Great experience with PAR Electronics EF-SWL

Useful information regarding antennas for SDR products.
NoelC
Posts: 72
Joined: Sun Nov 27, 2016 11:50 pm

Great experience with PAR Electronics EF-SWL

Postby NoelC » Sun Jan 22, 2017 11:50 am

I did some homework before buying the SDRplay RSP1 and landed repeatedly on recommendations for the PAR EndFedZ EF-SWL long wire (45 feet) antenna:

http://www.lnrprecision.com/store/#!/EF ... p/39885474

I mounted the box under the eave at the northwest corner of my house, and ran the wire up and over the tops of several modest sized trees, finally hanging the end with a weight near the top of one of them.

I got 28 feet of great low-loss Davis BuryFlex coax cable (less than 1 dB attenuation per 100 feet at HF frequencies) with connectors pre-installed:

https://www.k1cra.com/ProductDetails.as ... DAVISBFLEX

Finally, I picked up an SO-238 to SMA male adapter from eBay to allow the connection between the coax and the RSP.

This combo really works. It blows the doors off the performance I had been getting from my old Radio Shack SWL receiver hooked to a wire strung around the room. I compared notes with a Ham friend and found I'm actually decoding more JT65 stations than he is, and he's put a fair bit of effort into his antennas. And I'm having no problems picking up VHF and UHF signals. For example, I'm getting good, strong 850 MHz signals from PD and fire departments up to 30 miles away (I'm looking forward to a "scanning" feature in a future SDRuno release).

My advice to all who want a delightful SDRPlay-based SWL experience:

Take the time to get a good antenna and mount it outside, away from the noise sources in your home, and get good coax with good quality connectors to bring the signals in. Plan to spend as much on the supporting hardware as on the radio spectrum processor itself.

-Noel

Reason: No reason

CaptainNemo
Posts: 125
Joined: Mon Jan 05, 2015 1:22 pm
Location: Genoa - Italy

Re: Great experience with PAR Electronics EF-SWL

Postby CaptainNemo » Wed May 24, 2017 6:16 am

Hi NoelC, hi all.

LNRPrecision say it is a 1-30 MHz rx antenna.
Anyone can post some performance figures of such antenna vs frequency range?
I mean, this is a "short" wire (about 12 m), it performs the same at 10MHz and at 1MHz? I dont think so.
I have some experience in DIY random wire antenna, and I know every piece of wire can work -- more or less -- as receiving antenna. But you do not have the same "satisfaction" on all bands, especially when you approach the lower bands...

Any kind of figures -- official sheet or personal experience -- in any arbitrary unit of measure will be appreciated.

Thank you.

Reason: No reason

DanubeBCL
Posts: 179
Joined: Sat Jul 02, 2016 12:39 pm

Re: Great experience with PAR Electronics EF-SWL

Postby DanubeBCL » Wed May 24, 2017 2:38 pm

CaptainNemo wrote:LNRPrecision say it is a 1-30 MHz rx antenna.
Anyone can post some performance figures of such antenna vs frequency range?
I mean, this is a "short" wire (about 12 m), it performs the same at 10MHz and at 1MHz? I dont think so.
I have some experience in DIY random wire antenna, and I know every piece of wire can work -- more or less --
Believe in your own experience. You have seen by yourselves what random wires with a 9:1 transformer can do and what they cannot do. Nobody can do miracles howsoever enthusiastic the "reviews" may be.
73, Heinrich

Reason: No reason

CaptainNemo
Posts: 125
Joined: Mon Jan 05, 2015 1:22 pm
Location: Genoa - Italy

Re: Great experience with PAR Electronics EF-SWL

Postby CaptainNemo » Thu May 25, 2017 1:41 pm

;)
Hi Heinrich, hi all.
Perfectly agree with you: I believe in my experience and I believe in sharing info from guy I can trust...
Once someone used to say: "It was told by television"... now the mantra is "It was told by twitter, facebook, google..."
The problem is still the same.

I' m exploring all the spectrum and now I'm particularly interested in coastal radio
(I must hurry up, before they all shut down...).
Let say 1.5 to 2.5 Mhz... what kind of antenna do you suggest?

Bye,
gio

Reason: No reason

DanubeBCL
Posts: 179
Joined: Sat Jul 02, 2016 12:39 pm

Re: Great experience with PAR Electronics EF-SWL

Postby DanubeBCL » Thu May 25, 2017 4:43 pm

Hi,
as someone said: "Even a wet spagetti in the antenna socket is working from 0.01 Hz to 50 GHz. You just have to define what "working" is."
Maybe for your purpose an EWE could be a choice. It does not necessarily take much room. It is directional and you might have to invest some additional circuits for switching the directions. (I myself do not have one, the high local noise does not make it worth while building more antennas). Or something like a K9AY.
And if you have a big garden ;-): Eight beverages of 600 metres length each will certainly bring good results (hihi).
73, Heinrich

Reason: No reason

g1hbe
Posts: 228
Joined: Sat Jan 17, 2015 3:28 pm
Location: Cheshire

Re: Great experience with PAR Electronics EF-SWL

Postby g1hbe » Thu May 25, 2017 6:19 pm

Hi Captain.
Wire antennas are cheap and you can design or tune them across wide ranges, but I'd question their use with the high noise levels we have these days. I've been using a Wellbrook loop for the last 16 years or so and it's worth its weight in gold. Banishes noise almost completely, especially useful at the lower frequencies. I'd be incapable of hearing *anything* below about s8-9 on the 160m amateur band without it. Not cheap, but you can make one if you're handy.

Reason: No reason
Andy

DanubeBCL
Posts: 179
Joined: Sat Jul 02, 2016 12:39 pm

Re: Great experience with PAR Electronics EF-SWL

Postby DanubeBCL » Fri May 26, 2017 7:01 am

Hi Andy,
I am using two wideband magnetic loop antennas as well. One has 14 m circumference, the other one 5 m. The amplifiers are homebrew (LZ1AQ style, but not using AF transistors). In the beginning I also assumed that magnetic loops will pick up less noise than other types of antennas as many reports from hams and BCLs on the internet claimed. But I had to learn that most of the noise generated in the neighbouring houses below 1 MHz is magnetic! This noise comes from solar inverters, open DSL wires, lawn mowing robots, "smart home" grids and all that stuff. This means that reception below 1 MHz with the loops is becoming more and more worse down to 17 kHz! They pick up the magnetic part of the noise fields. My active whip antenna (which picks up the electric field component) is almost totally quiet down to 17 kHz while all signals on the loops disappear in mud. I also have a 25 m wire with 9:1 transformer. This one is the worst when looking at the noise. It picks up all sorts of noise (electric and magnetic) from all the houses and power lines around.
The type of antenna you can use best very much depends on the sort of noise fields your friendly neighbours produce (and the frequency). You always have to try out. But in the meantime I have given up. The noise level is so high that any type of antenna must fail sooner or later on almost any frequency.

73, Heinrich

Reason: No reason

g1hbe
Posts: 228
Joined: Sat Jan 17, 2015 3:28 pm
Location: Cheshire

Re: Great experience with PAR Electronics EF-SWL

Postby g1hbe » Fri May 26, 2017 10:55 am

That's very interesting, Heinrich.
My experience is just the opposite! On wire antennas and 'mini-whip' types I get terrible noise, especially at MF and LF, but the loop is much quieter and allows signals to be heard. As you say, it depends on what types of QRM you suffer from and how close it originates.
I wonder if your noise problems on the loops are due to them being so large? I'm sure they would be great in a rural setting but in suburban and urban areas maybe a more compact one (maybe around 1m diameter like the Wellbrook) would keep the local noise out, especially as it is easy to rotate them?
On the more stubborn noises which even the loop won't get rid of, I use a phaser-outer which can (but not always) get rid of the noise completely. I think we need to be armed with all tools available!

Reason: No reason
Andy

ultravista
Posts: 17
Joined: Thu Jun 22, 2017 3:40 pm

Re: Great experience with PAR Electronics EF-SWL

Postby ultravista » Sun Jun 25, 2017 8:38 pm

A 45 foot radiator and 9:1 balun, shouldn't this be easy to make @ home?

Is there something special about 45 feet?
Last edited by ultravista on Thu Jan 01, 1970 12:00 am, edited 0 times in total.
Reason: No reason

NoelC
Posts: 72
Joined: Sun Nov 27, 2016 11:50 pm

Re: Great experience with PAR Electronics EF-SWL

Postby NoelC » Fri Jun 30, 2017 5:53 am

The kit is simply a nice package, with good quality components. Yeah, it's just a wire and a balun and an SO-238 connector for coax. But it's a good wire, a nice box, and a quality connector. :)

I haven't noticed a lack of signals at any particular set of frequencies... I pick up stuff all across the shortwave spectrum, as well as FM, air traffic, police/emergency radio stuff, etc. Of course shortwave bands open and close, but I can say that I've picked up WWV (in Florida from Colorado; 2500 miles) at different times at S+10 or higher on all frequencies including 25 MHz.

What would help illustrate? Screen grabs of spectra at various frequencies so you can see the relative QRN levels? I'll do that if anyone thinks it could be helpful.

-Noel

Reason: No reason


Return to “SDR Antennas”

Who is online

Users browsing this forum: No registered users and 2 guests