Meandored full wave loop

[xm49north7]

As some of you know I am crazy about loop antennas, here is this weeks project a meandered full wave loop, about 3 feet wide by 4 feet tall, will begin tuning this for swr over then next few days see if it will work or not.

 

[Shadetree Mechanic]

Interesting, is it like a one element quad?

 

[xm49north7]

Interesting, is it like a one element quad?

Yes I currently have 2 single full wave loops on the roof, they work very well for me, and have been great for dx so far, so this was me trying to condense it down , my full loops are about 6 feet wide by 12 feet tall, this mini loop is about 3 feet wide by 4 feet tall, just had it on a few min. ago, it works, on receive, has high swr of about 3 across the board right now, and has been tunes about as far as it will go, so will need a balun of some sort to get it usable.

 

[BJ radionut]

https://qsl.net/xe1cdx/Hamdocs/10/10 mts Loop.pdf

Increase these lengths by about 4% should make this fall in for SSB on 27.400
About 2db gain over a dipole and a slightly more gain than a standard single square loop (1.7dB over dipole) but lets not get picky

Shrinking the loop to 3 x 4 ft is over 60% below resonate 50 Ohm length...
No simple Balun, I would think will bring that small of length into Transmit range.
Going to need a lot of capacitance to bring that into where it will load I would think.
Adding a Air-Variable cap may bring it into play(much like tuning a Mag-Loop antenna) but the spacing on the plates of the cap unless very wide, will reduce the power that can be used when transmitting.
This is due to the antenna length will barely be 3/8th's wave long overall and a closed loop at that.
Square Quad loop is 1005/27.4 = 36.7 ft overall...close to 110 inches each side.
The size frame your using will only give you roughly 14 ft. overall which is aprox. 62% smaller.

http://www.iw5edi.com/wp-content/uploads/2012/07/pfeiffer-quad-antenna-system-reduced.pdf
Above this maybe another option to look at.

GL Have fun
All the Best
Gary

 

[BJ radionut]

If your seeing a 3:1 VSWR minimum...that means the impendence of the Loop is aprox or greater than 150 Ohms...???

Might bring to 75 Ohms(1.5:1) but that's a guess!
Not knowing the TRUE impedance of the antenna, only a good analyzer will tell you that.

 

[xm49north7]

https://qsl.net/xe1cdx/Hamdocs/10/10 mts Loop.pdf

Increase these lengths by about 4% should make this fall in for SSB on 27.400
About 2db gain over a dipole and a slightly more gain than a standard single square loop (1.7dB over dipole) but lets not get picky

Shrinking the loop to 3 x 4 ft is over 60% below resonate 50 Ohm length...
No simple Balun, I would think will bring that small of length into Transmit range.
Going to need a lot of capacitance to bring that into where it will load I would think.
Adding a Air-Variable cap may bring it into play(much like tuning a Mag-Loop antenna) but the spacing on the plates of the cap unless very wide, will reduce the power that can be used when transmitting.
This is due to the antenna length will barely be 3/8th's wave long overall and a closed loop at that.
Square Quad loop is 1005/27.4 = 36.7 ft overall...close to 110 inches each side.
The size frame your using will only give you roughly 14 ft. overall which is aprox. 62% smaller.

http://www.iw5edi.com/wp-content/uploads/2012/07/pfeiffer-quad-antenna-system-reduced.pdf
Above this maybe another option to look at.

GL Have fun
All the Best
Gary

This small loop has the 36.5 feet of wire, it has just had the top and bottom meandered to take up less space, I currently have an swr of 3 across the board, I think a 4;1 balun will take care of this, if not no big deal, that is why I am doing this to find out. Just shop scrap. My full wave loops work really well, I am hoping to get a 4 element quad loop beam up in the fall. The maltese looks like a great idea!!!