[Elecraft] AX1 Loaded Whip Antenna - Elevation and Counterpoise?

[David Gilbert]

Scroll down to the original post.  We were talking about a KX2 with an 
internal antenna tuner.  Presumably the tuner works as it should to 
present the proper load to the finals.

73,
Dave   AB7E


On 8/7/2019 5:29 PM, Mark Goldberg wrote:
> You need to take into account the radio finals. When the SWR is high, 
> My KX3 cuts back because it gets too much reflected power. I expect 
> the KX3, and in fact any other radio or amplifier is similar. 15:1 is 
> about half the power coming back.
>
> Regards,
>
> Mark
> W7MLG
>
>
> On Wed, Aug 7, 2019 at 5:14 PM David Gilbert <xdavid at cis-broadband.com 
> <mailto:xdavid at cis-broadband.com>> wrote:
>
>
>     Rather little of this discussion makes sense to me.
>
>     Let's look at this realistically:
>
>     1.  The antenna tuner in the KX2 is rated to be good up to 10:1 SWR.
>     Let's assume it's good to 15:1.
>
>     2.  Let's assume you're using a decent cable for portable
>     operation like
>     RG-8X.
>
>     3.  Let's assume that the length of your coax when operating
>     portable is
>     not much more than 30 feet long.
>
>     4.  Let's assume under the current solar flux conditions you're
>     spending
>     most of your time on 20m or lower in frequency.
>
>     30 feet of RG-8X has a loss of 0.4 db or less for that length at
>     those
>     frequencies, and per the charts in the link below the additional loss
>     due to a 15:1 SWR is no more than 2 dB.
>
>     http://www.astrosurf.com/luxorion/qsl-transmission-line2.htm
>
>     Maybe it's just me, but I don't think that justifies dragging along a
>     remote tuner.  You could recover a heck of a lot more dB by simply
>     bringing a somewhat larger portable antenna.
>
>     73,
>     Dave   AB7E
>
>
>
>     On 8/7/2019 3:57 PM, Phil Hystad via Elecraft wrote:
>     > Sounds like an idea worth trying — I have always wondered about
>     the coax loss between my KX3/KX2 and my portable antenna no matter
>     which one it is (i.e. AX-1, Wire and counterpoise wires,
>     Buddipole, etc.).
>     >
>     > But, really glad I did not sell the T1 on several occasions of
>     thinking about selling it.  I have not used my T1 since I sold my
>     KX1 almost three years ago.
>     >
>     > phil, K7PEH
>     >
>     >> On Aug 7, 2019, at 10:23 AM, Wayne Burdick <n6kr at elecraft.com
>     <mailto:n6kr at elecraft.com>> wrote:
>     >>
>     >> I think a T1 at the base would make a noticeable difference if
>     the coax were more than a few feet long and the whip's resonance
>     well removed from the target operating frequency. Short whips can
>     be extremely narrow-banded.
>     >>
>     >> Wayne
>     >>
>     >>
>     >>
>     >>
>     >>> On Aug 7, 2019, at 7:40 AM, Don Wilhelm
>     <donwilh at embarqmail.com <mailto:donwilh at embarqmail.com>> wrote:
>     >>>
>     >>> Bret,
>     >>>
>     >>> Yes, the T1 mounted at the antenna will reduce the potential
>     loss in the coax.
>     >>>
>     >>> Will you notice the difference?  Maybe or maybe not.
>     >>>
>     >>> 73,
>     >>> Don W3FPR
>     >>>
>     >>> On 8/7/2019 7:54 AM, MaverickNH wrote:
>     >>>> It comes to mind I have an Elecraft T1 ATU I might try
>     attaching directly to
>     >>>> the base of the AX1 rather than relying on the KX2 ATU
>     25-40ft from the
>     >>>> antenna. I try to operate closer but sometimes have to run
>     that RG58 to
>     >>>> clear obstructions. Thoughts?
>