[Elecraft] KX1 and EFHW antenna

[Don Wilhelm]

  Sante,

The KX1 antenna tuner has limited range due to its small size, so I 
would not expect it to tune an end-fed 40 meter dipole on 80 meters.

In addition, a half size end fed dipole is no longer an end fed dipole, 
it is just a piece of wire.  The "half wave" part says that is true.  A 
1/4 wave wire without any other component is only half of a half-wave 
dipole no matter where it is fed.

What I would suggest instead is the so-called W3EDP antenna connected to 
the KX1 with no feedline.  The radiator is 89 feet (27.13 meters) and 
the counterpoise for 3.5 MHz is 17 feet (5.18m).

Take a look at http://www.zerobeat.net/g3ycc/w3edp.htm.  On 80 meters, 
you may need the auxiliary (external) tuning circuit, but once you have 
tuned the external circuit inside any one band, you can use the KX1 
internal tuner as you move around in the band.

73,
Don W3FPR

On 7/10/2011 5:21 PM, Sante - IK0HBN wrote:
> Hi all,
> there is a plenty of schematic about End Fed Half Wave antenna, but
> all them are within the range 40-10 meter. Is there one of you who
> was able to run it with a KX1 in the range 80-20 meter? The idea of
> getting a wire hanged somewhere, without long radials if not a 2-3
> meters counterpoise is very intriguing.
> BTW with the internal tuner, should KX1 be able to match it without
> another external tuner, just to make things simpler with few things
> to bring along?
> Ciao
> Sante
>