their power. I get about an hour at full power on my 857D per pair.

You do need to be careful of the voltage though, they are 8.4V fully charged, so 16.8V!

View Quote

8.4 is two cells in series. Three in series would be 12.6 when fully charged, so probably more appropriate.

Posted: 5/1/2015 4:49:09 PM EDT

[#8]

Quote History

Quoted:

8.4 is two cells in series. Three in series would be 12.6 when fully charged, so probably more appropriate.

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Quote History

Quoted:

Quoted:

I use Lipo batteries as they are small for their power. I get about an hour at full power on my 857D per pair.

You do need to be careful of the voltage though, they are 8.4V fully charged, so 16.8V!

8.4 is two cells in series. Three in series would be 12.6 when fully charged, so probably more appropriate.

Yes, if and when these give out I will go that route.

Posted: 5/1/2015 8:36:20 PM EDT

[#9]

In the real world with ground losses, the directivity is only a couple of dB, about an S-unit or so.

Posted: 5/2/2015 10:28:25 PM EDT

[#10]

Propagation is normally broadside like a dipole, you can alter it with radials but it's generally not worth it...

Posted: 5/3/2015 8:30:21 PM EDT

[#11]

Quote History

Quoted:
Thanks to all for the replies! I'll throw it up with the low end pointing either NW or WSW and see what happens. Makes the coax run easier.

For you SOTA fanatics - what kind of battery would you recommend for an IC-706? I have a summit not far away that is a very short (100 yards) hike and 2,000 ft or more above local terrain. I have a 12V boost box if that would work for a short period of time....Yeah, yeah, throwing it together at the last minute

- that's part of the fun! I'm not sure I'l have time though.

View Quote

I use a 12 AH SLA battery with my FT-857D. It's cheap, relatively safe and lasts all day, with moderate TX duty cycle at 25-30Watts. My QRP setup (FT-817 and KX3) has two 5AH SLA batteries. One battery usually lasts all day while I charge the other one with a 10W solar panel.
The batteries are not the lightest but I don't mind the little extra weight. They are cheap and don't require any fancy charge controllers.

[ARCHIVED THREAD] - End fed antenna propagation direction

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