I installed a GAP Voyager vertical about the beginning of October. The
now. I was curious why and the frozen ground theory makes sense.
> It would have to stretch about 4-5ft to see a difference of 50Khz in
> resonance. I doubt it has stretched that far.
>
> I see huge swings in my inverted L resonance (with 4 elevated radials) and
> it is 100% related the ground freezing and unfreezing and ground
> conductivity changing.
>
> My 2:1 SWR points are about 80Khz apart. 2 months ago my resonance was
> about 1850khz. Today it has slice up and the end result is that my SWR at
> the bottom of the band is now 2.3:1 when it used to be 1.9:1. That is in 2
> readings 28 days apart. My new low edge is 1813Khz. The easy fix is to
> add 3ft tot he vertical part. In the spring, I will have to remove it
> again.
>
> I have before and after screen shots, but I don't think I can send them to
> this reflector. If someone wants to see them, let me know and I'll send
> them to you.
>
> Like Don said, his broad bandwidth is due to ground losses.
>
> Mike va3mw
>
>
>
> On Mon, Dec 3, 2018 at 10:30 AM Don Wilhelm <
[hidden email]> wrote:
>
>> Not necessarily - notice the relatively flat SWR (less than 2:1) over a
>> large frequency range (for 160 meters). That normally means that the
>> antenna is acting more like a resistance than a radiator.
>>
>> I would expect the SWR on 160 meters to be low only over a 25kHz or at
>> most 50kHz range of the band.
>>
>> When the SWR bandwidth of an antenna increases, you should be looking
>> for a problem in that feedline, antenna to feedline connections or in
>> the case of a vertical, the ground radial system.
>>
>> One possibility is that the radial wires installed were aluminum - they
>> do not last very long in the ground, for some reason, moles like to chew
>> on them.
>>
>> 73,
>> Don W3FPR
>>
>> On 12/3/2018 9:18 AM, Don Roberts via Elecraft wrote:
>>> Lee, it looks like your inverted L wire has stretched. Check with an
>> antenna analyzer and you will probably see your resonate frequency is lower
>> than 1.8 Mhz. Perhaps time to do some triming.
>> ______________________________________________________________
>> Elecraft mailing list
>> Home:
http://mailman.qth.net/mailman/listinfo/elecraft>> Help:
http://mailman.qth.net/mmfaq.htm>> Post: mailto:
[hidden email]
>>
>> This list hosted by:
http://www.qsl.net>> Please help support this email list:
http://www.qsl.net/donate.html>> Message delivered to
[hidden email]
>>
> ______________________________________________________________
> Elecraft mailing list
> Home:
http://mailman.qth.net/mailman/listinfo/elecraft> Help:
http://mailman.qth.net/mmfaq.htm> Post: mailto:
[hidden email]
>
> This list hosted by:
http://www.qsl.net> Please help support this email list:
http://www.qsl.net/donate.html> Message delivered to
[hidden email]