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

[Wes]

I haven't been following this thread closely but I think Dave makes good 
points.  As to the final fold-back, if I waded through this correctly, I 
understand that the OP has the built-in tuner in his KX2.  That solves that issue.

BTW, SWR = 15:1 is a return loss of about 1.1 dB, not 3 dB.

Wes  N7WS


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>
> 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
>>