[TowerTalk] 80 meter antenna choice

[Grant Saviers]

Another factor to consider is arrival angles and I don't know if HFTA 
has data for V31 region.  That would matter a lot for contesting (maybe 
25+ deg EU and US?), but then lower would be better for DX into Asia/VU.

I have to wonder if K3LR's e4sq vs dipole experience is related to the 
angles into WPA from EU. With the dipole so high it's peak angle might 
be too low vs the 4 sq.

I second the comment that an inverted V hanging on a tower with Yagis 
can have interaction problems, at least this was true with my modeling 
attempts to get an 80m pattern with some gain below 10deg which is the 
EU arrival stat into WWA.  My 86' rotatable dipole at 102' feet couldn't 
do the job.  A JK 2L yagi at 157' solved that problem for me, more gain 
db's and lower angle db's, >6 total. For a rotatable large antenna, JK 
knows how to make them that last.

Grant KZ1W


On 7/7/2020 12:39, Richard Thorne wrote:
> Bill,
> 
> I've been real happy with a JK801 rotatable dipole at 138'.  I use a 
> Green Heron RT-21dc (the other option is an MFJ-1924 mobile antenna 
> controller) to control the Tornado Tuner.  It gives me full band 
> coverage in 40khz increments.
> 
> According to Ken's modeling (unconfirmed by me as I have no clue how to 
> model) a JK801 at a 1/2 wave length in height is at least equal to a 
> good 4 square.
> 
> https://jkantennas.com/jk801.html
> 
> Rich - N5ZC
> 
> 
> 
> On 7/7/2020 9:50 AM, Bill via TowerTalk wrote:
>> I've pretty well figured out what I will be doing on 40-6 meters.  
>> However, 80 is still undecided.  Shunt feeding the tower is not going 
>> to work since I have all kinds of rotating antennas up the side of the 
>> tower.  So, I'm left with three solutions.
>> Since the last guy point is at 96 ft I could have two inverted Vees 
>> apexed at 96 feet down to around 60 ft on the ends, at right angles to 
>> each other.  That would give me the ability to switch directions and 
>> gain/lose around 5-10 db.
>> Second choice is to have a full size wire vertical with 60 full sized 
>> radials over average ground.
>> Third choice is more complex-  a wire 4 square but...although the SE 
>> and SW facing verticals would be pretty close to having a good radial 
>> system The NE facing one is pretty limited due to lot lines and the 
>> location of the house/garage and the NW facing antenna is even more 
>> limited by the same constraints.  This one has a driveway in the way.  
>> Most of the decent sized radials would be pointing away from the 
>> direction the NE and NW are facing and the others would be fairly short.
>> Of course laying down the radials for the 4 square is quite a chore 
>> and I would hate to go through all that work to come up with crappy 
>> system.  Easiest of course, would be the inverted Vees.  I've used 
>> this system in the past and it performed quite well.  I'm concerned 
>> the lack of similar radial systems would ruin the F/B and gain and the 
>> compromised radial system of two of the antennas would also be an issue.
>> Your thoughts?
>> Bill KH7XS/K4XS  (soon to be V31XX)
>>
>> Location of the station is V31 and interest is contesting and DXing
>> _______________________________________________
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