Loops, coax vs solid metal

[jimbooregon]

Hi all,
I'm debating which Wellbrook loop to get. One option is using coax for the loop which can be 3-5 meters and is portable when taken apart; also by using the larger length one gets more capture area. The other option is the aluminum 1 meter diameter loop. It will mainly be fixed/home loop, but portability is intriguing.
I read that coax loops have more resistance, thus less efficient compared to all metal. Would you hear weak signal/DX better with the aluminum??? Any suggestions or ideas welcome.
Thanks
73
Jim

 

[prcguy]

For most receiving loops I'm told the loop resistance and input to the preamp is in the 150 to 250 ohm range from VLF through HF, so resistance of the conductor is of little concern. On a magnetic transmitting loop where the loop impedance is a fraction of an ohm its very important to use a large low resistance conductor.

Have you looked at the W6LVP loops? I have two and am very happy with them and they cost less than the other two big names.

Hi all,
I'm debating which Wellbrook loop to get. One option is using coax for the loop which can be 3-5 meters and is portable when taken apart; also by using the larger length one gets more capture area. The other option is the aluminum 1 meter diameter loop. It will mainly be fixed/home loop, but portability is intriguing.
I read that coax loops have more resistance, thus less efficient compared to all metal. Would you hear weak signal/DX better with the aluminum??? Any suggestions or ideas welcome.
Thanks
73
Jim

 

[ka3jjz]

Here are the product reviews on eHam - 4.9 out of 5...

https://www.eham.net/reviews/view-product?id=13215

Mike

 

[jimbooregon]

Thanks for clarifying the resistance issue.
I'm moving to Scotland from Jordan, so it's cheaper to get the UK Wellbrook.

 

[jwt873]

Which Wellbrook are you considering?

Looking at their site, I see that the only unit they have that accepts a coax loop is the FLX1530LN. There's another one that accepts a solid aluminum tube loop. It's designated as the ALA1530LN. Both use the same amplifier.

The coax version is described as being flexible. The advantage is that you can fold up the coax to make it more portable. The aluminum tube version is more suited for permanent installations.

With the aluminum loop version, Wellbrook supplies the loop. (They charge £66 more for this). With the coax version, you supply the coax and construct the loop.

Apart from one version being more portable than the other, I can't see there being much difference in performance, even if the loop resistance is slightly different. Best bet would be to get in touch with Wellbrook. (Go down to the bottom of their web page and click on "Contact Us"). I'm assuming that they have done field tests comparing the coax and the aluminum tube versions of the 1530LN and can provide a definite answer.

I have the ALA100LN medium aperture loop. I've asked them a couple of technical questions in the past and I've always received prompt replies.

 

[devicelab]

I use the ALA100LN with a 60m 14ga flexweave wire loop and it's terrific. I also have the 1m loop but rarely use it any longer.

 

[jwt873]

60 meters..... That's about 200 feet!! What type of frame do you use to hold the loop?

I'm using a 10 meter (34 foot) square loop made of solid core 14 ga wire. I've been thinking of going larger, but I eventually want to mount it on a rotor and rotate it to take advantage of the nulls so I can't go too big.

 

[devicelab]

60 meters..... That's about 200 feet!! What type of frame do you use to hold the loop?

Who says you need a frame?

I'm using a pseudo-Delta Loop design (triangular shape) -- I use a fiberglass mast to get the apex up about 35ft and the ends flank down from there.

 

[jwt873]

Interesting.. I have a tree that I can use.. Might try a monster loop. Thanks

 

[devicelab]

Interesting.. I have a tree that I can use.. Might try a monster loop. Thanks

I compared it to the 1m Wellbrook and it wasn't a contest. So there's definitely an improvement. Your SNR may rise (of course) but even in my high-RF area it's incredibly effective.