[TowerTalk] Dipole fed with balanced line?

[Eddy Swynar]

On 2012-01-16, at 8:41 AM, Ken wrote:

> Actually this setup is covered in this month's QST "The Doctor Is In" column with a couple of references to older QST articles.
> 
> A center fed dipole with open wire or ladder line is a very good multi band antenna if you have a tuner which will feed it.  A half wave at the lowest frequency is the classic antenna and is covered in the Handbook and Antenna Book.   Some people find that the high impedance of the full wave (e.g. 130' on 40m) is difficult for some tuners to handle and a 100' length is a popular size for 80m and up.   Myself, I prefer not to give up that extra length on 80m.
> 
> Antennas like this do not have to be precisely tuned.   135', 130', 125' all will give essentially the same performance.   100' will give a slightly reduced performance on 80m. 
> 
> And additional plus of an antenna like this is that it will work very well on the WARC bands like 60 and 30m. 
> 
> I'm currently using an antenna like this.  40' of feedline to a 4:1 balun outside the house, then coax directly to the Elecraft K3.  The K3's internal tuner handles it perfectly on all the bands 80 through 6m. 
> 

Hi Ken et al,

I had mis-givings here about feeding my 160-meter half-wave inverted "V" dipole (50' at the apex) with foam-type 300-ohm TV twin-lead---and using it on all bands from 160- to 10-meters---but my cares have been quickly laid to rest...

That sort of a multi-band tuned dipole is wonderful---and it even has the added bonus of some "long wire" gain on 80- through to 10-meters...this, despite the fact that it has good, round-the-compass coverage, what with the smaller, "fill-in" lobes radiated by the antenna, which increase in number the higher the frequency band.

One thing to pay attention to, though, is the feeder length: I settled upon one of the recommended lengths shown in my older small-sized ARRL ANTENNA HANDBOOK, otherwise I simply could not tune the thing on some bands with my transmatch...

~73~ de Eddy VE3CUI - VE3XZ