1. 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?

Discussion in 'CB Antennas' started by nosepc, Oct 6, 2013.

  1. nosepc

    nosepc
    Expand Collapse
    On Vacation

    Joined:
    Apr 12, 2013
    Messages:
    187
    Likes Received:
    7
    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.



    (y)(y)(y)(y)

    [​IMG]

    [​IMG]

    more than 8dbi (y)


    woww (y)

    [​IMG]
     

  2. HomerBB

    HomerBB
    Expand Collapse
    Sr. Member

    Joined:
    Jan 4, 2009
    Messages:
    2,863
    Likes Received:
    613
    I do like the Astroplane.
     
  3. radiodawg259

    radiodawg259
    Expand Collapse
    Member

    Joined:
    Oct 27, 2008
    Messages:
    51
    Likes Received:
    2
    Astroplane

    Astroplane what more can one say......
     
  4. basstracker1970

    basstracker1970
    Expand Collapse
    Active Member

    Joined:
    Nov 6, 2012
    Messages:
    156
    Likes Received:
    22
    Where can you buy one ? Do they still make these ?
     
  5. basstracker1970

    basstracker1970
    Expand Collapse
    Active Member

    Joined:
    Nov 6, 2012
    Messages:
    156
    Likes Received:
    22
    Bump
     
  6. Marconi

    Marconi
    Expand Collapse
    Usually if I can hear em' I can talk to em'.

    Joined:
    Oct 23, 2005
    Messages:
    5,441
    Likes Received:
    585
    1970, check both Coopers, maybe cheaper, and H&Y. Do a Google search.

    IMO you won't be sorry...if you get this one up to about 40' feet and make sure every thing is nice and tight. (y) <gotproof>
     
    2 people like this.
  7. ghz24

    ghz24
    Expand Collapse
    Member

    Joined:
    Mar 19, 2012
    Messages:
    75
    Likes Received:
    10
    perfect ground?

    8 dBi ?(looks like 7.87 to me) Could be because astroplane is a little directional.
    Perfect ground inflates gain and hides the take off angle.
    I have a dipole model at tip height of 36.25 ft , perfect ground gives it a gain of 8.04 dBi
    Freespace gives the well known 2.15dBi
    What height is the tip of your model at ?

    Not saying that some model of the astroplane wont show better gain (or TOA) than a dipole but what you posted doesn't seem to.

    Here is an adjustable astroplane model If anyone is interested in playing with it
    Code:
    CM 11 meter cb by ghz24
    CE
    SY z=62.85974	'driven element length
    SY rh=-86.8202	'ring height
    SY zp=6.972382	'feed gap
    SY rsf=0.413083	'changes ring diameter
    SY ch=9.221404	'capacitance hat length
    SY ml=-200	''mast length
    SY pph=rh+(rh*-0.5)	'pinch point height
    SY psf=0.97498
    SY ppy=(30*rsf-zp)*psf
    GW	1	1	0	0	0	0	-zp	0	0.48
    GW	2	67	0	0	0	0	0	ml	0.75
    GW	3	1	0	0	0	0	zp	0	.5
    GW	4	7	0	zp	0	0	ppy	pph	.25
    GW	5	7	0	-zp	0	0	-ppy	pph	.25
    GW	6	7	0	ppy	pph	0	30*rsf	rh	0.25
    GW	7	7	0	-ppy	pph	0	-30*rsf	rh	0.25
    GW	8	9	0	zp	0	0	zp	z	0.25
    GW	9	1	0	zp	z	0	zp+ch	z	0.25
    GW	10	1	0	zp	z	ch	zp	z	0.25
    GW	11	1	0	zp-ch	z	0	zp	z	0.25
    GW	12	1	0	zp	z	-ch	zp	z	0.25
    GW	100	1	29.99994*rsf	0*rsf	0+rh	27.7163225*rsf	11.4804889*rsf	0+rh	0.25
    GW	101	1	27.7163225*rsf	11.4804889*rsf	0+rh	21.2131466*rsf	21.2131466*rsf	0+rh	0.25
    GW	102	1	21.2131466*rsf	21.2131466*rsf	0+rh	11.4804889*rsf	27.7163225*rsf	0+rh	0.25
    GW	103	1	11.4804889*rsf	27.7163225*rsf	0+rh	0*rsf	29.99994*rsf	0+rh	0.25
    GW	104	1	0*rsf	29.99994*rsf	0+rh	-11.480489*rsf	27.7163225*rsf	0+rh	0.25
    GW	105	1	-11.480489*rsf	27.7163225*rsf	0+rh	-21.213147*rsf	21.2131466*rsf	0+rh	0.25
    GW	106	1	-21.213147*rsf	21.2131466*rsf	0+rh	-27.716323*rsf	11.4804889*rsf	0+rh	0.25
    GW	107	1	-27.716323*rsf	11.4804889*rsf	0+rh	-29.99994*rsf	0*rsf	0+rh	0.25
    GW	108	1	-29.99994*rsf	0*rsf	0+rh	-27.716323*rsf	-11.480489*rsf	0+rh	0.25
    GW	109	1	-27.716323*rsf	-11.480489*rsf	0+rh	-21.213147*rsf	-21.213147*rsf	0+rh	0.25
    GW	110	1	-21.213147*rsf	-21.213147*rsf	0+rh	-11.480489*rsf	-27.716323*rsf	0+rh	0.25
    GW	111	1	-11.480489*rsf	-27.716323*rsf	0+rh	0*rsf	-29.99994*rsf	0+rh	0.25
    GW	112	1	0*rsf	-29.99994*rsf	0+rh	11.4804889*rsf	-27.716323*rsf	0+rh	0.25
    GW	113	1	11.4804889*rsf	-27.716323*rsf	0+rh	21.2131466*rsf	-21.213147*rsf	0+rh	0.25
    GW	114	1	21.2131466*rsf	-21.213147*rsf	0+rh	27.7163225*rsf	-11.480489*rsf	0+rh	0.25
    GW	115	1	27.7163225*rsf	-11.480489*rsf	0+rh	29.99994*rsf	0*rsf	0+rh	0.25
    GS	0	0	0.0254
    GE	0
    GN	-1
    EK
    EX	0	1	1	0	1	0	0
    FR	0	0	0	0	27.18	0
    EN
    
    It may not be to the original dimensions of the AP but it can be easily altered using the variables.
    This one shows a gain increase over a dipole, only a little but its there .
    How about a peek at yours?
     
  8. hotrod

    hotrod
    Expand Collapse
    Well-Known Member

    Joined:
    Feb 16, 2007
    Messages:
    2,322
    Likes Received:
    167
    very nice!!!! where ya find this
     
  9. Shockwave

    Shockwave
    Expand Collapse
    Sr. Member

    Joined:
    Sep 19, 2009
    Messages:
    2,540
    Likes Received:
    759
    While the Astroplane is a good antenna for its compact size make no mistake, it has 0 dbd. It's a 1/4 wave ground plane with a free space gain of 2.15 dbi. Exactly the same as a unity gain dipole.
     
    arkoon likes this.
  10. basstracker1970

    basstracker1970
    Expand Collapse
    Active Member

    Joined:
    Nov 6, 2012
    Messages:
    156
    Likes Received:
    22
    How would this astroplane compare to the super penetrator 500 antenna?
     
  11. Shockwave

    Shockwave
    Expand Collapse
    Sr. Member

    Joined:
    Sep 19, 2009
    Messages:
    2,540
    Likes Received:
    759
    The gain of the 5/8 wave ground plane is heavily dependant on the ground plane under the vertical radiator. The radials on this antenna are far from an infinite ground plane but it is likely that the Penetrator would produce slightly stronger signals in the distance. The difference would not be noticed locally in most cases.

    This assumes both antenna would be mounted at the same height. If you could get the Astroplane up significantly higher than the larger Penetrator, then in would likely be the winner all around. If you want a vertical with enough gain to see a noticeable difference, you'll need something like a Gain Master or Vector 4000.
     
    1 person likes this.
  12. KC9Q

    KC9Q
    Expand Collapse
    Supporting Member

    Joined:
    Jan 14, 2012
    Messages:
    257
    Likes Received:
    58
    I looked up my old ASTRO Plane manual which states gain as 4.46 dBi. The ASTRO Plane is a shortened J-Pole antenna. No more; No less.
     
  13. Shockwave

    Shockwave
    Expand Collapse
    Sr. Member

    Joined:
    Sep 19, 2009
    Messages:
    2,540
    Likes Received:
    759
    Avanti lied. No way a 1/4 wave ground plane can produce anything more than 2.15 dbi. Check out the Sirio specs, they tell the truth and place it right at unity gain. Avanti also gave the Sigma a 6.14 dbi rating. Seems like their standard gain figures just added about 2 extra db onto everything.
     
  14. bob85

    bob85
    Expand Collapse
    Supporting Member

    Joined:
    Mar 30, 2005
    Messages:
    2,741
    Likes Received:
    561
    donald, i agree the astroplane has about the same gain as a dipole but i would like to see an astroplane in cst,

    i see it as a hat loaded 1/2wave, an upside down modified j-pole/sleeve antenna

    i imagine it radiates the same way as i think the sleeve on a sigma4 radiates via common mode currents on the outside of the legs,

    down one leg across the hoop up the other leg is close to 5/8wave so antenna mode impedance will be pretty high with minimal current flowing in a 50ohm system,
    when you add the mast you form a 50ohm transmission-line in parallel with the antenna mode impedance of the 5/8wave loop where significant transmission-line mode current will flow,

    we know what happens whenever there is a phase or magnitude imbalance at the end of a transmission-line,

    i think the 1/2wave mast is to minimise antenna mode mast currents in the same way an open sleeve or j-pole with a 1/2wave radiator surrounded by a 1/4wave sleeve will have little current flowing in the portion of radiator above the sleeve,
    the antenna mode impedance of a 1/2wave is high and most of the current flows in transmission-line mode in the lower 1/4wave,

    i will likely never find out if im right about the astroplane without a cst model since the avanti guys said to my great surprise in a magazine article that they did not understand exactly how it works.
     
  15. Shockwave

    Shockwave
    Expand Collapse
    Sr. Member

    Joined:
    Sep 19, 2009
    Messages:
    2,540
    Likes Received:
    759
    I will admit this antenna did surprise me a little bit when I put one into service many years ago. I've also heard many people say it worked like a 5/8 wave radiator. The part that downgrades my rating of the antenna is that Sirio is calling it a 1/4 wave ground plane at 2.15 dbi.

    I don't put too much weight on the name they call it but the gain figure has some merit to me because they seem spot on with every one of their other omni antennas. I suspect they have used CST on most of their antennas. I also think they choose to share that marketing info on the antennas they have the biggest investments in.

    Sooner or later I think CST will become more popular and we will find someone willing to test some of these ideas. With respect to Avanti, it's not hard for me to believe these guys got lucky a few times just bending radials in the field and stumbled into this effect by accident. At no time did Avanti even attempt to explain how the Sigma or Astroplane worked. Not a hint in the patents either.

    I think you got the truth in the CB magazine article about the Astroplane and probably would have gotten the same answer for the Sigma. Except certain people that worked for the company still can't admit they didn't have a clue on how the Sigma worked.

    One still claims Herb just made it because it looked cool. You would think these guys could look at the CST model today and figure it out....but no. Still in the dark just like the first day it went into production. I guess it's better to make something that works and not know why than to make something that doesn't and not know why.
     
    1 person likes this.

Share This Page