| Author |
Message |
    
Gonzo
Junior Member
Username: Gonzo
Post Number: 45
Registered: 9-2004
| | Posted on Wednesday, October 13, 2004 - 1:34 pm: | 
|
Well I just compared these two antennas today. They were both at the same height above the house, and fed by approxiamately the same amount of coax (same type). One on one side of house, the other 50 feet away on the other side, both grounded. Both antennas claim to be 5/8 wave. I always thought that the Astroplane claiming 5/8 wave was sort of a stretch.
And my testing today shows this to be true. In all cases with familiar local contacts (not skip)
The Imax 2000 out gunned the Astroplane by at least 1 1/2- 2 S-units. The SWR on both antennas was 1.2 to 1
Recieving with the Astroplane was also down 1-2 S units. Although the Imax 2000 is pretty good, it is by no means the best Omni out there, but it is apparently better than the Astroplane. At least from this location. |
Lazylizard
Junior Member
Username: Lazylizard
Post Number: 24
Registered: 2-2004
| | Posted on Thursday, October 14, 2004 - 11:09 am: |
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Well, then what is the best omni directional base antenna out there? |
Bruce
Senior Member
Username: Bruce
Post Number: 1670
Registered: 9-2003
| | Posted on Thursday, October 14, 2004 - 12:07 pm: |
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I used the TOP-ONE here and it worked well untill the last hurricane flatened it. If your room is limited its a good choice otherwise the imax has the edge. |
Gonzo
Member
Username: Gonzo
Post Number: 50
Registered: 9-2004
| | Posted on Thursday, October 14, 2004 - 4:30 pm: |
|
I would think a true 5/8 wave (22+ ft tall) aluminum antenna with 4 9ft ground radials should work better than almost anything else out there.
Imax2000 with ground radial kit is pretty good. But I know the omni I used to have a HyGain Penetrator 5/8 wave would be better.That even worked better then my Super Scanner in omni position.
However a big plus is that the Imax will certainly hold up better than the aluminum's to wind and SWR rain fluctuations.
Aluminum's:
MACO ALPHA V 5/8...relatively cheap and probably good
INTERCEPTOR-10K ....too expensive but an exact duplicate of the Hygain Penetrator, this would be the best aluminum me thinks.
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Keithinatlanta
Intermediate Member
Username: Keithinatlanta
Post Number: 401
Registered: 3-2003
| | Posted on Thursday, October 14, 2004 - 6:02 pm: |
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Hey Gonzo. Long live my old
Antenna Specialists Super Mag antenna. It was great back in the 70's. I talked all over Denver for local, and when skip was rolling, I went all over America. I ran a simple 23 channel Lafayette base station. NO power, NO amplifiers, just radio with D 104 mike. Yes, being a mile high helped for skip , but not local. Just a great antenna back in those days.
Keith in Atlanta
CEF 150 |
Bruce
Senior Member
Username: Bruce
Post Number: 1674
Registered: 9-2003
| | Posted on Thursday, October 14, 2004 - 7:03 pm: |
|
Gonzo
Don't undersell the top-one ( astro-plane ) it works well ....
A 5/8 wave will do better and is twice the size. Your supper scanner devided the signal between 3 antennas in omi mode so you had a net loss. Also the " Starduster " works well mine was fine untill lighting got it. |
Gonzo
Member
Username: Gonzo
Post Number: 51
Registered: 9-2004
| | Posted on Thursday, October 14, 2004 - 7:06 pm: |
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I might be wrong but the Maco Alpha V 5/8 wave antenna is only 16-20feet long and would be 5/8 wave on 10 meters only. So on CB band this would act as a 1/2 wave. |
Gonzo
Member
Username: Gonzo
Post Number: 52
Registered: 9-2004
| | Posted on Thursday, October 14, 2004 - 8:49 pm: |
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One thing I have learned about antennas. Capture area counts alot. 1/4 wave is 9 feet....a 9 foot whip makes the best mobile antenna period, anything shorter is a compromise.
1/2 wave is 18 feet, anything shorter will not work as well.
5/8 wave is 22 feet, anything shorter will not work as well, no matter how it is advertised.
The Astroplane is 11 feet, it is NOT a 5/8 wave radiator, and has only been advertised as such, since it has been called Top One. The old Astroplane made no such claim. What do you think gets out better 11 feet or the proper 22 feet or even 18 feet??
----------------------------
The Super Scanner in Omni mode is 3 elements Tri-phased as they call it. However it is the equilvalent I believe of one 1/2 wave dipole.
Similar in performance to a A-99
Each element is the proper 18 feet in lenght.
In beam mode it uses one element as the director and the other 2 elements as reflectors, sort of a 2 1/2 element beam.. An excellent space saving design, without the need of a rotor.
-----------------
I used to have a starduster also, it made claims of 5db gain at the time, which was similar to the HyGain Penetrator 5.1 db gain. The starduster is basically a 1/2 wave antenna, again similar to a A-99, except that the radials are not the coax, but extend down to near -75 degrees. Mine worked OK, but was no match for a proper 22 foot tall 5/8 radiator. The starduster in reality worked a little better than a shakespeare big stick, because it was aluminum, but other than that, there is nothing to be impressed about. |
Tech548
Moderator
Username: Tech548
Post Number: 316
Registered: 5-2004
| | Posted on Thursday, October 14, 2004 - 11:52 pm: |
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Good post Gonzo.
Looks like you have been doing your homework.
By the way, the I-Max is a 24 footer....not 22.
Jeff
Tech548
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Bruce
Senior Member
Username: Bruce
Post Number: 1676
Registered: 9-2003
| | Posted on Friday, October 15, 2004 - 5:28 am: |
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Hummmmm?
"Capture area counts alot. 1/4 wave is 9 feet....a 9 foot whip makes the best mobile antenna period, anything shorter is a compromise. "
Your mixing apples and oranges Capture area DOSE COUNT but it not why a 9 foot wip works better than a 2 foot one the reason is to make a 2 foot antenna work you have to LOAD it to look like a 9 foot one and that adds LOSSES. Now as for a astroplane it is a good antenna but I never said it would be a better antenna that a 5/8 wave only it DOES WORK WELL...... as does the starduster which has a fairly low angle of radiation. Your super scanner has LOSS in omi directional because your feeding 3 antennas at the same time ..... yes 1/2 wave dypoles. Now as for 5 db of gain it would take a 36 foot tall antenna to get 5 db of gain .... your 5/8 wave has some over that starduster but no 3 db. Your afixed on 5/8 waves and ive run then for the last 40 years my SHORT 2 meter moble wip is a 5/8 wave and the LONG one 7 foot is a 5 DB GAIN STICK. On 6 and 2 and 440 i run 5/8 wave antennas as omis there ok .....NO 5 DB GAIN .... some over a starduster .... o yes i had a 6 meter starduster and it also worked WELL. Now my big stick is 3 5/8 waves STACKED on 2 meters and 6 stacked on 440 now it DOES have about 7 db on 2 and about 9 on 440 ( DBI that is ). LAST WIVES TALE alumin works better than fiber glass .... realy humm??? well better go check out most of the high gain base antennas for VHF/UHF are like my big stick some have 12 5/8 waves or 1/2 waves STACKED all neatly packed in a fiberglass dome works just fine .....They dont use the glass for the antenna only to PACK IT o there is some loss in the glass but not worth worying about.
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Gonzo
Member
Username: Gonzo
Post Number: 53
Registered: 9-2004
| | Posted on Friday, October 15, 2004 - 8:33 am: |
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Slow down partner... I never said I believed the gain figures, I was just reporting what they were claimed as. I think we all are aware that gain claimed is in most cases false.
Here is the original question I was responding to "what is the best omni directional base antenna out there?"
Bottom line a full 5/8 wave 22+ feet tall and in Aluminum...would make the best Omni period. |
Tech808
Moderator
Username: Tech808
Post Number: 3830
Registered: 8-2002
| | Posted on Friday, October 15, 2004 - 9:05 am: |
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Hmmmmmmmm,
Maybe Tech833's Article he wrote here for the Copper Forum Members can be of help.
It is Located in the:
Subscriber (Preview) Area
» Articles
» How to Choose a Ground Plane Antenna
******
Copper Electronics Omni/Vertical Antenna Suggestion Guideby Tech833
When choosing an omnidirectional base station antenna, several choices are available. Predicting the performance of each one is simple in theoretical circumstances, but in actual use conditions, many external situations can change the expected performance conditions greatly. In the simplest terms, there is not one perfect antenna for all situations. Taking into account the 4 biggest concerns of consumers and applying them to this purchase, we base these suggestions on the following criteria: price, power handling capability, expected mounting height over ground, and high wind survival.
The antennas are listed under each category based on expected transmit and receive performance at a distance using ground wave propagation. The antenna with the highest expected performance under a certain condition will appear on top and the antenna fitting that category with the lowest expected level of performance will be on the bottom. Obviously, the transmit and receive performance will match very closely under various conditions, so the order in which the antennas are listed remains suitable for stations only wishing to transmit (such as a beacon station) or wishing to only receive (SWL).
10 meter amateur and high power stations-
(All of the antennas in this category will handle high winds and/or high power and have wide bandwidth.)
If the tip of the antenna will be less than 30 feet above ground:
CTE Top One
Maco V-5/8
If the tip of the antenna will be greater than 30 feet above ground:
Maco V-5/8
CTE Top One
11 meter only stations-
(All of the antennas in this category will handle high winds.)
If the tip of the antenna will be less than 30 feet above ground:
CTE Top One
Shakespeare Army Big Stick
Maco V-5/8
Imax 2000 w/GPK*
If the tip of the antenna will be greater than 30 feet above ground:
Maco V-5/8
Imax 2000 w/GPK**
Shakespeare Army Big Stick
Antron 99 or Imax 99***
CTE Top One
11 meter only stations on a budget (under $50)-
(The antennas in this category not appearing in categories above will not handle high winds and/or high power.)
If the tip of the antenna will be less than 30 feet above ground:
CTE Top One
If the tip of the antenna will be greater than 30 feet above ground:
Antron 99 or Imax 99
CTE Top One
Skylab T233
Stations in areas which experience winds over 90 MPH.-
CTE Top One****
| | | | A99 | A99
w/GPK | Sky
Lab
T233 | Imax
99 | Big
Stick | Imax
2000 | Imax
2000
w/GPK | Maco
V5/8 | CTE
Top
One | | | | 11 meter | • | • | • | • | • | • | • | • | • | | | | 10 Meter | | | | | | | | • | • | | | | High Power | | | | | | | | • | • | | | | High Wind | | | | | | | | • | • | | | | Above 30' | • | • | • | • | • | • | • | • | • | | | | Below 30' | | | | | • | | • | • | • | | | | Price Range | under $50 | under $100 | under $50 | under $50 | under $100 | under $100 | under $150 | under $100 | under $50 |
Notes:
* The GPK (Ground Plane Kit) can be substituted with at least 3 bonded metallic guy wires attached to the support mast immediately under the base of the antenna measuring at least 9 feet long each.
** If the GPK is not added, the performance will not be greater than the Shakespeare Army Big Stick.
*** Adding the GPK to either the Antron 99 or Imax 99 will not improve the performance enough to change the ranking in this category.
**** When the lower hoop element is braced to the support mast with non-metallic monofilament, rope or twine.
******
His article addresses about every question one may have.
Lon
Tech808 |
Wrk3
Junior Member
Username: Wrk3
Post Number: 30
Registered: 4-2004
| | Posted on Friday, October 15, 2004 - 3:39 pm: |
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where does Jay's I-10K, rank??? |
Gonzo
Member
Username: Gonzo
Post Number: 54
Registered: 9-2004
| | Posted on Friday, October 15, 2004 - 4:15 pm: |
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Read above: "INTERCEPTOR-10K ....too expensive but an exact duplicate of the Hygain Penetrator, this would be the best aluminum me thinks" |
Tech833
Member
Username: Tech833
Post Number: 50
Registered: 12-2001
| | Posted on Friday, October 15, 2004 - 6:43 pm: |
|
When this was written, the Imax was in its infancy. I had not yet tested the I-10K if I recall.
You should know, the Maco V-5/8 seems to have very slightly better performance than the I-10K antenna. The 'trombone tuning' network on the I-10K tends to send some signal straight down and distorts the field pattern slightly as well. The Maco V-5/8 tuning ring is not perfect, but it distorts the field pattern much less than the I-10K trombone tuning does. That translates to more signal on the horizon from the Maco. The Super Penetrator sealed coil matching network is slightly more lossy than the Maco or the I-10K, but it distorts the pattern much less. That loss is negligible, but it does limit the power handling capability to under 1 KW.
My complete review of the I-10K was never published at the request of the antenna maker who was kind enough to send the example for testing. If you plan to run power levels over 5 KW, or expose the antenna to 100 MPH+ winds, then the I-10K is a great choice. If you don't, the Maco V-5/8 will work better and is far less expensive.
Still, to this day, I would push the Imax 2000 for its ease of installation, stealthyness, and good performance. If stealth and ease of installation are of no concern to you, the Maco V-5/8 is almost impossible to beat. If you can't put up anything higher than 20-30 feet overall above ground, then the Top One is impossible to beat. |
Bruce
Senior Member
Username: Bruce
Post Number: 1679
Registered: 9-2003
| | Posted on Friday, October 15, 2004 - 7:37 pm: |
|
Ok
Gonzo, 808.......
My city requires you have a licensed engineer install and ceritfy your antenna will withstand 125 MPH winds.......... UNLESS
1) It is less that 35 foot to the TOP of the antenna ..... FROM THE GROUND !
2) It is mounted on a support less that 2 inches
BOTH MUST BE MEET this has been the law here for at least 25 years.
Now it took 4 hurricanes in a 2 months time to distroy the top one it with stood winds toping out at 100 MPH ! Offical winds here in Seminole were 90-100 and sustained 75.
That said a 23 foot tall 5/8 wave would meen the bottom would have to be even with my 50 *12 foot alumin roof not a good thing. The top one only being about 13 foot was mounted on 30 foot of mast allowing 1/2 wave from it to the main roof and it work FINE.
The starduster was cut to 52 MHZ and for almost 2 years did as well as a 5/8 wave endfeed antenna that i checked it against ...... it saved my Hustler 4 band vertical by taking a DIRECT LIGHTING hit that would have distroyed that $150 Hustler antenna .... YES the starduster was fried.
The 5/8 wave is a good antenna but so are others antennas they do well installed correctly ... and like here i cannot install any 5/8 wave except for the VHF/UHF bands. If i want gain i would take 2 astro planes and co-phase them ..... and still stay within the law. |
Road_warrior
Intermediate Member
Username: Road_warrior
Post Number: 116
Registered: 7-2004
| | Posted on Friday, October 15, 2004 - 8:13 pm: |
|
When i first got my I-10k Antenna,i put it
on my 40ft tower and ran it for a few days.
I then, put my imax 2000 on my tower at the
same height.The I-10k was 1 full db unit better
on transmit & recieve (locally). Plus, quieter.
Then, i put I-10k back on tower, 49ft to feedpoint.
I mounted my Imax 2000 to my house, 36ft to
feedpoint. With the skip thats been rolling
here in PA, the Imax 2000 out does the I-10k.
YES, even though the Imax is lower...
Right now I have my tower & I-10k down...(tower
getting painted) next time tower goes up, a
White Lightning will be on it...LOL
JIM/Road_warrior/CEF 375 |
Gonzo
Member
Username: Gonzo
Post Number: 55
Registered: 9-2004
| | Posted on Friday, October 15, 2004 - 9:18 pm: |
|
The Maco 5/8 wave is only 5/8 wave on 10 meters, not 11 meters if it is only 16-20feet tall. Please correct me if I am wrong on the lenght of this antenna. On 11 meters it is then a 1/2 wave. It reminds me of an antenna called a "Ringo" infact I believe it to be the same design. This was a 1/2 wave antenna.
I find it very hard to believe a "Ringo" or any 1/2 wave antenna would beat a well constructed and erected 5/8 wave Omni. I do not work for Copper or anyone else, and have no interest in either design.
-------------------------------
I do believe the STEALTH IMAX2000 to be a good antenna, and most practical of all of em'
-------------------------------
Road Warrior...with both antennas at the same height, the I-10K was best...yes?? Thats seems entirely possible. As to why a lower antenna at a different location would out-perform a higher one on skip, introduces alot of unknowns, and as Bruce said...if taken under the exact same conditions for both antennas..then and only then could the test be considered valid.
-----------------------
Bruce...I know you had a Starduster and have a Top One...they are both good, I had them both too. |
Road_warrior
Intermediate Member
Username: Road_warrior
Post Number: 118
Registered: 7-2004
| | Posted on Friday, October 15, 2004 - 10:56 pm: |
|
I have switched back & forth between Antennas
while shooting skip. For some reason the Imax
2000 at a lower height did better most of the time. I know conditions can change at any
given moment, but, that just the way it was...
Like Tech 833 said, I'd push an Imax 2000 for
its ease in installation, stealthyness & good
performance.
I also have a old Maco 5/8 wave Antenna. They are a good Antenna. But, i still like the Imax.
JIM/Road Warrior/CEF 375
|
Bruce
Senior Member
Username: Bruce
Post Number: 1680
Registered: 9-2003
| | Posted on Friday, October 15, 2004 - 11:26 pm: |
|
Gonzo
I have used ringos on 11 meters to 440 mhz ( 3/4 meters ) and found nothing wrong with them. Now the VHF/UHF ringo rangers are a good buy for the buck last a long time and i ve never had one go bad. Right now im using a ringo on 6 and a ranger on MURS both have been measured against a 2 nd antenna on 6 it was a DI-6 5/8 wave and on 2 meters a DI-2 also 5/8 wave. Mounted in the EXACT same spot gain on the DI-6 which is about 11 foot was about 1 db better on 2 meters the ranger was more than 3 db above the DI-2. The numbers i came up with are very close to what one would expect but only 1/6 of a s unit 1/2 vers 5/8 wave..... not worth worring about. |
Keithinatlanta
Intermediate Member
Username: Keithinatlanta
Post Number: 410
Registered: 3-2003
| | Posted on Saturday, October 16, 2004 - 8:28 am: |
|
Hey Bruce, I remember the ringo antenna from back in 70's. so will they wtill work for a CB radio base station?
Keith |
Highlander
Advanced Member
Username: Highlander
Post Number: 629
Registered: 12-2001
| | Posted on Saturday, October 16, 2004 - 9:40 am: |
|
Gonzo, the Maco V5/8 and V5000 are adjustable in length to cover either 10 or 11 meters, or just about anywhwere between 24 and 32 MHZ. It is a 5/8 wave whether it is on 10, 11 or anywhere else. If you are reading somewhere that it is "only" between 16 and 20 feet long, that source is incorrect. |
Bruce
Senior Member
Username: Bruce
Post Number: 1682
Registered: 9-2003
| | Posted on Saturday, October 16, 2004 - 10:06 am: |
|
Yes they do but if your going to spend that kind of money get a imax now if someone GIVES you one use it! |
Gonzo
Member
Username: Gonzo
Post Number: 56
Registered: 9-2004
| | Posted on Saturday, October 16, 2004 - 3:48 pm: |
|
Highlander the source I am looking at is the Copper Catalog itself!! It says 16-20 feet. 20 feet is not a 5/8 wave on 11 meters 22.6' feet is. It does make a difference.
"It is a 5/8 wave whether it is on 10, 11 or anywhere else"........Thats NOT possible, it can only be 5/8 wave on one frequency.
Bruce...geez I didn't say there was anything wrong with a "ringo" antenna. I simply stated it was a 1/2 wave antenna not a 5/8 wave antenna. |
Highlander
Advanced Member
Username: Highlander
Post Number: 630
Registered: 12-2001
| | Posted on Sunday, October 17, 2004 - 7:43 am: |
|
Gonzo, what I'm trying to tell you is that the Copper Catalog, or any other literature that says that the maximum lengh for that antenna is 20 feet, is WRONG.
I understand perfectly well that most 5/8 wave antennas for CB would need to be longer than 20 feet. I am not disputing that premise. I am disputing the information that you are quoting. The Maco antennas are taller than 20 feet when set up for 11 meters.
|
Bruce
Senior Member
Username: Bruce
Post Number: 1688
Registered: 9-2003
| | Posted on Sunday, October 17, 2004 - 10:14 am: |
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This is my 2 meter base antenna
 |
Bruce
Senior Member
Username: Bruce
Post Number: 1688
Registered: 9-2003
| | Posted on Sunday, October 17, 2004 - 10:17 am: |
|
Gonzo
There are many good antennas lots of choices. |
Patzerozero
Intermediate Member
Username: Patzerozero
Post Number: 139
Registered: 7-2004
| | Posted on Sunday, October 17, 2004 - 9:16 pm: |
|
hmmmmm.
not gonna take my maco v5/8 down to measure it, BUT as read directly from the maco assembly instructions, for 27mhz the overall length of the antenna from the top where the plastic cap goes to the bottom below the hole for the mounting bracket is 240"-that's only 20 feet.
now, either 1 of 2 things has happened here. due to inflation since i bought my maco 15+ yrs ago, 5/8 wavelength of the 11meter band has increased from 20 to 22.5 feet over the years OR maco uses special aluminum that has a different velocity factor than regular aluminum and my signal radiates faster thru their aluminum.
or the 3rd possibility is that one of those darned jogunn advertisers is working for maco and figured out how to make 5/8 wavelength @ 11m more than 2' shorter then normal.
guess i might as well start believing those stories about audio gain, huh?
so, highlander, if you say "copper catalog or any other literature is wrong", and i do agree with you because i have assembly instructions sitting right here, i guess that would mean the maco v5/8 is actually not a true 5/8 wavelength????????????
i've been deceived all these years. where's my lawyer!!!!!!!!!!! |
Bruce
Senior Member
Username: Bruce
Post Number: 1693
Registered: 9-2003
| | Posted on Sunday, October 17, 2004 - 10:38 pm: |
|
DANG! never even thought of that!
"either 1 of 2 things has happened here. due to inflation since i bought my maco 15+ yrs ago, 5/8 wavelength of the 11meter band has increased from 20 to 22.5 feet over the years"
Now has it's audio gain gone up too! |
Road_warrior
Intermediate Member
Username: Road_warrior
Post Number: 126
Registered: 7-2004
| | Posted on Monday, October 18, 2004 - 11:51 am: |
|
Bruce, how much Audio gain does a Imax 2000
have compared to the Maco 5/8???? LOL...
I tried to measure it myself, but, my
audio gain meter quit working...LOL
JIM/road_warrior/Central Pa/CEF 375 |
Tech833
Moderator
Username: Tech833
Post Number: 874
Registered: 8-2002
| | Posted on Wednesday, October 20, 2004 - 1:33 am: |
|
The other 2.5 feet is in the tuning ring and the capacitance between the vertical radiator center and ground. |
Big_thunder
Junior Member
Username: Big_thunder
Post Number: 19
Registered: 9-2004
| | Posted on Wednesday, October 20, 2004 - 6:52 am: |
|
Now does the imax 2000 hold 5000 watts? |
Highlander
Advanced Member
Username: Highlander
Post Number: 635
Registered: 12-2001
| | Posted on Wednesday, October 20, 2004 - 7:46 am: |
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What would be the point of running 5000 watts into an omnidirectional CB antenna? |
Big_thunder
Junior Member
Username: Big_thunder
Post Number: 20
Registered: 9-2004
| | Posted on Wednesday, October 20, 2004 - 8:08 am: |
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Highlander you didn't answer my question.. |
Big_thunder
Junior Member
Username: Big_thunder
Post Number: 21
Registered: 9-2004
| | Posted on Wednesday, October 20, 2004 - 1:05 pm: |
|
Ok thanks I think I may have burned out my antron 99 I had for sometime I've never ran 5000 watts through it but I have had over 2000 through it. by talking to some of the guys they said I'm not putting out the signal like should bought new jumpers didn't solve the problem so I'm going to coppers friday morning to pick up about 175feet of rg 213 and a imax 2000 . I was talking to a long time tech he said maco v 5000 groundplane is the best no comparison to the antron 99 he didn't know much about imax 2000. |
Gonzo
Member
Username: Gonzo
Post Number: 69
Registered: 9-2004
| | Posted on Wednesday, October 20, 2004 - 1:16 pm: |
|
"The other 2.5 feet is in the tuning ring"
That doesn't make it 22.6 feet tall, the tuning ring doesn't contribute to the height of the antenna, it only is a matching network.
-------------------------------------
I never said it wasn't a good antenna. It probably works just fine. But its NOT a 5/8 wave antenna on 11 meters. You can't get around physics.
------------------------
Take 972 divide by 27 = 36 feet (wavelenght of aluminum antenna divided by frequency)
5/8 of a wavelenght = .625
Take 36 feet divide by .625 = 22 1/2 feet..............not 20 feet, not 20 feet plus 2.5 feet of tuning coil.........22 feet 6 inches. PERIOD.
----------------------------------------
Thank you very much, I'll be here all week, be sure to tip your waiters and waitresses. |
Tech808
Moderator
Username: Tech808
Post Number: 3882
Registered: 8-2002
| | Posted on Wednesday, October 20, 2004 - 4:09 pm: |
|
Gonzo,
Just curious here as to what your actual experience is with designing or testing antennas and what equipment do you use to completely test the performance and what equipment do you use to test & plot actual radiation patterns.
I am quite sure others would also be interested in your expertise in the field of antennas and field testing as well as controled testing to assure the exact same setup is used on each antenna you test.
I / we would also be interested to know what type of equipment you use to perform these actual tests as well as your experience.
No need for tips just curious.
Lon 
|
Gonzo
Member
Username: Gonzo
Post Number: 70
Registered: 9-2004
| | Posted on Thursday, October 21, 2004 - 11:42 am: |
|
"what your actual experience is with designing or testing antennas"
Well in the early 70's I worked for Lafayette Electronics here in Syosset NY, helping to design and test antennas such as the Lafayette Range Boost & Super Range Boost, these were 1/2 wave end fed antennas with about 3.75 - 4.00 db gain. BTW they were $19 & $29 at the time! While I was there I also worked on the Lafayette 'Range Master 1' which was a carbon copy of the Starduster antenna, again a 1/2 wave antenna claiming 5 db gain. In those days we used B&W "Little Dipper" grid dip meters and EICO RF generators. These were used to tune transmitters,trim antennas to proper lenght,determine "Q" values, determine capacitance and inductance. These in conjunction with Field Strenght meters, could give you a relative idea of how a antenna was performing.
---------------------------------------------
I personally have built, Yagi's, quad's, verticals, dipoles, inverted V's, beverage antennas, rhombic antennas, horn antennas, long wire antennas and just about everything else.
---------------------------------------------
Today I still live in NY, and also have a home in Vermont, which now serves as my antenna farm. This is a farm with over 150 acres cleared flat. I have constructed many antennas on this "antenna farm" and have plotted there effectiveness by using L.C. Engineering Digi-Field field strenght meters & mobile CB radios, by actually driving around the antenna in a circular pattern at marked points with my ATV and this equipment. I then plot this information on a graph at both closest and farthest radiation points. I also vary the output power of the Test Transmitter (Cobra 2000) and plot the recieved "S" strenght points accordingly. Of course as Bruce has said you must make sure all other factors such as SWR's and antenna heights for example are equal.
I have used Rohn telescoping mast to achieve varying the antenna heights to see the effect on radiation patterns, however my 50 ft masts are getting a bit old, and need to be replaced soon.
-------------------------------------------
I have some equipment here, which I will take pictures of in my next post for you, however I am in NY right now and most of my testing equipment is in Vermont. I also belong to the Springfield Telescope Makers Association in Vermont.If you have heard of "Stellafane" as an astronomy gathering at all, then you have seen parts of my Vermont property. "Stellafane" is a yearly event and host to 1000's of amateur astronomers from around the country. Many astronomers like myself are also quite interested in Ham/CB radio. I have had amateur radio enthusiast bring their antenna design's up to my "antenna farm" to test their own antennas, while attending "Stellafane" at the same time. The event is in early August..usually a week before the persied meteor shower. If any of you are into astronomy I urge you to come to Vermont next August and say hello.
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Gonzo
Member
Username: Gonzo
Post Number: 71
Registered: 9-2004
| | Posted on Thursday, October 21, 2004 - 11:48 am: |
|
OK, I almost forgot, to answer you design question, you may download for yourself, some of the design programs I have used to make home-brew antennas, at my business website back directory: www.hobby.com/antennas:
www.hobby.com/antennas/pdl.exe
www.hobby.com/antennas/vert.zip
www.hobby.com/antennas/yagi.exe
www.hobby.com/antennas/SA3000.zip
www.hobby.com/antennas/quagi.exe
www.hobby.com/antennas/load-dip.zip
www.hobby.com/antennas/coaxdpl.exe
That should get you started.
--------------------------------------
As for related Radio activites. I also own The radio controlled hobby store. As you can see I have been around radio's and hobby tinkering all of my life. If I had a question about something I tested it personally. |
Gonzo
Member
Username: Gonzo
Post Number: 72
Registered: 9-2004
| | Posted on Thursday, October 21, 2004 - 12:14 pm: |
|
Diamond Engineering makes a desktop antenna testing system for those who have an interest. BTW. |
Gonzo
Member
Username: Gonzo
Post Number: 70
Registered: 9-2004
| | Posted on Thursday, October 21, 2004 - 12:18 pm: |
|
antenna plots |
Gonzo
Member
Username: Gonzo
Post Number: 70
Registered: 9-2004
| | Posted on Thursday, October 21, 2004 - 12:19 pm: |
|
some NY stuff I use |
Gonzo
Member
Username: Gonzo
Post Number: 70
Registered: 9-2004
| | Posted on Thursday, October 21, 2004 - 12:21 pm: |
|
control room |
Gonzo
Member
Username: Gonzo
Post Number: 73
Registered: 9-2004
| | Posted on Thursday, October 21, 2004 - 1:00 pm: |
|
I can see that I am going to have to permit everyone access to my hobby.com back-door directories,which is now blocked by my firewall, instead of doing that, anyone who is interested in recieving an antenna design program, please email me...and I will send you one.
I did load 6 pictures, hopefully they have come out correctly, its a little hard when all pics must be under 50K |
Gonzo
Member
Username: Gonzo
Post Number: 74
Registered: 9-2004
| | Posted on Thursday, October 21, 2004 - 1:04 pm: |
|
 |
Gonzo
Member
Username: Gonzo
Post Number: 74
Registered: 9-2004
| | Posted on Thursday, October 21, 2004 - 1:05 pm: |
|
 |
Bruce
Senior Member
Username: Bruce
Post Number: 1702
Registered: 9-2003
| | Posted on Thursday, October 21, 2004 - 3:05 pm: |
|
Intresting I still have several GDO's and use a noise bridge to tune my HF antennas. Back in the early 60's i hung out at the Lafayette store it was in Jamaca in thoes days. When i worked for Sperry R&D ( microwave ) here in clearwater ( early 80's ) we used mostly 96 GHZ and i did have time to play around at 10 GHZ with concept antennas ... a 3 elm beam is VERY small. Computer programs have been around since the apolo program and now almost any maching will run them. Yep lots of room to play with even a simple dipole ..... lots of room.
antennas are in short are fun but there are laws that apply and only "X" amount of gain one can get from one ...... |
Gonzo
Member
Username: Gonzo
Post Number: 74
Registered: 9-2004
| | Posted on Thursday, October 21, 2004 - 3:50 pm: |
|
Yes, I agree Bruce...mikes and antennas are fun.
Hey did you ever get my message regarding an antenna project?
Hey Bruce ever use a Palomar Tuner Tuner?? |
Highlander
Advanced Member
Username: Highlander
Post Number: 636
Registered: 12-2001
| | Posted on Thursday, October 21, 2004 - 7:07 pm: |
|
I see you have an MB5RB Microphone--how do those stack up to the Turners? I am a base microphone fanatic, check my profile! |
Bruce
Senior Member
Username: Bruce
Post Number: 1703
Registered: 9-2003
| | Posted on Thursday, October 21, 2004 - 7:59 pm: |
|
yes i did i thought i replyed let me check ....
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Gonzo
Member
Username: Gonzo
Post Number: 75
Registered: 9-2004
| | Posted on Thursday, October 21, 2004 - 8:13 pm: |
|
The Aries mike is okay, but I prefer the Turners. I have a few base mikes myself. |
Racer X (Unregistered Guest)
Unregistered guest
| | Posted on Thursday, October 21, 2004 - 8:15 pm: |
|
Gonzo - I see you like Turner microphones and compression microphones in general - good man! I've always been impressed with Turner microphones and compression microphones in general for CB use. How do you like the Ranger AC-7000 U/D with it's 3 levels of compression and 4 band equalizer? |
Highlander
Advanced Member
Username: Highlander
Post Number: 637
Registered: 12-2001
| | Posted on Thursday, October 21, 2004 - 8:52 pm: |
|
Haha Bruce, we both use the same GMRS and MURS rigs! I have been having a blast with MURS.
Is that a RadioShack Mini-FRS radio to the left of your Grant? I bought a pair of those when they were on sale. |
Bruce
Senior Member
Username: Bruce
Post Number: 1703
Registered: 9-2003
| | Posted on Thursday, October 21, 2004 - 11:05 pm: |
|
That box to the right of the grant is a EARLY 70's audio filter im tring to get my SCAF-1 to work it should be down 90db at 4 khz! to the left of the grant is a radshack mini frs radio and a 2 meter and a 6 meter and a 10 meter handheld. On a wip you will see a case that is a triband yaseu 6-2-440 ht.
The GMRS is used as a receiver hooked to my 11 db gain vertical and the MURS is hooked to a ringo ranger tuned for 151. The ft-100 is used on 6 all modes the ft-840 is my hf radio i now have a DSP filter for it it feeds a 40-10 dipole.
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Gonzo
Member
Username: Gonzo
Post Number: 76
Registered: 9-2004
| | Posted on Friday, October 22, 2004 - 10:05 am: |
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Racer X (what a great SN/handle) Yeah I am partial to Turners, the Ranger works good, but not any better than the Turners. My best audio reports ("sounds choice") are always with the Turner mikes, even the +M3 mobile mike. |
Patzerozero
Intermediate Member
Username: Patzerozero
Post Number: 148
Registered: 7-2004
| | Posted on Friday, October 22, 2004 - 6:39 pm: |
|
geez gonzo. i shoulda checked the forum before before i answered your message!
just kidding! keep up the good work!
my reply still stands, i ain't hiding i'm just a shadetree experimenter here!!!!!!! |
Patzerozero
Intermediate Member
Username: Patzerozero
Post Number: 149
Registered: 7-2004
| | Posted on Friday, October 22, 2004 - 6:43 pm: |
|
oh i forgot, so anyway guys, getting back to the question is my maco v5/8 a 5/8 wave antenna or is it just another fraud released upon us unsuspecting consumers?
doesn't matter, we all know it is the BEST omni cb antenna out there........... |
Racer X (Unregistered Guest)
Unregistered guest
| | Posted on Friday, October 22, 2004 - 8:12 pm: |
|
Thanks! My sister is Speed Racer, so as her older brother it was a natural choice.
I couldn't tell if one of the black microphones in the box was a Lafayette Range Boost or a +3B - not that they're any different - I though as you worked for Lafayette you might have one of those hanging around too.
Nice control room! What do you do with all of that equipment? It looks like you're set up for a flight simulator or RPG except for the keyboards, mice and the two towers on the floor.
I sometimes run multiple monitors on my main system and I've got a few more systems that I use for specific tasks. I use a KVM switch so I can use a single keyboard, mouse and monitor with all of the systems. It helps me to keep things neat too. I have a tendency to fill up any horizontal surface with equipment or media, so freeing up space is an important factor for me. |
Gonzo
Member
Username: Gonzo
Post Number: 77
Registered: 9-2004
| | Posted on Friday, October 22, 2004 - 8:58 pm: |
|
Yes it was a Lafayette Range Boost. Same as Turner's, was made by Turner.
I use a KVM switch on my firewall,web server,dns server,mailserver equipment, thats in another location. I have the same tendency's as you as you can see.Yeah, I'm a bit messy. |
Mikefromms
Intermediate Member
Username: Mikefromms
Post Number: 255
Registered: 6-2003
| | Posted on Tuesday, October 26, 2004 - 2:14 pm: |
|
I'm convinced that close to the ground nothing will out hear and out talk the Astroplane. At under 30 ft to the tip of antenna I'd choose the AP, if over 30ft at the tip I'd choose the Imax. That's my current thinking on this comparision.
(ideas subject to change based on time of day and day of week) LOL!
mikefromms |
Tech833
Member
Username: Tech833
Post Number: 55
Registered: 12-2001
| | Posted on Friday, October 29, 2004 - 2:43 pm: |
|
"That doesn't make it 22.6 feet tall, the tuning ring doesn't contribute to the height of the antenna, it only is a matching network."
Gonzo,
Everything from the shunt onward to the tip of the radiator counts toward total electrical length. Everything from the shunt downwards does not count. The vertical portion of the radiator counts toward the gain. The horizontal or matching portions count against it. Since the tuning network is so small, the negative effect is minimal. With your qualifications, I should not have to tell you this. |
Gonzo
Member
Username: Gonzo
Post Number: 83
Registered: 9-2004
| | Posted on Saturday, October 30, 2004 - 4:31 pm: |
|
Yes you are right. So by your own logic you are Now in agreement with me. |
Airplane1
Intermediate Member
Username: Airplane1
Post Number: 214
Registered: 5-2004
| | Posted on Tuesday, November 02, 2004 - 12:52 pm: |
|
All I know is my maco v is only 7ft to base of antenna and I regularly talk 25-40 miles at night and talk lots of DX even to CA. and to France from PA and there are lots of mountains around me and I live in a small vally.
so i`m very happy with it. I would recommend it to any one looking for an antenna.
People cant beleive me when I tell them my antennas 7ft off ground, Thats good enough for me.
I wish I had an Imax 2000 to put there to test and see if it was as good.
Oh, and it was very easy to tune and i`m a novice and the maco v is the first base antenna I put together. SWRs are flat at almost perfect at a bit over 1.0.
Just my 2cents. |
Mikefromms
Intermediate Member
Username: Mikefromms
Post Number: 265
Registered: 6-2003
| | Posted on Wednesday, November 03, 2004 - 11:15 am: |
|
Glad you Maco V is working good for you. Without a groundplane kit at that height the ground interference would disrupt the performance of the Imax 2000. The Maco would like outperform the Imax a little bit at any height, but for simplicity, performance and especially broadbandedness the Imax is the total package. You have a good antenna and some people would be amazed that you were able to get it tuned so well.
mikefromms |
Tech833
Moderator
Username: Tech833
Post Number: 880
Registered: 8-2002
| | Posted on Wednesday, November 03, 2004 - 4:28 pm: |
|
Gonzo,
It is not about agreement or disagreement with you. All I care about is that my fellow forum members get the most accurate information possible. I do not care if anyone agrees with me or not, only that my information is accurate. |
Marconi
Intermediate Member
Username: Marconi
Post Number: 482
Registered: 11-2001
| | Posted on Thursday, November 10, 2005 - 1:45 pm: |
|
Today I did a search on Coopers and found this interesting thread that I had missed from the past.
Based on what I see of Gonzo's depth of experience, I am a bit surprise at Gonzo’s responses about the Astro Plane not being a 5/8 wave. To base this simply on the fact that it is shorter than 22.5’ feet in overall length is flawed. The tipper for me was his erroneous contention that Avanti, the developer of the Astrop-Plane, did not advertise it as a 5/8 wave. It is true that there were older ads for the AP that did not indicate this characteristic in the antenna, but that omission does not change the facts. If you look in the extensive owner’s manuals that Avanti shipped with each antenna they sold, you will find this fact is on page 5 of the manual. Right at the very top if states “Co-inductive 5/8 wave Omni directional CB base antenna. When it changed to Top-One had nothing to do with this 5/8 wave issue.
Fact is that none of these longer verticals are at a resonant length. Whatever the length beyond a resonant ˝ wavelength that a longer radiator will work out to be depends on the type of matching device used. This alone determines the nature of the antenna and how it is able to bring the non-resonant radiator into resonance. This whole issue must be view from an electrical perspective.
Frankly I believe the use of the term 5/8 is the cause of the confusion in this issue, but I don’t have a better term handy. I believe all these verticals that are longer than a 1/2 wavelength, are very similar in the way they act to lower the radiated pattern to the horizon and increase gain. The only difference is the way they are matched and the varying lengths that develop as a result. It isn't a math thing even thought I have no problem with using the terms that are often used.
To me they are all good antennas, but I still think I can work a 1/4 wave radiator with a good ground plane and something to decouple the feed line, and still make just as many contact as you boys with them longer vertical antennas.
Just my belated opinion,
Marconi
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Road_warrior
Advanced Member
Username: Road_warrior
Post Number: 908
Registered: 7-2004
| | Posted on Thursday, November 10, 2005 - 5:46 pm: |
|
First of all S-units in a radio are not
totally accurate. Spacing antennas 50 ft
apart is not an accurate test. Since i've
tested these two antennas myself i will
agree the Imax 2000 is stronger on transmit
and recieve than the Top One.
But, the problem i had here was the excessive
high noise level of the Imax, so, even though
it was stronger, i could hear weaker signals
alot better here on the Top One.
That's why anymore i have a hard time recommending
any one antenna to anyone due to the fact that
they sometimes react different in other areas
and to different surroundings. Because i have
found out that what doesn't work for me, has
worked well for others. |
Kid_vicious
Advanced Member
Username: Kid_vicious
Post Number: 815
Registered: 9-2004
| | Posted on Thursday, November 10, 2005 - 10:51 pm: |
|
hey marconi, nice to see you back on the board!
you were missed.
i am still running the same Top One antenna that a bunch of us were discussing months and months back.
i can tell you guys this much; when the caonditions are a'rollin'; i can get back to pretty much anyone i hear.
as a matter of fact, today wasnt that great compared to the way its been earlier in the week, and still, on ch. 6, with my little kl300p keying at 25watts; i was able to make a solid contact with 187 in new jersey. (i live in las vegas)
i know the reason that contact was possible was because of my antenna.
i love it. one thing that i like that i ithink others may overlook is the fact that this antenna needs no tuning and no matching network.
it is resonant by design, and i like that.
just opinions here folks,
matt |
Marconi
Intermediate Member
Username: Marconi
Post Number: 483
Registered: 11-2001
| | Posted on Friday, November 11, 2005 - 6:39 am: |
|
RW, your are correct that precise testing conditions are important to good results. One location is best, but in the time it takes to switch the antennas out, things can happen to conditions. There is something to be said when comparing, about being able to switch between antennas with a simple flip of a switch and checking the responses. Of course we have to consider that we have antennas at two different locations using two different systems. That could be resolved to some degree by making good reports and then switching the antennas between locations and doing the comparisons again.
When using the same support to install the antennas, conditions may not change while making the change, but I wouldn't count on it. Did you consider this in your test, considering the test had to be done some time apart from each other?
Also the AP was designed with the idea that the tip height of the antenna was the controlling factor in its advantage. If you tested the Imax and the AP at the same height to the feed point, which is usually at the tip of the support used, then the Imax has a considerable advantage in height. If the tips of the antennas were equal in height, then maybe the tests would produce a more similar result between the two. That was my point about comparing the AP to others. I also contend that the AP got a bad rap about only working well if it was close to the earth.
Thanks Kid. Your contention is another point I make all the time. Even though one antenna may make a point or two better signal on the meter, I cannot recall ever losing or failing to make a contact with even a 1/4 wave ground plane antenna when comparing it to a 1/2 wave or longer vertical.
Without knowing the condition of my line during one period of time in my radio experience, I had a Starduster up and was only getting .25 watts to the antenna. That's right less than one watt out to the antenna. The coax was contaminated by rain water. I always just talked to local buds like most of us do. When skip would roll in, I would continue to talk right along with the rest of em'. Most were runing 12 watts and more, I'm sure. Other than my giving everyone a lower signal or maybe in some cases no signal at all, everyone was still able to hear me or I would have surely suspected something was wrong long before I did. And, believe it or not, during all that time I had great ears. I though it was the antenna, but maybe it was because I had the fouled line and I didn't have the noise others complained about due to the attenuation of the line.
Just goes to show me how little we really need to comunicate. Sometimes I wish I had not thrown that line away.
Marconi |
Road_warrior
Advanced Member
Username: Road_warrior
Post Number: 909
Registered: 7-2004
| | Posted on Friday, November 11, 2005 - 7:58 am: |
|
Yeah, I test them one right after another. And
yes things change. But, i also like to run each
antenna sometimes for months to get the feel
of it. I'm done doing this stuff as i am
disabled and my body parts are not moving like
they once did. So, i'll sit back and read about
other people doing it now....LOL
But, mostly i ran an antenna for months, to see how it does on static, recieving, transmitting, TVI-RFI problems ect. I'm very close with all my neighbors, so, i sometimes had my wife talk on radio while i listened at my neighbors for interference problems to there equipment and then tried different things to cure it on my end. Been some hair-pulling times...LOL...I had No interference problems with the Top One what-so-ever. Had just alittle with the MacoV5/8, but,
nothing major and was easily curable. Imax,A-99
ect. kicked my butt! Never could bring heavy
static or RFI problems under control with them.
|
Kid_vicious
Advanced Member
Username: Kid_vicious
Post Number: 827
Registered: 9-2004
| | Posted on Saturday, November 12, 2005 - 10:22 pm: |
|
marconi, you know what would have happened; you wouldve saved that coax, and then late one night, in desperation; you would forget and use it to make a quick jumper, and spend the rest of the week troubleshooting your new antenna.
raod warrior, what antenna are you currently running and are you happy with it?
have a fine one,
matt |
Dalowe
New member
Username: Dalowe
Post Number: 1
Registered: 3-2007
| | Posted on Saturday, March 17, 2007 - 1:20 pm: |
|
I'd like to repeat emphatically what Marconi said, which was that this test sounds like it was done referencing the height of the antennas from the bottom. You can't do that with an Astroplane, you have to reference from the top tip of the antenna. If you do that, I wouldn't doubt that the performance would be much closer. I contend that the Astroplane will out-hear the IMAX at that altitude because it is a quieter antenna. In my opinion, hearing is everything.
One thing you will notice is that this is easier said than done, which is the reason for the Astroplane’s mediocre reputation. Putting that much unsupported mast up inside of the Astroplane is not for the light hearted. I used to use nylon rope in place of metallic guy wires. I never had one of those ropes break, even under high winds. |
