Wellbrook ALA1530 vs PAR EF-SWL. Who'll win?

[TassieJay]

Suburbia: A shortwave radio enthusiasts nightmare, what with switch mode power supplies and plasma TVs and cable modems spreading misery across the HF spectrum. Then add a healthy dose of terror if you live in a rental property that has a 'no CB antennae' clause. Welcome to my RF hell for the last three years.

After suffering from radio withdrawal symptoms for so long, I finally decided to do something about it. While my little Degen / Kaito 1103 with a 10 foot indoor longwire running along the curtain rod was OK, it suffered badly at the hands of neighbourhood plasma TVs and swithmode power supplies - cell phone chargers being some of the worst. I got a PAR EF-SWL antenna, and installed it stealthily along the back fence line, optomised the earthing for lowest noise & interference, and buried the coax to come inside. In some cases the EF-SWL was better than the indoor random wire, sometimes not.

Dismayed even after having done everything right with the EF-SWL and still not achieving the desired result, I'd almost given up hope of sinking my teeth into some decent and noise free shortwave listening... when Wellbrook come to the rescue with their active loop the ALA1530. Now things are looking up, as the below video demonstrates. The ALA1530 isn't perfect, it won't completely rid your life of every bit of interference. But in some circumstances, especially at lower frequencies, the ALA1530 was rejecting noise far better than the EF-SWL. And in my testing from 200 kHz to 29 MHz, the ALA1530 always had a 2 to 6 S-point advantage over the EF-SWL which was very suprising. Most importantly though, the ALA1530 without exception produced a signal that was as listenable or better than that delivered by the EF-SWL.

As I play with the Wellbrook, learning its limitations and advantages, I'm liking it more and more. No, it's not perfect, but then what in life is? But it is very very good, and perfect for those who live in the urban jungle looking for a quiet or stealthy antenna.

Wellbrook ALA1530 vs PAR EF SWL 160mtrs with plasma TV interference - YouTube

 

[SCPD]

Yep there's no contest between the Wellbrook and a wire antenna. I'm sure there are some specific scenarios where a wire antenna would be best (i.e. a true beverage antenna for LW or MW) but for general SWL the 1530 is hard to beat.

 

[brandon]

Yep I have compared both and concur with your findings PAR EF SWL and Wellbrook perform around the same from 8 to 12 MHz, but once you get into the lower bands the Wellbrook loop wins hands down. It hears stuff down there the wire would not even dream of.

Use that PAR EF-SWL for a noise pickup antenna for a MFJ-1026 or Timewave ANC-4 to complete rid that Plasma TV and phone charger QRM.

Examples (switched off/on)
Cancelling iPhone charger noise
http://solarix.org/audio/noise_cancelling.mp3
http://solarix.org/audio/noise_cancelling2.mp3

Cancelling Plasma TV noise
http://solarix.org/audio/plasma_noise_cancel.mp3

 

[zl2taw]

good stuff Jay, gotta love the loop

sorry to hijack the thread, but how much QRM to cell phone chargers cause ?
How close do they have to be ?


great stuff Brandon

 

[nanZor]

I hope you are rotating the loop to try and put the plasma tv into a null. You may find that rotating the loop is necessary when moving from one end of the band to the other, depending on what other noise sources are out there.

Unless you are very lucky, having a small loop in a fixed permanent position isn't making the most use out of it's low-angle directional nulling capability, so a rotator or nearby strong-arm method is used.

Years back I lived in a two-story house and the loop was upstairs. The only way to null the TV from downstairs was to tilt the loop, as well as rotating it. That tilt nulled out the noise, BUT the loop was no longer as receptive to high-angle arriving signals as it could be.

Lesson learned was that sometimes, having a loop up higher than your noise source may make it harder to null without tilting it - so a lower mount for the loop so the null can be obtained without a tilt could be an advantage.

 

[ab3a]

I have several points to make:

First, this is not a situation where one solution is always better than another. The loop is good for some stuff, the isolated random wire is good for others.

Second, a lot of noise creeps in via poorly balanced antenna and transmission line systems. A loop such as the Wellbrook tends to be very balanced, so the opportunity for noise to creep in is significantly less. Years ago, QST had an article for an active VLF antenna. It was a vertical. This surprised me until I realized that it was very carefully decoupled from the surrounding noises. I built it and discovered that it was indeed "quieter."

Third, yes, switching supplies and TV (remember those old flyback transformer noises every 15 kHz? ) are the bane of shortwave listeners and they have been for a long time. The solution is to get your antenna out of the house and up, above it all. If you can't do that, at least consider electrostatic shielding.

None of this is cheap. So in the scheme of things, consider the loop antenna as a good place to start.

Finally, I have noticed that people are getting more and more hostile to anything in a neighborhood that might be perceived as a blight amongst their perfectly manicured show homes (note the dripping sarcasm here). If you can't put up much of a station at home, don't overlook the notion of establishing a community center station of some sort. No, it's not quite the same as listening with a cold one in your hand at home. But the camaraderie and helpful crowd could very well make up for it.

 

[SCPD]

First, this is not a situation where one solution is always better than another. The loop is good for some stuff, the isolated random wire is good for others.

I respectfully disagree. With the exception to a beverage antenna (which is not practical for 99.8% of SWL'ers) the Wellbrook 1530/330 models will blow wire antennas out of the water.

 

[ridgescan]

You tell em Nick nasty old dumb wire antennas..

 

[pb_lonny]

Good looking video, really shows the advantages of them.

 

[ab3a]

I respectfully disagree. With the exception to a beverage antenna (which is not practical for 99.8% of SWL'ers) the Wellbrook 1530/330 models will blow wire antennas out of the water.

Nick, I built K0BRA's active vertical antenna design for LW.

It works REALLY well.

That said, I did point out that an active loop is a good start.

As for wire antennas, if you isolate them or use a balanced system and feed, they can perform surprisingly well. Of course, I live in a mostly rural area, so YMMV.

 

[ridgescan]

Nick, I built K0BRA's active vertical antenna design for LW.

It works REALLY well.

That said, I did point out that an active loop is a good start.

As for wire antennas, if you isolate them or use a balanced system and feed, they can perform surprisingly well. Of course, I live in a mostly rural area, so YMMV.

+1 and I live in a RFI nightmare like brandon. But that PAR with two good groundpoints-one right at the antenna, and one down here at the antenna switch, makes the bands way way quieter, but not near as quiet as a loop I know. With the 100' wire, it sort of makes up for it by giving bigger signals. I do need to get a loop up there too though. Honestly, been going the cheap route lately.

 

[7designs]

With the Wellbrook ALA-1530 having a of MSRP: $200 £ + charge, I would have to say my free(had wire) long wire has a HUGE advantage!

 

[SCPD]

With the Wellbrook ALA-1530 having a of MSRP: $200 £ + charge, I would have to say my free(had wire) long wire has a HUGE advantage!

You forgot to add the last few words to your comment:

"...HUGE advantage to me."

If the antenna was not important then HAMs (or SWL'ers) would use wire antennas instead of spending THOUSANDS of dollars on towers, hardline and massive directional YAGIs or LP antennas.

So it's all relative to YOUR budget -- as with most things in life. At times though, people want performance versus cost and are willing to pay insane amounts of money for this extra edge.

So you see, $400 is not that much for a small, compact antenna that can be better or equivalent to a wire antenna -- and is perceptibly less noisy than a wire antenna.

 

[7designs]

You forgot to add the last few words to your comment:

"...HUGE advantage to me."

If the antenna was not important then HAMs (or SWL'ers) would use wire antennas instead of spending THOUSANDS of dollars on towers, hardline and massive directional YAGIs or LP antennas.

So it's all relative to YOUR budget -- as with most things in life. At times though, people want performance versus cost and are willing to pay insane amounts of money for this extra edge.

So you see, $400 is not that much for a small, compact antenna that can be better or equivalent to a wire antenna -- and is perceptibly less noisy than a wire antenna.

You are exactly right! I normally take everything posted online as opinion.

I would love to have a wellbrook, just can't afford it. Any money for this hobby is spent on Ham gear and not swl. But I love firing up my one of my old Hallicrafters and turn that dial.

 

[zl2taw]

If I didnt grab a Wellbrook, the hobby I enjoy so much would have ended back in the cupboard for another 20 years.
Now everyone has to put up with & my questions

 

[SCPD]

If I didnt grab a Wellbrook, the hobby I enjoy so much would have ended back in the cupboard for another 20 years.
Now everyone has to put up with & my questions

Initially this wasn't the case for me but lately (with all of the new electronic devices) and "cheap" plasma TVs that are selling for $200 ... the RFI levels have sky-rocketed in the last year.

So yes the RFI prevention can be a definite benefit. I was shocked at how much better my SnR was with the loop.

The 1530 S+ == modest signal + exc noise = perceived great performance

The 300ft random wire, un-un and coax fed = exc signal + poor noise = perceived avg performance

(And if you do have noise on the 1530 then you can possibly rotate it and null out the high noise.)

 

[brandon]

Yep same here Nick. The past month or so I've had many new RFI sources pop up. I have been forced to get out of the HF radio hobby because it's just too much bull**** to put up with now.

When I first moved here, I could use a PAR SWL wire antenna and hear stuff with now noise. Now you hook up the wire and it's all noise. The loop makes things manageable and I do not get that type of buzzing RFI as much. But the loop still cannot prevent the Plasma TVs, air purifiers and other crap that has popped up.

Here is what 5 MHz used to look like for me during most evenings/nights. (image) -- Now 2 months later here is where we stand: (image) --- Much worse!! And here is what 4 megs looked like 2 months ago (image)

Up on 6 MHz things get even worse!!! (image)

 

[SCPD]

Yep it's very odd recently. I use to have issues with 3/4 meg bands and now those are fine. Now it's mainly 6 thru 7 meg bands that suck -- which is where a lot of fun signals are...

Just out of curiosity, are you seeing RFI with both SDRs or just the new one? I wonder if the newer SDR is picking up USB and/or external noise?

I'm starting to wonder if all of these new LTE towers (that are stuck in residential neighborhoods) are creating this RFI...?

 

[Turbo68]

Hi Brandon recently i put a Yaesu-G250 rotator on my Wellbrook-ALA1530AL-1 and can see the benefits of nulling out interference from plasma tv..

Regards Lino..

 

[nanZor]

When I first moved here, I could use a PAR SWL wire antenna and hear stuff with now noise. Now you hook up the wire and it's all noise. The loop makes things manageable and I do not get that type of buzzing RFI as much. But the loop still cannot prevent the Plasma TVs, air purifiers and other crap that has popped up.

Don't get out of the hobby - go to war (so to speak). I feel for you since two of my neighbors went BPL and rendered my small loop useless on nulls.

Nick hit it on the head that when confronted with a massive noise problem, improving the SNR and not pegging the S-meter is key. Small loops obviously rock, and don't even need to be mounted high above ground, but they can be defeated by wide non-specific noise transmitters without a tight localized source.

I may have mentioned it before, but don't discount using a small vertical that can "hide" in between the forest of mostly vertical noise sources when the loops are defeated. Go on the hunt with a portable (ssb preferably) with the telescopic straight up, and try to find that relatively noise free area and plant a vertical there. Check all the bands of interest. This may be easier than it sounds, where only two or three feet either way on your property may put you into a noise field. But once found, you are back in the hobby - especially so if you are using a modern sensitive tabletop communications receiver as opposed to a portable.

Yeah yeah, everyone likes to paint the verticals with a broad brushstroke of being somehow noisy in and of themselves, when for the most part, many are just prone to unchoked common mode on the coax feedline, or placed near an induction field of noise to begin with. Plant your vertical with some care and you may be surprised.

The one thing you can't overlook is that you have to choke the crap out of the feedline at the feedpoint, so the coax isn't really part of the antenna. Ugly-balun, ferrites, whatever it takes to isolate the common mode. Long radials? Consider elevating them a foot or so if you can do so safely, and load them to make them shorter, or just fold them back upon themselves if you have to. It may not be perfect, but as long as one keeps in mind the SNR benefit of finding a quiet vertical "hole", this imperfection can be tolerated - at least on receive.

An example is for my amateur monitoring duties, I've got a triple-tree setup of get this: Hustler mobile verticals - INDOORS (near a huge expanse of windows), with folded radials - actually a single symetrical FCP "folded counterpoise" radial that runs near the walls but slightly elevated. Oh, my single-story house is covered with a steel roof! But with a vertical, I'm not looking for high-angle reception above my house. Yet things are good - not as good as an outdoor location free of noise, but rest assured I'm not going to waste time on dummy loads or antennas that are directional upwards to my steel roof and not out the glass instead. The hustlers are narrow in bandwidth, so I don't usually recommend them for swl / util duties.

I'm also not grounded to the noisy house ac. I'm running from an Optima YellowTop AGM battery and using a Schumacher 10-amp charger with agm-charging capabilities - never unattended or while sleeping! The whole system is floating with the indoor antenna, although I do have a 300 megohm resistor across the feedpoint for a bit of static discharge protection.

One possible vertical option for SWL usage 7mhz or so and up would be the portable MP-1 super-antenna with it's continuously variable coil. Just an example, a good tuner to a top-loaded T only 8 feet tall could do wonders - as long as one went on the hunt to find the noise-free hole to plant it in. Indoors, outdoors, on the deck etc - many options here.

I guess the point of my rant is that don't overlook short verticals - they can work if done right, and your goal is not to peg the s-meter, but go for SNR instead. But don't take my word for it - grab a portable and go on the hunt! You might feel like you are in a paintball contest as you hunt for it, but when you find it, you'll be grinning ear to ear.