Here’s a thought: if one can use a fan dipole to make an inverted vee cover
both 80 and 75, how about a fan reflector?
73, kelly, ve4xt
> On Mar 31, 2017, at 9:30 AM, Grant Saviers <grants2@pacbell.net> wrote:
>
> I think you need to model what you are attempting. You don't mention the
> antenna support and if it is a tower then there is a fair amount of
> interaction with the V. However, a 39' boom will help if the tower is at the
> midpoint. I've modeled a number of phased 80m delta loops on a 89' tower and
> you might consider delta loops vs an inv. V. With a 120' support and a 39'
> boom you've got a good start for a great antenna.
>
> For it to perform as a parasitic beam on two frequencies, then the inductance
> needs to be added to both elements. Using a tuner to get acceptable swr
> doesn't change the pattern, which may even reverse from what you want. Cut
> for SSB and add feedpoint inductance for CW and perhaps have two values of L
> to cover most of 3500 to 3840 or so. PVC junction boxes on the boom ends
> with relays for switching. This is how my 2L JKantenna beam covers 3500 to
> 3840.
>
> Another (and probably better) choice is to drive the two V or loop elements
> out of phase to create the pattern. You may find a design that has enough
> swr bandwidth for SSB and CW. Optimize the (switched) phasing lengths for
> pattern since swr coax losses are low on 80m and your tuner can make the amp
> happy. A quick mod of my phased loop model says this may work.
>
> check out
>
> http://www.transduction.com/PDV.pdf
>
> and W8WWV's work on 80m V
> http://www.seed-solutions.com/gregordy/Amateur%20Radio/Experimentation/IVee80.htm
>
> there is also a lengthy blog like tale of phasing two V's on a tower (gave up
> after 3 years) but I can't find it now, perhaps other TT'ers have the link.
>
> Grant KZ1W
>
>
>
> On 3/31/2017 5:00 AM, Martin Pelt wrote:
>> I am putting a 80 meter 2 element inverted vee beam up. It will be at 120
>> feet with 39 foot boom.
>>
>> I have 2 questions dealing with switching from phone to cw without lowering
>> elements and using jumpers.
>>
>> I plan to use ladder line on driven element coming down to tuner to switch
>> from cw/ssb. Will this work or is there a better way ?
>>
>> On the reflector I thought maybe cutting it for ssb the having inductor
>> with relay at the center to switch to CW. Is this the best way ? If so how
>> can I easily measure resonate frequency with inductor inserted at the
>> center ?
>>
>> 73 Martin N4UU
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