-
You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
ASTROPLANE best vertical antenna ever?
- Thread starter nosepc
- Start date
Hello Harry,
I can only tell you my experiences with noise, and over a long time on the CB, I see exactly what you describe hearing noise on your GM, it varies from time to time. Alexis tells us, he is in the same boat.
I really appreciate folks that try and mitigate noise, and I hear some really good ideas that are reported producing good results.
IMO, my Gain Master showed me the best example of mitigating common model currents using a choke, bar none, even though I have little experience in noise suppression management.
My antenna modeling has demonstrated Common Mode Currents to me over and over. So, I don't think you can buy, out of the box, a better example of a very good CMC choking setup, than the Gain Master. Plus it always worked exceptionally good for me.
Now, I have also done some old corny videos comparing some of my antennas...as I was comparing the signals only. But I can still look back at these old videos (see link to my Youtube folder in my signature below) and sometimes see that I had other antennas I was comparing to the GM, that showed <>1 Sunit less noise...when no signals were were being transmitted in my area at the time.
So, I've also seen the opposite results at times, so IMP this experience was not always consistent over time for me.
IMO, overall I think the Gain Master was the best all around antenna I ever bought...right out of the box.
BTW, going backwards in performance is not always the worst thing to consider, I think giving up a little gain to get an improvement in receiving can be a big plus.
Last edited:
Marconi,
Thank you for the info. Is there any truth that aluminum/metal antennas have less "white noise" than fiberglass antennas? I run a Yaesu that is very good on receive and I can filter down the static but I just hate to not give the new Targa/Astroplane a try for old time sake.
Thank you for the info. Is there any truth that aluminum/metal antennas have less "white noise" than fiberglass antennas? I run a Yaesu that is very good on receive and I can filter down the static but I just hate to not give the new Targa/Astroplane a try for old time sake.
Good question:
The only experience I remember is getting a mild shock in the winter time, mostly as I walked across a synthetic fiber rug in my bare feet and got a spark on touching the metal door knob.
So Harry, if that qualifies as a reliable source of info...maybe static on a fiberglass tubes, supporting a wire radiator inside, is possibly some reliable information. Probably has been used to support the countless stories we've hear about FG antennas being a notorious static and TVI problem, and worse being described as a bad dummy load.
My circle of old radio buddies use to refer to noise on their receivers as "bad conditions," and that is a pretty broad description. Signals going up and down in strength and volume, were said to be the "the band is stretching or stretching-out."
I don't know the science, but I'm sure someone will have the answer soon. I've heard what is sometimes referred to as white noise, but I'm not sure I know what causes it, but again...I'm sure somebody will have and answer shortly.
I tended to believe much of this type of wisdom until I got my Gain Master.
IMO, the AstroPlane produces a pattern very similar to a center fed 1/2 wave dipole, and the currents on my models shows a pattern like a 1/2 wave, but some call is a 5/8 wave antenna and the box is said to have 5/8 wave on the shipping container...so it's whatever.
I can turn the Free Space model I use for the A/P upside down and it looks very similar to a 3/4 wave Sirio New Vector 4000, if I extend the mast inside of the bottom radial area to 3/4 instead of a 1/2 wave...so folks in CB call it a lots of things, but in business the advertising descriptions probably rule and puffing is the old name for what they do to promote products.
It is sorta' like you kids...you can name them whatever you like.
Below are some antenna pattern overlays for a little comparison.
I can turn the Free Space model I use for the A/P upside down and it looks very similar to a 3/4 wave Sirio New Vector 4000, if I extend the mast inside of the bottom radial area to 3/4 instead of a 1/2 wave...so folks in CB call it a lots of things, but in business the advertising descriptions probably rule and puffing is the old name for what they do to promote products.
It is sorta' like you kids...you can name them whatever you like.
Below are some antenna pattern overlays for a little comparison.
Last edited:
Harry, that is good question.
Here is my suggestion.
I set my models length for the antenna mast at 192" - 197" x 1..50" inches and extend this mast form the mounting hub and down <> 1/4 wavelength below the loop...at the bottom of the antenna.This will get you close to a 1/2 wavelength overall, considering the diameters in play here.
Then at this point I make a 2" inch isolation, a non conductive space in my models. Then I add the supporting mast below this point, down to the Earth with another pipe also at 1.50" inches in diameter.
I then add a choking device or Isolater for the feed line at this same point. The idea here is to isolate the feed line and the supporting mast from the antenna currents, and minimize the currents on the antenna mast inside the radials and below as much as possible. In this case, another good man on this forum The DB as found that making his models with this antenna mast length set at 220" inches long...instead of the 197" inches like I use, lowers the currents on the antenna mast even more, and that is good.
These ideas have, more or less, been proven to benefit this antenna pattern, the gain and angle of the pattern, the match can also be effected. IMO, the main benefit for this setup idea is helping to eliminate antenna noise from getting into your receiver.
Such results may be found to be amazing, when you can hear weak signals as your CB buddies around you are complaining about too much noise and they can only hear the biggest signals on their receiver.
Harry, my stuff above is relative more toward modeling, but Bob85 is the man to ask about more details regarding the real world results.
So, ask away.
Thanks Harry, but what you say is just a sign of the times...and it happens...just like you say.
Iron is a poor conductor. Conductivity is the ability of a material to propagate (force vectors of dielectric discharge) an electric current. Steel, including the range of grades known as stainless vary between 3% - 15% conductivity when referenced to copper at 100%. Aluminum comes in at 45 - 61%. See the chart posted further down the page.This is my ASTROPLANE copy avanti AV-101, ALL manufactured in IRON.
I get better signal than a dipole, a loop and a slim-jim.
more than 8dbi
woww
Iron has extremely poor conductivity.
Ranking Metal % Conductivity*
1 Silver (Pure) 105%
2 Copper 100%
3 Gold (Pure) 70%
4 Aluminum 61%
5 Brass 28%
6 Zinc 27%
7 Nickel 22%
8 Iron (Pure) 17%
9 Tin 15%
10 Phosphor Bronze 15%
11 Steel (Stainless included) 3-15%
12 Lead (Pure) 7%
13 Nickel Aluminum Bronze 7%
Modelled using eznec4, with the av101 at a feedpoint height of 36 feet we see the following:
Slice Max Gain: 4.38 dBi @ an Elevation Angle of 31.0 degrees.
This is the highest gain seen from configurations at 18', 27' 32' and 36' feedpoint heights, installed in the usual fashion, on a conducting mast from ground level to the feedpoint. Lowest Elevation Angle occurs @ 18' and is 16.0 degrees with gain @ 2.80 dBi. Beginning at 27' we see a second lobe evolving at higher angles and reduced gain figures. At no height mentioned above do we see anything close to the advertised gain appearing at an elevation (takeoff) angle of 5 degrees as mentioned in the patent and depicted using the polar elevation chart shown in figure 7 of the patent.
In addition, both resonant and non-resonant levels of high and low current, both in phase and out of phase with regard to the antenna are seen flowing in the support structure at all four heights.
Slice Max Gain: 4.38 dBi @ an Elevation Angle of 31.0 degrees.
This is the highest gain seen from configurations at 18', 27' 32' and 36' feedpoint heights, installed in the usual fashion, on a conducting mast from ground level to the feedpoint. Lowest Elevation Angle occurs @ 18' and is 16.0 degrees with gain @ 2.80 dBi. Beginning at 27' we see a second lobe evolving at higher angles and reduced gain figures. At no height mentioned above do we see anything close to the advertised gain appearing at an elevation (takeoff) angle of 5 degrees as mentioned in the patent and depicted using the polar elevation chart shown in figure 7 of the patent.
In addition, both resonant and non-resonant levels of high and low current, both in phase and out of phase with regard to the antenna are seen flowing in the support structure at all four heights.
Last edited: