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How about this for a /P antenna?


#1

http://www.tak-tenna.com/

Scroll to the bottom. This looks like a neat directional HF antenna.

Peter


#2

In reply to ON3WAB:

Yes very neat, but with a very poor efficiency, perhaps less than ten percent -probably lower compared to a full-size dipole. The active part is the horizontal dipole, maybe just 1 meter long and the “coils” acts both as an capacitive hats and a coil to electrically shorten the antenna, but the coil does not contribute to the radiation of the signal.

You can compare this to a short whip with linear loading - the bandwidth will be very narrow, a few kHz.

My personal opinion, as usual one should read the specs carefully and look between the promising lines, in my eye this is an expensive air-cooled dummy load, it will work but you can get much more with less money…


#3

In reply to ON3WAB

Love the Hamuniverse “impartial review”!

Reckon the reviewer must be a scriptwriter for a shopping channel…

73 de Paul G4MD


#4

In reply to SM5KRI:

an expensive air-cooled dummy load

loool - big lough, Krister.

In the past I used also strange kind of antennas in the hope, to find the ultimate agreement between EURO (or D-Mark), SPACE, GAIN. But I learned - there is none!

I am not impressed, when owners of such antennas tell: “I worked … (PY/VK/ZS/JA)”. In a big contest (CQWW) I work with a Hustler Mobile Antenna the other side of the world - QRP! - but it is not my credit … the antennas of the DX station makes the job.

Don’t believe in wonder-antennas!

73 …


#5

In reply to G4MD:

Think I will get one Paul… if only to stop people asking why I am taking a fishing pole up a mountain! :wink:

73, Gerald


#6

In reply to G4OIG:

I always say I have been told the fishing is good on the summit, I get some strange looks… lol

With that HF you just know they are going to ask why you have a rotary washing line if you take that up!!

73 Steve


#7

In reply to 2E0KPO:

Yes, think I will stick to telling people that I am looking for the delicious brown mountain trout that only lives within 25m of a summit.

73, Gerald


#8

In reply to G4OIG:

Hi Gerald

It could be the answer to those pileups…if no-one can hear you no-one will call you…oops forgot for a moment, being able to hear the other station no longer seems to be a pre-requisite for trying to QSO…

73 de Paul G4MD


#9

In reply to 2E0KPO:

With that HF you just know they are going to ask why you have a rotary
washing line

A rotary washing line would probably work better Steve…


#10

In reply to G4MD:

You could always cover the ends with fabric and tell folk it’s a new style brolly.

Mike GW0DSP


#11

And I thought you were all going to like it :o)


#12

In reply to ON3WAB:

We do… :wink:


#13

In reply to SM5KRI:

You can compare this to a short whip with linear loading - the
bandwidth will be very narrow, a few kHz.

That antenna has broader bandwidth than few kHz. Anyway the radiation efficiency depends on the radiation resistance of the antenna versus the resistive losses in the antenna and surroundings including ground. Small antennas have small radiation resistance so you need to keep the resistive losses also small. One example is the magnetic loop, which has high-Q and narrow bandwidth, for example from PY1AHD

http://hps.infolink.com.br/py1ahd/gallery26.htm

The normal size wire antennas are easier to handle and tune though.

73, Jaakko OH7BF/F5VGL