Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Old March 5th 11, 04:25 PM
Member
 
First recorded activity by RadioBanter: Feb 2011
Location: Tampa florida
Posts: 33
Default Trap Vertical Antenna Questions

I have a tree here in the Tampa Florida area just begging to have a Hustler 4 or 5 BTV stuck in it. I have had great luck with ground mounted Hustler Verticals when I lived near the sal****er of Tampa Bay. I am now in Brandon Florida, east of Tampa, and far from salt water. I have stuck Hustler Verticals in trees before with radials for most bands, but had access to a bucket truck back then, and did not have stents in my heart. I got to thinking WHY not take a hustler vertical with only ONE Tuned "radial" for each band in the form of the lower part of a 1/2 wave dipole. In other words, make the Hustler Vertical into a multi band center fed 1/2 wave dipole. It will be a lot easier to deal with only one radial for each band if they hang straight down the tree vertically. Has anyone ever done this before ?
__________________
Ka7niq
http://www.saferoofcleaning.com

  #2   Report Post  
Old March 6th 11, 03:10 PM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Aug 2006
Posts: 572
Default Trap Vertical Antenna Questions

On Mar 5, 9:25*am, ka7niq wrote:
I got to thinking WHY not take a hustler vertical
with only ONE *Tuned "radial" for each band ...


You are trusting that each radial will be resonant on only one band
akin to a fan vertical antenna. What may happen, for instance, is that
the 40m radial may accept an appreciable amount of energy on 15m and
direct the 15m signal up at a high take-off-angle - less than optimal
for 15m operation. Other interactions are possible, e.g. 28MHz/4MHz=7,
18.14MHz/3.6MHz=5, etc. Any vertical radial resonant at 3/4WL, 5/4WL,
7/4WL, etc. will have a suboptimal effect on the take-off-angle.
--
73, Cecil, w5dxp.com
  #3   Report Post  
Old March 6th 11, 06:24 PM
Member
 
First recorded activity by RadioBanter: Feb 2011
Location: Tampa florida
Posts: 33
Default

Quote:
Originally Posted by Cecil Moore View Post
On Mar 5, 9:25*am, ka7niq wrote:
I got to thinking WHY not take a hustler vertical
with only ONE *Tuned "radial" for each band ...


You are trusting that each radial will be resonant on only one band
akin to a fan vertical antenna. What may happen, for instance, is that
the 40m radial may accept an appreciable amount of energy on 15m and
direct the 15m signal up at a high take-off-angle - less than optimal
for 15m operation. Other interactions are possible, e.g. 28MHz/4MHz=7,
18.14MHz/3.6MHz=5, etc. Any vertical radial resonant at 3/4WL, 5/4WL,
7/4WL, etc. will have a suboptimal effect on the take-off-angle.
--
73, Cecil, w5dxp.com
I never considered this Cecil. Would you think it better to use a wire trap dipole instead of the Hustler 4BTV
and hang it vertical in the tree ?
__________________
Ka7niq
http://www.saferoofcleaning.com
  #4   Report Post  
Old March 8th 11, 05:59 PM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Jul 2006
Posts: 625
Default Trap Vertical Antenna Questions

On Mar 6, 12:24*pm, ka7niq wrote:
Cecil Moore;735465 Wrote: On Mar 5, 9:25*am, ka7niq wrote:-
I got to thinking WHY not take a hustler vertical
with only ONE *Tuned "radial" for each band ...-


You are trusting that each radial will be resonant on only one band
akin to a fan vertical antenna. What may happen, for instance, is that
the 40m radial may accept an appreciable amount of energy on 15m and
direct the 15m signal up at a high take-off-angle - less than optimal
for 15m operation. Other interactions are possible, e.g. 28MHz/4MHz=7,
18.14MHz/3.6MHz=5, etc. Any vertical radial resonant at 3/4WL, 5/4WL,
7/4WL, etc. will have a suboptimal effect on the take-off-angle.
--
73, Cecil, w5dxp.com


I never considered this Cecil. Would you think it better to use a wire
trap dipole instead of the Hustler 4BTV
and hang it vertical in the tree ?

--
ka7niq


My experience with the Hustler 4BTV hasn't been good. Over two hamfest
I bought 4 of them, lucky for me I was only buying then for the tubing
and mount and paid around $10 each for them. I dont think any of them
had a trap that wasnt bad.

Jimmie
  #5   Report Post  
Old March 8th 11, 06:19 PM
Member
 
First recorded activity by RadioBanter: Feb 2011
Location: Tampa florida
Posts: 33
Default

Quote:
Originally Posted by JIMMIE View Post
On Mar 6, 12:24*pm, ka7niq wrote:
Cecil Moore;735465 Wrote: On Mar 5, 9:25*am, ka7niq wrote:-
I got to thinking WHY not take a hustler vertical
with only ONE *Tuned "radial" for each band ...-


You are trusting that each radial will be resonant on only one band
akin to a fan vertical antenna. What may happen, for instance, is that
the 40m radial may accept an appreciable amount of energy on 15m and
direct the 15m signal up at a high take-off-angle - less than optimal
for 15m operation. Other interactions are possible, e.g. 28MHz/4MHz=7,
18.14MHz/3.6MHz=5, etc. Any vertical radial resonant at 3/4WL, 5/4WL,
7/4WL, etc. will have a suboptimal effect on the take-off-angle.
--
73, Cecil, w5dxp.com


I never considered this Cecil. Would you think it better to use a wire
trap dipole instead of the Hustler 4BTV
and hang it vertical in the tree ?

--
ka7niq


My experience with the Hustler 4BTV hasn't been good. Over two hamfest
I bought 4 of them, lucky for me I was only buying then for the tubing
and mount and paid around $10 each for them. I dont think any of them
had a trap that wasnt bad.

Jimmie
I have decided against the use of the Hustler 4BTV. I am going to buy a CB antenna for use on 17 through 10 meters, keep the feed line short, and use it with a tuner. I have been reading that several Hams are doing exactly this with the Antron 99 and Sirio Gain Master CB antennas, with decent results. I do plan on a self supporting tower one day, but this will get me on the air, until then.
__________________
Ka7niq
http://www.saferoofcleaning.com


  #6   Report Post  
Old March 8th 11, 06:21 PM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Mar 2007
Posts: 801
Default Trap Vertical Antenna Questions

JIMMIE wrote:


My experience with the Hustler 4BTV hasn't been good. Over two hamfest
I bought 4 of them, lucky for me I was only buying then for the tubing
and mount and paid around $10 each for them. I dont think any of them
had a trap that wasnt bad.

Maybe the bad traps were why they were only $10?


  #7   Report Post  
Old March 8th 11, 07:13 PM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Mar 2008
Posts: 329
Default Trap Vertical Antenna Questions

On 5 mar, 16:25, ka7niq wrote:
I have a tree here in the Tampa Florida area just begging to have a
Hustler 4 or 5 BTV stuck in it. I have had great luck with ground
mounted Hustler Verticals when I lived near the sal****er of Tampa Bay.
I am now in Brandon Florida, east of Tampa, and far from salt water. I
have stuck Hustler Verticals in trees before with radials for most
bands, but had access to a bucket truck back then, and did not have
stents in my heart. I got to thinking WHY not take a hustler vertical
with only ONE *Tuned "radial" for each band in the form of the lower
part of a 1/2 wave dipole. In other words, make the Hustler Vertical
into a multi band center fed 1/2 wave dipole. It will be a lot easier to
deal with only one radial for each band if they hang straight down the
tree vertically. Has anyone ever done this before ?

--
ka7niq


Hello Chris,

From another thread I concluded you have a flat membrane roof.

If you plan to use the 80/75m antenna for NVIS (local traffic) mostly,
why not putting a horizontal dipole above your roof. It will be very
likely below resonance length, but you can match this to 50 Ohms. This
will almost certainly result in better efficiency w.r.t. the
commercial vertical. For 40m and below, you can go vertical.

If you like to experiment and know the problems w.r.t. RF high
voltage, you may try a vertical resonating antenna that is in half
wave resonance. You will get end-fed voltages in the kV range, but the
common mode current will be significantly less w.r.t. a quarter wave
resonating structure. This reduces the requirements for your ground
provision and the ground loss.

What is the height of the tree that you plan to use as support (in
other words what is the maximum vertical height you can use)?

With kind regards,


Wim
PA3DJS
www.tetech.nl
  #8   Report Post  
Old March 9th 11, 01:07 AM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Mar 2007
Posts: 801
Default Trap Vertical Antenna Questions

ka7niq wrote:
JIMMIE;735930 Wrote:
On Mar 6, 12:24*pm, ka7niq wrote:-
Cecil Moore;735465 Wrote: On Mar 5, 9:25*am, ka7niq
wrote:--
I got to thinking WHY not take a hustler vertical
with only ONE *Tuned "radial" for each band ...--
-
You are trusting that each radial will be resonant on only one band
akin to a fan vertical antenna. What may happen, for instance, is
that
the 40m radial may accept an appreciable amount of energy on 15m and
direct the 15m signal up at a high take-off-angle - less than optimal
for 15m operation. Other interactions are possible, e.g.
28MHz/4MHz=7,
18.14MHz/3.6MHz=5, etc. Any vertical radial resonant at 3/4WL, 5/4WL,
7/4WL, etc. will have a suboptimal effect on the take-off-angle.
--
73, Cecil, w5dxp.com-

I never considered this Cecil. Would you think it better to use a wire
trap dipole instead of the Hustler 4BTV
and hang it vertical in the tree ?

--
ka7niq-

My experience with the Hustler 4BTV hasn't been good. Over two hamfest
I bought 4 of them, lucky for me I was only buying then for the tubing
and mount and paid around $10 each for them. I dont think any of them
had a trap that wasnt bad.

Jimmie I have decided against the use of the Hustler 4BTV. I am going to buy a

CB antenna for use on 17 through 10 meters, keep the feed line short,
and use it with a tuner. I have been reading that several Hams are doing
exactly this with the Antron 99 and Sirio Gain Master CB antennas, with
decent results. I do plan on a self supporting tower one day, but this
will get me on the air, until then.


If you put an autotuner at the base of a 1/4 wave 10m vertical (i.e.
2.5m long), and some random length radials, for 10,12,15,17, and 20, it
will work fairly well.

The feedpoint impedance of a half length antenna (i.e. 1/8 wavelength
vertical) isn't so horribly different that losses will bite you.
(for comparison.. I ran some models a while ago for a 20-odd foot
vertical. resonant (Z=39 ohms) at 9.4 MHz, and at 4.7 MHz, the z was
14-271j. I just happened to have that data handy.. you're looking at a
shorter antenna and higher frequencies, but the ratios are likely to be
similar.

W9CF's tuner calculator says a T network for the first case (Z=39 at
9.4MHz) would have 0.1 dB loss (3%), and for the second case, you'd have
1.7dB loss (33%)

While it's not great to burn a third of your power in tuner/feedline
losses, on the other hand, it's also not horrible.

If you can put up something that's around 3-4 meters (10-13 feet) long,
that will work even better. A piece of plastic pipe with some 12gauge
wire inside it, for instance. or a 10 foot length of thinwall 1/2"
conduit (sure, it's steel, but it's also got pretty good surface area..
without actually doing the calculation, it's probably comparable to a
12AWG wire in resistance)
  #9   Report Post  
Old March 9th 11, 01:13 AM
Member
 
First recorded activity by RadioBanter: Feb 2011
Location: Tampa florida
Posts: 33
Default

Quote:
Originally Posted by Wimpie[_2_] View Post
On 5 mar, 16:25, ka7niq wrote:
I have a tree here in the Tampa Florida area just begging to have a
Hustler 4 or 5 BTV stuck in it. I have had great luck with ground
mounted Hustler Verticals when I lived near the sal****er of Tampa Bay.
I am now in Brandon Florida, east of Tampa, and far from salt water. I
have stuck Hustler Verticals in trees before with radials for most
bands, but had access to a bucket truck back then, and did not have
stents in my heart. I got to thinking WHY not take a hustler vertical
with only ONE *Tuned "radial" for each band in the form of the lower
part of a 1/2 wave dipole. In other words, make the Hustler Vertical
into a multi band center fed 1/2 wave dipole. It will be a lot easier to
deal with only one radial for each band if they hang straight down the
tree vertically. Has anyone ever done this before ?

--
ka7niq


Hello Chris,

From another thread I concluded you have a flat membrane roof.

If you plan to use the 80/75m antenna for NVIS (local traffic) mostly,
why not putting a horizontal dipole above your roof. It will be very
likely below resonance length, but you can match this to 50 Ohms. This
will almost certainly result in better efficiency w.r.t. the
commercial vertical. For 40m and below, you can go vertical.

If you like to experiment and know the problems w.r.t. RF high
voltage, you may try a vertical resonating antenna that is in half
wave resonance. You will get end-fed voltages in the kV range, but the
common mode current will be significantly less w.r.t. a quarter wave
resonating structure. This reduces the requirements for your ground
provision and the ground loss.

What is the height of the tree that you plan to use as support (in
other words what is the maximum vertical height you can use)?

With kind regards,


Wim
PA3DJS
www.tetech.nl
The Tree is about 40 feet tall, and yes I do have a flat roof. I could attach a sloping wire from the tree to the roof, and center feed it with ladder line. This wire would be about 60 to 80 feet long, give and take a little. Unfortunately, it will be very visible!
__________________
Ka7niq
http://www.saferoofcleaning.com
  #10   Report Post  
Old March 9th 11, 03:05 PM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Mar 2008
Posts: 329
Default Trap Vertical Antenna Questions

On 9 mar, 01:13, ka7niq wrote:
'Wimpie[_2_ Wrote:



;735960']On 5 mar, 16:25, ka7niq wrote:-
I have a tree here in the Tampa Florida area just begging to have a
Hustler 4 or 5 BTV stuck in it. I have had great luck with ground
mounted Hustler Verticals when I lived near the sal****er of Tampa
Bay.
I am now in Brandon Florida, east of Tampa, and far from salt water. I
have stuck Hustler Verticals in trees before with radials for most
bands, but had access to a bucket truck back then, and did not have
stents in my heart. I got to thinking WHY not take a hustler vertical
with only ONE *Tuned "radial" for each band in the form of the lower
part of a 1/2 wave dipole. In other words, make the Hustler Vertical
into a multi band center fed 1/2 wave dipole. It will be a lot easier
to
deal with only one radial for each band if they hang straight down the
tree vertically. Has anyone ever done this before ?


--
ka7niq-


Hello Chris,


From another thread I concluded you have a flat membrane roof.


If you plan to use the 80/75m antenna for NVIS (local traffic) mostly,
why not putting a horizontal dipole above your roof. It will be very
likely below resonance length, but you can match this to 50 Ohms. This
will almost certainly result in better efficiency w.r.t. the
commercial vertical. For 40m and below, you can go vertical.


If you like to experiment and know the problems w.r.t. RF high
voltage, you may try a vertical resonating antenna that is in half
wave resonance. You will get end-fed voltages in the kV range, but the
common mode current will be significantly less w.r.t. a quarter wave
resonating structure. This reduces the requirements for your ground
provision and the ground loss.


What is the height of the tree that you plan to use as support (in
other words what is the maximum vertical height you can use)?


With kind regards,


Wim
PA3DJS
www.tetech.nl


The *Tree is about 40 feet tall, and yes I do have a flat roof. I could
attach a sloping wire from the tree to the roof, and center feed it with
ladder line. This wire would be about 60 to 80 feet long, give and take
a little. Unfortunately, it will be very visible!

--
ka7niq


Hello Chris,

My idea is/was to have the (short) 75/80m dipole above your roof
(assuming that the roof supporting structure isn't conducting). When
you put the matching components and balun function in a box on the
roof, you can go down with just a coaxial cable. This will keep the
VSWR within acceptable limits to allow further matching in the shack.
If space/visibility permits, I would go for the ladder line as you
suggested. Main disadvantage of the dipole above the roof:
interference from and towards domestic equipment.

When the visibility of the dipole above the roof meets aesthetic rules
by far, you may put 2 or more wires to the dipole (fan type short
dipole). This reduces the reactive component, without reducing the
radiation resistance, so matching becomes easier. Visibility, is this
really a problem?

Given the size of the tree, 40m and below should be possible without
huge investment in ground provision. For 10m the wire/tube length
isn't good, unless you can add a reactance to get collinear
behavior.

The above doesn’t mean 80m isn't possible, but due to the low
radiation resistance (about 5 Ohms), you need a better counterpoise /
ground provision, and the NVIS performance of your vertical isn't
good.

As with many things, making a choice isn't easy. A tree 60..80 feet
from your house looks very attractive from an interference
perspective.

With kind regards,

Wim
PA3DJS
www.tetech.nl


Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Swan 1040 V Trap Vertical [email protected] Antenna 0 August 27th 08 12:39 AM
dc grounding on 25ft trap vertical ant 10m-80m DAVID BROWNE Antenna 11 January 2nd 05 08:18 PM
HUSTLER TRAP VERTICAL Stuart Cole General 1 August 22nd 04 03:42 PM
HUSTLER TRAP VERTICAL MANUAL Stuart Cole Equipment 0 August 22nd 04 01:10 PM
HUSTLER TRAP VERTICAL MANUAL Stuart Cole Equipment 0 August 22nd 04 01:10 PM


All times are GMT +1. The time now is 05:22 AM.

Powered by vBulletin® Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.
Copyright ©2004-2021 RadioBanter.
The comments are property of their posters.
 

About Us

"It's about Radio"

 

Copyright © 2017