Shortwave Antenna - Overwhelmed

[knathan]

I've perused the radioreference.com forums and overwhelmed myself with web searching for a shortwave antenna to enhance the reception of my new Grundig G3. I like building things myself, so I first focused on plans and kits. I finally followed advice I had read in many forums about "throwing a wire out the window. Anything is better than the antenna on the radio alone." Well I got the point - just start. So I soldered a 50 foot wire to the center of a 1/8" plug and tried it. I had only minor improvement - I'm looking for better.

I've found some pre-made (receive only) antennae that don't require the usual 140 feet or so of distance. I have a roof ridge that is 56 feet long. Though they're shorter, they claim to work with a broad range of bands. One for example is the Eavesdropper-T (11-60M). It is 43 feet overall, so I could mount that easily. It is just one of many that I'm sure exists, and is mentioned only as a reference.

Before I spend my hard earned money or commit many hours of my valuable time, I thought it best that I ask for the advice from experienced radio operators. Understanding there are variables and uncertainties with any given antenna / location system, what is a good antenna for my space? I am not opposed to building, but it seems the DIY plans are either too general, assume I have more technical knowledge of things like baluns, or missing simple information that for me is a show stopper. I'm willing to wind wires, drive ground rods, and mount masts on my roof. And I'm willing to spend money. But I want to be able to proceed with a reasonable amount of confidence that I'm on the right path.

I'd appreciate any help.

 

[davedaver1]

Wow, nobody answered this? You don't have to get really fancy - just as much wire as you can get out usually works well for SWLing. The expensive trapped and coiled antennas don't bring much to the table, IMHO, but may optimize lengths for certain bands - but at a pretty steep cost. I have an Icom IC-R20 that only has a 40 foot wire going from the house to a nearby tree - which works great for casual listening.

A slinky antenna may help you - it compresses a LOT of wire into a much shorter space.

Check out The WireMan - Your source for coax, connectors, wire, baluns,and more! for lots of good material and some kits too, in case you want to build something more than just a wire antenna. I built a 400 foot loop that works really well and is pretty quiet too (it's for a ham transceiver, but I SWL with it also).

Good luck!

 

[ka3jjz]

The G3, and portables like this, often don't take well to long antennas. They're simply not built to handle the large amount of signal antennas like the the Eavesdropper would provide. Overloading is the usual result. One way this issue arises is if you have a MW station showing up in the shortwave bands, or other shortwave stations repeating (sometimes quite distorted) where they don't belong.

You might get away with it seeing as you're in the Midwest but personally speaking I wouldn't recommend it. Since you like to build, you might consider the Carpet Loop, the link for which is in our Loops wiki (see the last link in the Technical section). You can make the loop element as small or as big as you wish, the construction isn't difficult, and you get a little lesson on how L matching works. The loop itself could be put outdoors - and that's much better than having it inside, especially if you can get it away from all the noise sources...

A win-win all around. I built one when I lived in Anne Arundel county, and it worked pretty well with my RX320. best regards..Mike

 

[n2pqq]

I use the PAR antenna with my Perseus radio .

PAR High-Performance Shortwave Antenna

Keep in mind the radio may not be able to handle the signal due to filtering in radio.

You may end up with overloading of radio.

Good luck and let us know how it turns out.

 

[ka3jjz]

I've no doubt that the Perseus would work quite well with the PAR. However, we're talking about a small portable with the G3, and it's doubtful it would work real well with a lo impedance input anyway.

Besides the 2 radios couldn't be any further apart in terms of the technology, for sure

Putting 50 foot on the radio is probably as good as you can expect, really. If there's an antenna switch on the side that switches between the whip and the wire, make sure it's in the wire position.

best regards..Mike

 

[ridgescan]

Given the sensitivity of the portable explained here, why not try the metal tape measure as your SWL antenna. I have found it to be pretty effective on the Patrolman

YouTube - ‪Metal Tape Measure SWL Antenna‬‏

 

[N1BHH]

Most of your portable type radios come with a roll up antenna of about 15 feet or so. I got one with my YachtBoy when I bought it years ago. That alone does quite well, but using anything that is 100 feet long will overload your receiver and make your experience all the more worse. A simple antenna will do the job. And don't go spending hundreds on antennas, they don't work well on this type radio. I build my antennas, you'll waste your money buying prefabricated crap.

 

[knathan]

Thank You!

I anxiously and frequently checked for responses to my question. After many weeks went by with none, I gave up. This morning, after more than a half a year away, I thought I'd check again, expecting still no replies. I was pleasantly surprised to find and read these. Thank you.

I think the key is the G3. My experience with the wire is explained with your G3 comments and its capabilities. I didn't get clearer signals - just more noise.

My listening experience was greatly enhanced by using web sites like Shortwave Radio - NASWA: The North American Shortwave Association and links I found from it. Beginning with some known broadcast times and frequencies and getting pointers to frequency bands versus USB and LSB have vastly increased my ability to find clear stations or ham transmissions.

Thanks again for the pointers. Since I like to build things, I may give the carpet loop antenna a try. But I will certainly be researching additional radios first. The G3 worked well for my occasional listening, but the bug has bit. SWL is so intriguing. I want more!

 

[comoman]

I think "Overwhelmed" is a bit understated.

After having read everything I can lay my hands on I'm still a little confused about the best antenna, best way to hang it and which direction and height is the best. I realize it will vary somewhat depending on one's location but I haven't been able to realize any reception improvement no mater where and how the antenna is mounted. I don't read much about height of SWL only antennas.

 

[ka3jjz]

That's understandable. There are so many different antenna designs, it can be mind-boggling just to try to get the right one for your application.

The height above ground issue really comes under 2 general concepts;

a. Trying to get the antenna away from your home (and potential noise sources)

b. For directional antennas, height is important for certain types of antennas. This applies to dipoles, for example - keeping the antenna at least 1/4 wavelength away from the ground will help in isolating the antenna from interacting with the earth beneath it. The standard formula for this is 234 / Fmhz where Fmhz is the frequency in Mhz. The answer will be in feet.

Now this is far more critical for ham transmitting antennas than for receiving - although it can and does play a role there, too.

Before we even try to tackle which antenna is best - and really, there is no such thing, the question itself is too vague to properly answer - there are a few questions to be answered.

The first one - what is the receiver? Small portables like the ones from Kaito, Degen, etc. are not real good at handling very long antennas - they're generally built for rather short (and generally speaking, inefficient) antennas and loops. Putting a long antenna - say a 100 foot random wire - would likely end up overloading the radio.

Are there better choices? Yes - SDRs, amateur transceivers (most modern ones have general coverage receivers built in) and the rapidly fading desktop market. All of these are more likely to handle the amount of energy a 100 foot antenna would deliver

Now another question - can you put something outdoors? That's far and away preferable, and getting it away from the home is important for the reason mentioned earlier. How much space do you have to play with?

This just barely scratches the surface. Please give a little more detail as to your physical situation (what radio, how much land available, indoor/outdoor, etc.) and lots of folks can give more detailed recommendations

Mike