| Author |
Message |
    
Crackerjack
Intermediate Member
Username: Crackerjack
Post Number: 294
Registered: 7-2004
| | Posted on Friday, April 15, 2005 - 9:42 pm: | 
|
We have room for only one antenna at the office, so we have used a Skylab in order to get the best middle of the roan for local and distance. That and the Skylab seta a flat almost perfect SWR without adjustments or antenna tuners.
We may be replacing it due to some wind damage, not sure it is necessary, A radial came loose (probably just needs some love) -but it has us looking,
Our mast hits 30' to the top of the mast, or the bottom of the coax/Skylab connection.
I have read the articles that are posted in the archives, good literature and a real good review of the Imax 2000 (good work).
We are looking at the Top-One, and the Imax. I am afraid the that the Imax will be too tall with the base at 30' (will it require guy wires on the mast?) I am also concerned about the tuning of the antenna -the literature is unclear how easily that is accomplished without raising and lowering the antenna dozens of times.
Would the Top One really improve distance radiation with a base at 30'? 39; seems to be some kind of important point, but that is the tip of the mast.
Top One looks stable and less wind resistant to me.
What about it, weigh in, if you have used any of these and have experience.
|
Alsworld
Advanced Member
Username: Alsworld
Post Number: 904
Registered: 1-2002
| | Posted on Friday, April 15, 2005 - 11:40 pm: |
|
Crackerjack,
I have not used the Top One, so have no personal experience with it. I do have/use an IMAX 2000, and will give you the straight up answer from my perspective with relation to your setup there.
First off, I absolutely love the performance of this antenna! Incredible performance for the price. Hard to beat in that aspect.
Now for your application. The IMAX 2000 is extremely flexible, much like a fishing fly rod. When it's windy, it whips around quite a bit. With that, and it's length, there comes a leverage effect. It may strain your mount without guy wires (based on what you said).
Also, although super easy to tune, I have had to put up and take down my antenna numerous times to fine tune the SWR settings. Maybe I strive for perfection achieving the lowest possible SWR's and proper bell curve, but there was some adjustments from 10' to 30+' above ground. Your results may vary.
Although this may be the first time I have ever recommended against the IMAX, based on my understnding of what you are looking for, it would seem that maybe a stiffer (and less wind resistant) antenna may be preferable in this particular situation. I don't know if the Top One is/or is not the right one for you, but I think you have some legitimate points on why in this particular circumstance the IMAX 2000 may not be the antenna of choice.
If you could guy it, then yes I would definitely recommend the IMAX.
Some thoughts for you to consider.
Alsworld |
Crackerjack
Intermediate Member
Username: Crackerjack
Post Number: 295
Registered: 7-2004
| | Posted on Saturday, April 16, 2005 - 1:36 am: |
|
Alan:
That is what I wanted, an objective opinion. I will try to get a photo of the mast in the morning.
I really do feel good about mounting the Top One, without any added fear of mast damage.
I guess, the question is if it would be an improvement over the Skylab -distance wise, Especially the 130 miles into Mexico that we are striving to maintain -while maintaining decent local omni-directional capabilities.
Thanks.
|
Crackerjack
Intermediate Member
Username: Crackerjack
Post Number: 296
Registered: 7-2004
| | Posted on Saturday, April 16, 2005 - 12:37 pm: |
|
How useful is a Quad V or a 3/4 element beam for local mobile users to hit the base? |
Road_warrior
Intermediate Member
Username: Road_warrior
Post Number: 491
Registered: 7-2004
| | Posted on Saturday, April 16, 2005 - 3:46 pm: |
|
A Imax 2000 should outperform the Skylab,
Imax is a great performer.
I took my Imax straight out of box and
installed it, 1:1:1 Swrs and never had
to re-tune it as it always stayed the same.
This was for the 40 channel, above and
below talking. Distances above ground of
30 ft or better to feedpoint, Imax is the one.
I had my Imax 2000 36-38 ft to feed point
mounted against my house, there was 13
ft of 1 1/4" TV mast sticking above the
roof plus the antenna and it had to be guyed
as it swayed to much. I have used a Astro
Plane in the past, but, it was at a lower
height, it did good. At higher heights i
don't know how it would perform.
JIM/ PA/ CEF 375 |
Road_warrior
Intermediate Member
Username: Road_warrior
Post Number: 492
Registered: 7-2004
| | Posted on Saturday, April 16, 2005 - 3:54 pm: |
|
I found i have no trouble at all talking
with local mobiles from my 4 element beam.
Unless your trying to talk to more than
one mobile and they are all different
directions.
I don't think a V quad would be that good
for what you want. You need something that
will hit the ground harder.
Good Luck with whatever you decide!
JIM/ PA/ CEF 375 |
Crackerjack
Intermediate Member
Username: Crackerjack
Post Number: 301
Registered: 7-2004
| | Posted on Saturday, April 16, 2005 - 4:59 pm: |
|
Jim
Is your beam mounted vertical? |
Road_warrior
Intermediate Member
Username: Road_warrior
Post Number: 493
Registered: 7-2004
| | Posted on Saturday, April 16, 2005 - 7:57 pm: |
|
My beams has both Vertical and Horz.
Verticle i use for talking local long
distances.
Horz i use for DX talking.
Its best to have a directional
beam and also a good omni antenna.
JIM/ PA/ CEF 375
|
Crackerjack
Intermediate Member
Username: Crackerjack
Post Number: 302
Registered: 7-2004
| | Posted on Saturday, April 16, 2005 - 8:16 pm: |
|
Yea, back to two antennas.... But what is the best vhoice for one antenna, cover all needs compromise, could it be a Qgad V? |
Bigbob
Senior Member
Username: Bigbob
Post Number: 1821
Registered: 12-2001
| | Posted on Saturday, April 16, 2005 - 8:42 pm: |
|
As with all antennas the longer the radiator(omni) the better it will perform e.g. I-max 2000,the more radiators (directional,beam) the better it will perform,if you can find a PDL-2,you'll have a good compromise,a maco comet would be similar in performance and both are better choices than the maco V-quad as the v-quad is quite narrow banded on some applications and hard to tune out reactance.Bigbob |
Kid_vicious
Intermediate Member
Username: Kid_vicious
Post Number: 397
Registered: 9-2004
| | Posted on Saturday, April 16, 2005 - 8:56 pm: |
|
crackerjack, i think i can be of some help.
i just put my TOP ONE up on a 40' mast. it works worderfully up there!!! my SWR on CH.1 is 1.3
on CH.20 its 1.2, and on CH.40 its 1.1. it also requires NO tuning. this is the perfect antenna for your situation. IMO.
here are the things you should be concerned with.
the top one needs 8.5 feet of free space underneath the ring with no obstructions for it to work properly. you must have a good metal to metal connection on each of your mast sections. you must run the coax down the mast for at least 8.5 feet from the ring.
if you want to know more, check out my post entitled "top one at 44' to the tip"
matt |
Road_warrior
Intermediate Member
Username: Road_warrior
Post Number: 494
Registered: 7-2004
| | Posted on Saturday, April 16, 2005 - 9:06 pm: |
|
I had a V-Quad years ago and i did
not care for it.
Small beams that work good are:
Signal Engineering Superhawk (5' boom)
PDL-2 (5' boom) no longer made, but,
can be found on auction sites.
Maco 3 element (11' boom)
Or any larger Maco beam.
Good omni groundplanes are:
Imax 2000, Maco V-5/8 wave, I-10K.
JIM/ PA/ CEF 375
|
Crackerjack
Intermediate Member
Username: Crackerjack
Post Number: 303
Registered: 7-2004
| | Posted on Saturday, April 16, 2005 - 10:02 pm: |
|
Bob"
The dual polarity antennas -have two coax running to the antenna?
Are there switches that mix both signals or just a choice one/other at the switch?
Who makes the PDL-2? |
Mikefromms
Advanced Member
Username: Mikefromms
Post Number: 559
Registered: 6-2003
| | Posted on Saturday, April 16, 2005 - 10:54 pm: |
|
Imax with groundplane kit. You will not regret it. Use good coax.
mikefromms |
Crackerjack
Intermediate Member
Username: Crackerjack
Post Number: 305
Registered: 7-2004
| | Posted on Saturday, April 16, 2005 - 11:34 pm: |
|
I think that the Imax will cause me Zoning problems. |
Road_warrior
Intermediate Member
Username: Road_warrior
Post Number: 496
Registered: 7-2004
| | Posted on Saturday, April 16, 2005 - 11:38 pm: |
|
The Pdl-2 is no longer in production.
They were made my Antenna Speciallists.
New ones can still be found on auction
sites from time to time.
JIM/ PA/ CEF 375 |
Crackerjack
Intermediate Member
Username: Crackerjack
Post Number: 306
Registered: 7-2004
| | Posted on Saturday, April 16, 2005 - 11:53 pm: |
|
Tjamks..
Yjese Bi=Polar units may be the answer, with a small foorprint.
I will ask again..
The dual polarity antennas -have two coax running to the antenna?
Are there switches that mix both signals or just a choice one/other at the switch?
|
Tech291
Moderator
Username: Tech291
Post Number: 145
Registered: 11-2004
| | Posted on Sunday, April 17, 2005 - 12:32 am: |
|
Crackerjack,
all the dual polarity antennas i have used did require 2 runs of coax and a switchbox to select horizontal or vertical.the last one was a moonraker4 and had plans to construct a relay unit so i could run just 1 coax but ended up getting rid of it before that happened.You could use a cophase harness and get circular polarity which could be handy for dx but not much advantage on local work
tech291
CEF#291
kc8zpj |
Road_warrior
Intermediate Member
Username: Road_warrior
Post Number: 498
Registered: 7-2004
| | Posted on Sunday, April 17, 2005 - 12:34 am: |
|
Yes, dual polarity beams take 2
coaxs.
Usually just one or the other, but,
Copper does sell a switchbox that
you can run one/other or both at the
same time.
JIM/ PA/ CEF 375 |
Crackerjack
Intermediate Member
Username: Crackerjack
Post Number: 308
Registered: 7-2004
| | Posted on Sunday, April 17, 2005 - 2:56 am: |
|
Top One, Astroplane type antenna sold by Copper's pI am a little confused by rgw measurements mentioned in different articles.
I see from 4 feet to 15 feet mentioned in different places.
What is the distance from the top of the MAST mount to the tip Top.
Mount to the bottom?
Thanks/ |
Mikefromms
Advanced Member
Username: Mikefromms
Post Number: 561
Registered: 6-2003
| | Posted on Sunday, April 17, 2005 - 7:02 am: |
|
About 4 feet. The pole goes through the middle of the antenna leaving the 4 foot sticking that transmits. This antenna is a winner.
mikefromms |
Pig040
Advanced Member
Username: Pig040
Post Number: 762
Registered: 7-2003
| | Posted on Sunday, April 17, 2005 - 9:22 am: |
|
Dosy makes a nice switchbox that allows you to run verticle or horizontal, or both at the same time, I have had one for years, and it works well.
Rich |
Crackerjack
Intermediate Member
Username: Crackerjack
Post Number: 311
Registered: 7-2004
| | Posted on Sunday, April 17, 2005 - 9:24 am: |
|
mikefromms:
Thanks. Have you actually owned/used one of them as to be able to compare it to a former/latter antenna?
The numbers and advertisements have me leading in this direction. But I fail to see how the angle of radiation is "raised to a higher level" by its design.
It looks like the feedpoint is exactlty in the same place as my Starduster. Right at mast tip, or 30 feet in my case. That being the case, the Starduster (Skylab) would acrually radiate higher being that the entire antenna sits above the mast.
Looks that way to me, anyway,
That said, there would have to be much less wind resistance too. Good point, indeed. |
Road_warrior
Advanced Member
Username: Road_warrior
Post Number: 500
Registered: 7-2004
| | Posted on Sunday, April 17, 2005 - 11:42 am: |
|
The Top One looks like it is no longer
available from Coppers.
Stated in there Catalog.
JIM/ PA/ CEF 375 |
Tech808
Moderator
Username: Tech808
Post Number: 5569
Registered: 8-2002
| | Posted on Sunday, April 17, 2005 - 11:54 am: |
|
Road Warrior,
You are correct!
S80-00010 Top One Ground Plane Antenna
$ 49.99
UNIT NO LONGER AVAILABLE
Top One Ground Plane Antenna
Similar to the old Astro Plane antenna
10 Meter 26-30Mhz
2000 watt max power
Easy Assembly
Height : 11.5'
Top Radiation - This design results in increased range, fewer dead spots. This is especially important where installed height is limited. Radiates approximately 15' higher than most antennas which radiate at the bottom.
Lower Angle of Radiation - Your signal hugs the curvature of the earth instead of shooting your power up into the sky, which means greater distance than an ordinary omni-directional antenna.
INVENTORY
Number in stock: 0
Not accepting back orders for this product.
*** CURRENTLY OUT OF STOCK ***
Top One Ground Plane Antenna
Lon
Tech808
CEF808
Tech808 |
Bigbob
Senior Member
Username: Bigbob
Post Number: 1826
Registered: 12-2001
| | Posted on Monday, April 18, 2005 - 9:03 pm: |
|
The dual polarity antennas were derived from circular polarization antennas,the verticals driven in phase and the horizontals driven 90 degrees out of phase by one coax and a matching stub using a co-phase harness or this could be visa-versa,but I think I'm right,just in case anybody wondered |
Mikefromms
Advanced Member
Username: Mikefromms
Post Number: 566
Registered: 6-2003
| | Posted on Monday, April 18, 2005 - 9:39 pm: |
|
Out of production. That was a great antenna. Really does it's thing low to the ground and I suppose high off the ground too.
Crackerjack, I've owned just about every groundplane there is now and I'll tell you the AP is a good as is the Starduster and Imax (my favorite). The AP is supposed to be a 5/8's wave design and the starduster 1/4 wave. The AP will cover a farther distance.
mikefromms |
Kid_vicious
Intermediate Member
Username: Kid_vicious
Post Number: 408
Registered: 9-2004
| | Posted on Monday, April 18, 2005 - 10:15 pm: |
|
boy im glad i got one when i did!
i have one in the air on 40' of mast and i love it! great bandwidth, low noise, no bleedover, strong in the winds, high power handling.
they're great! check out my post on the upgrades i did on mine. i think if you buy this antenna you'll find that they help.
matt |
Crackerjack
Intermediate Member
Username: Crackerjack
Post Number: 321
Registered: 7-2004
| | Posted on Monday, April 18, 2005 - 11:05 pm: |
|
mikefromms: Thanks, I actually have the 5/8 Astroplane, I need to correct my profile.
So you think on the 30' mast, it will outperform a Top One?
I do get DX to all corners on the Continent, including Canada, Bahamas, Alaska once. O cam see a need/use for side/back rejection that I don't have, but the antenna is a good antenna. |
Crackerjack
Intermediate Member
Username: Crackerjack
Post Number: 323
Registered: 7-2004
| | Posted on Tuesday, April 19, 2005 - 8:51 am: |
|
I mis-spoke above, I meant say that I have a 5/8 STARDUSTER. |
