[Antennas] simple 160 ant.

Mon Oct 4 23:09:03 EDT 2004

> In all my years on the air, I have never been on 160. I would 
> like to try it this winter, but not looking to spend a great 
> deal of time on a complex antenna. I just bought a set of 
> Unadilla KW80F - 80 meter traps. I have an 80 meter 
> inverted V now - apex at 70ft, I have trees that will allow 
> the longer wire and will have the ends about 30 feet off the 
> ground. I know this is not the ideal antenna, but it should 
> at least get me on 160. 

For xmit, it should be ok....but for rcv, a low noise antenna like a
beverage or tuned loop would be best on 160..
(if you could get a nice vertical with a good ground radial system, that
would be best for xmit!)
>> My questions are:
>> Do I make the 80 mtr section longer or shorter when using traps ? 

They usually are the same as normal...the traps should isolate the
longer sections off when operating on 75/80 mtrs but there could be some
minor interaction...hard to say....you should probably go longer on the
80m sections then trim for resonance
> Do I make the overall length as if I were building a dipole for 160 ? 

Again, make it longer and then trim for min SWR on 160....be sure to
check your 80 mtr resonance to make sure it hasn't changed (it shouldn't
but you know how theory works :)
 
> Would I be better to just make a separate 160 inverted V and 
> forget the traps ?

For best bandwidth, yes! the traps will cause your bandwidth especially
on 160 to be narrower than a standard dipole..
> Is the formula (468/F) correct for a trapped dipole/inverted V ?

Usuaully, BUT YMMV (Your Mileage May Vary :)
Chris
WB5ITT