[TenTec] New and Improved Terminology (NVIS origins)

[Rsoifer at aol.com]

I, too, have always had good results with vertical dipoles.  Pat  Hawker 
wrote one of mine up in 1970 or 1971.  It consisted of a 12AVQ trap  vertical 
for the top half, and quarter-wavelength counterpoise wires cut for 10,  15 
and 20 meters for the lower half.  The wires (actually conductors of a  
4-conductor rotator cable) were run straight down the TV mast on which the  
vertical was mounted, using spacers of the type intended for TV twin-lead.   The 
mast, in turn, was secured to a rooftop chimney with TV hardware.  With  
it, I worked something like 225 countries in 2 years with 100 watts, mostly on 
 20 CW.  When we moved out of the apartment complex where the antenna was, 
I  left the antenna in place.  About 20 years later I drove back to take a  
look at the old place.  The antenna was still there!
 
73 Ray W2RS
 
 
In a message dated 1/5/2011 5:28:27 P.M. GMT Standard Time, romers at shaw.ca  
writes:

I will  confirm Rick's results. Almost the same antenna here -- 30 ft of
tower  insulated from ground on my sun deck with a 24 ft aluminum rod
insulated  from the top of the tower; the rod fed against the tower with
ladder line.  

A non-resonant, non symmetrical, vertical dipole -- works 80 thru  10
with an old Johnson Matchbox. Works everything I can hear and I can  hear
plenty.

Jerome - VA7VV
Vancouver

On Wed, 2011-01-05  at 11:58 -0500, Rick - NJ0IP / DJ0IP wrote:
> Jerry, let me throw two  things at you:
> 
> 1. I think a horizontal loop is a pretty good  radiator, straight up.
> 
> 2. The vertical dipole antenna I've  described has been in use here for
> nearly 20 years, at 3 different  home QTH's and countless portable
> operations.  On 80m where one  would think it is too short to work, I 
found
> that I was always just as  loud working stateside, JA, or VK, etc. on the
> short vertical dipole,  as I was on my full size horizontal dipole which 
was
> only 40 ft.  up.  Nobody on this earth can convince me I'm wrong because I
>  have a logbook full of QSOs to prove it. (don't forget, I was in  
Germany)
> 
> So, if someone tells me they can't get on 80m  because they have no room, 
I
> just say humbug!
> 
> You can  get a good fiberglass pole, 40 ft long, for about $120 from
> companies  like Spiderbeam.
> You can get 100 ft. of openwire (300 ohm or 450 ohm)  for probably $35.
> Add 40 ft. of copper wire and you have a good 80m  antenna (well 80 thru 
10m
> antenna).
> 
> While living in  Oklahoma (until last week), I used a bigger version.
> Using a 60 ft.  Spiderbeam pole, I built my vertical dipole with 30' per
> side.
>  On 80m in CQWW CW with about 800w, I was able to work every dx station  
that
> came up on the DX cluster, be it in Africa, or anywhere else,  with just 
one
> or two calls.
> 
> As I said, people highly  underestimate how well these antennas work.
> L.B. Cebik W4RNL (SK)  didn't.  He too was a fan of the vertical dipole.
> 
>  Actually, the main reason it works so well is because most people use
>  antennas on 80m which are worse!  Hi
> 
> 
> I agree,  you should have good success with a vertical mounted on the 
metal
>  building.
> I've always wanted to try that but never had the  building.
> 
> 73
> Rick
> 
> 
>  -----Original Message-----
> From: tentec-bounces at contesting.com  
[mailto:tentec-bounces at contesting.com]
> On Behalf Of Dr. Gerald N.  Johnson
> Sent: Wednesday, January 05, 2011 11:00 AM
> To:  tentec at contesting.com
> Subject: Re: [TenTec] New and Improved  Terminology (NVIS origins)
> 
> 
> 
> On 1/5/2011 4:42  AM, Rick - NJ0IP / DJ0IP wrote:
> > Ken,
> >
> > I  don't know if the low angle efficiency falls off faster than the high
>  > angle radiation.
> > I can't remember ever reading that, but I  have probably only read "a 
drop
> in
> > the bucket" of all  there is.
> 
> Because of extended ground losses, no antenna has  strong radiation 
> exactly at the horizon. It can try but that RF gets  absorbed.
> >
> > I do know that I changed my attitude about  verticals since reading 
Rudy's
> > papers.
> >
> >  I also know that there is no reason to ever use a vertical with
>  inefficient
> > ground.
> > Instead I use a vertical dipole,  30 to 40 ft. overall length, fed in 
the
> > middle with openwire, and  matched with a matchbox inside the shack.
> > No radials, yet still  has fairly good efficiency.
> 
> Good efficiency on 40 and higher  bands, but rotten on 160 where a good 
> center fed dipole would be 240  feet tall.
> >
> > I can't imagine why people continue to go  with the traditional design,
> > except for the case that they are  willing to lay down a complex ground
> > system (or 4 elevated  radials per band).
> 
> I have a metal machine shed 48 x 56', I  figure a trap vertical at the 
> middle of all that metal won't need  longer radials for the low bands to 
> work decently. I've used a trap  vertical on a 30' diameter steel grain 
> bin with super results 40  through 10.
> >
> > 73
> > Rick
>  >
> >
> A poor ground plane contributes a poor (e.g.  resistive) ground in series 
> with the antenna and so while it improves  the bandwidth (and often the 
> impedance match), it hurts radiation  efficiency. But it gets out better 
> than no antenna at all.
>  
> 73, Jerry, K0CQ
>  _______________________________________________
> TenTec mailing  list
> TenTec at contesting.com
>  http://lists.contesting.com/mailman/listinfo/tentec
> 
>  _______________________________________________
> TenTec mailing  list
> TenTec at contesting.com
>  http://lists.contesting.com/mailman/listinfo/tentec


_______________________________________________
TenTec  mailing  list
TenTec at contesting.com
http://lists.contesting.com/mailman/listinfo/tentec