YouLoop Loop Ant. Question Re Sensitive Axis, etc.

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BOBRR

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Hi Folks,

Hope this isn't considered as a duplicate, but I tried posting first
in the very specific loop antennas group in groups io. Thought that would
be the most appropriate, as it's so specifically oriented for loop antennas. No replies.

Have never used a Loop before, but thought I would have some fun and purchased
the YouLoop from the Airspy folks. Hasn't come yet, but will of course do a lot of experimenting with.

In the meantime, would like to please ask:

I guess this is considered a "small" loop antenna.

As such, my reading up a bit on them, is somewhat confusing, as i don't have a good background
in ant. theory. Is:

a. The "sensitive" axis or axes, is the Plane of the Loop. True ?

b. So this in effect makes it Omni directional. True ?

*c. If so, do I want to orient the loop's Plane horiz. or vert. ? Why ?

I do only listening, AM, usually below 5 MHz or so. Have a SDRPlay RSPdx.

And, just one more, please.

They mention, but are not explicit, that it can also be used for VHF freq's.

d. Anything different in configuring for VHF ?

Same direction for the sensitive axis ? etc. ?

Any caveats, tricks, etc. that would be helpful ?

Thanks, appreciate the help.
Bob

*e.g., Sensitive axes still the plane of the loop ?

Anybody using this, would be most appreciative for hints, thoughts on, etc.

Here's a quick one as I imagine you folks know.
What is the "sensitive" direction for a simple, above the ground, "long wire" receive on ant. ?
Along the wire axis direction, or broadside to it ?

Much thanks, very appreciative for help and comments
 

Arkmood

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Taney County MO
Other members(Token,ka3jjz,prcguy-many more) are better qualified to answer your questions
But if they're not around - I'll give it a go:

a. true
b. true
c. Generally speaking hor. for close signals, ver. for distant
d. 25 to 30mhz vertical (also c. applies/may be reversed dependent upon transmit signal)
quick one. Orientated n/s receives better e/w - apply opposite.
 

ka3jjz

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Bowie, Md.
Yes, a loop is more sensitive along its axis, usually. And yes, it should be vertical. It should show some directional characteristics until you get up around 2 Mhz or so. There, skywave propagation takes over. And the higher you go, more skywave is likely. So it won't be too directional around 5 Mhz, it should still have its low noise capabilities.

Now to your long wire (PLEASE ask different topics in different questions). A plain old inverted L that is long (which I suspect is what you mean here, or something similar to that) will favor different directions depending on several factors; the frequency, how high the long wire is off the ground and how long the antenna (and if it's an inverted L, the feedline plays into this) actually is against the operating frequency. In very general terms, think of a bunch of cloverleafs coming off the sides of the antenna. However as it gets longer (approaching 1 wavelength long at a given frequency), it becomes more directive off its ends.

A true longwire is much too long to put on a typical lot - you need a LOT of space for such a beast.

If you are interested in antenna theory, there are many books by the ARRL and the Radio Society of Great Britain on the subject. In addition, Joe Carr has written several books (including one on loops) that I am told are excellent and should be in your library.

Mike
 
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