I agree, the QSO rate is slower than most contests and can be frustrating
without the right antenna(s). The noise level can do you in too.
My main antenna is an Inverted L with the vertical portion up about 55
feet. The radial system is what makes this antenna work.
The soil conductivity is extremely poor at my QTH. So I laid down 32 1/4
wavelength radials (about 4000 feet of copper) right on top of the ground
in a 360 degree pattern (more or less). I own a network analyzer so I
monitored the impedance as I was laying down the radials. The impedance
was very high (high ground losses) with no radials but as I added radials
I could see the impedance fall thru 75 ohms, then 50 ohms to 40 ohms with
16 radials. Adding another 16 radials got my impedance down to 35 ohms.
This antenna alone got me 400 QSO's in about eight hours of operating
including the west coast, Europe and South America. To me, this wasn't
bad for a start.
73,
John
N2HMM
> A lot of folks are "defeated" by the 160m SSB contest, the most work per
> Q of any big contest, IMO.
>
> More wire, even elevated you 2', will help shield the earth and reduce
> loss, 65' is too short for 160 so tuning isn't going to happen, and it
> might not make any difference since they are tied to earth. You will
> reduce ground loss by a few more ohms and that is good.
>
> The biggest improvement you can make with limited radial space, is to
> add top loading to increase the radiation resistance. There are a
> number of ways to do that L, T, umbrella, disc, etc. Now a lot depends
> on what you have for supports around the butternut. The top loading
> will help both 80 and 160 with your 32' vertical but 40m will start to
> look like a 1/2wl, hard to feed. The loading coil will need adjustment
> for 80 and 160.
>
> There is a lot written about this topic google top loading verticals for
> some alternatives.
>
> Grant KZ1W
>
>
>
> On 3/2/2016 19:57 PM, Jon Suehiro wrote:
>> A bit off the topic, but - I don't think have seen any discussion in the
>> subject --- ground radials.
>>
>>
>>
>> I have Butternut HF2V (with 160/30 options) and placed approx 12 x 15'
>> ground screen around the vertical, and 35 x 15 ~ 40' gage #14 wires on
>> the
>> ground at my city lot.
>>
>>
>>
>> Completely defeated in 160 phone contest and felt like running through
>> 30dB
>> ATT on 160 (estimated radiation efficiency of 5%).
>>
>>
>>
>> Always the discussion is raised or on/in ground. I can place 4 x 65'
>> radial
>> wires along the wood fence approx. 20 ~ 30" above ground (cannot place
>> on
>> the ground) in addition to the current system.
>>
>>
>>
>> 1. Can raised and on/in radials mixed ?
>>
>> 2. If 2' above ground is too high as on/in ground, do they need to
>> be
>> tuned or can be random length ?
>>
>>
>>
>> Thanks.
>>
>>
>>
>> NN5T Jon
>>
>>
>>
>> _______________________________________________
>>
>>
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>
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