Wednesday, April 08, 2009

QRP and a little antenna

One of the nice features of Blogger is that it allows you to subscribe to or "follow" other blogs, so that you can easily see when any of them receive a new posting. I have just added N8ZYA's Radio Blog to my list - whose tag line is "QRP and a little more."

N8ZYA operates using an IC-703 QRP transceiver and an indoor antenna that you can see in the picture at the top of his blog. It looks like a hospital drip stand! I think it is a pair of "Isotron" antennas, a type of limited-space antenna sold in the USA.

Discussions about how well the Isotrons work (or don't) can be a bit controversial. These antennas get a lot of 5 out of 5 reviews at However, many sceptics don't believe they can really work, as they appear to defy all known laws of physics. I'd love to get my hands on one just to try it head to head against my MFJ Magnetic Loop, the only limited space antenna I know of that really does work.

In my opinion, the Isotron only gets 5/5 ratings because anything that isn't a screened dummy load will radiate some RF, and people who have low expectations of what an indoor or stealth antenna can achieve are easily impressed. It would be nice to be proved wrong, though.

1 comment:

Anonymous said...

It's an astounding antenna and I can't begin tell you "how" or "why" it works. But it works, and works well.

I'm living in a "historic district" at an elevation of 600 ft. I have two 400 ft "hills" on each side of me, and an 8 story apartment building next door. There's also quite a bit of electrical noise in this area and my antenna's are mounted "indoors" in a spare room.

It's no Dummy (a pun on words) best contacts so far have been 4,6000 miles into Finland, and several stations in Eastern Europe. (Portugal, Belgium, Spain, France, Italy, Poland, Germany, and the Isle of Man). For a "restricted antenna area" , I've had a blast with this thing and 5 watts QRP.

The vast majority of these contacts (20 meters) have been "contest stations". I can be heard in "pile ups" more often that you would think.

But my favorite band is 40 meters, where I get 579 and 599 reports (quite often) at distances close to the 1,000 mile mark. I get the biggest joy out of QRP contacts with simple wire antennas.

The vast majority of my contacts have been with the solar flux in the 68-72 range. (Yes, it's quite a puzzle)


John N8ZYA