Signal Engineering antennas

[akzo1990]

A few months ago I bought a new Signal Engineering Lightning 4+ on Ebay. After looking at how the antenna is built I am a little concerned about the plexiglass mounts for the tuning stubs. My concern is how much UV protection do they have, considering that they will be exposed to the sun. I plan on putting this antenna up this summer at 108 ft. and I would like to leave there for awhile. Does anyone use this type of antenna and if so how is it holding up?



73,

ED

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[hossless]

Marconi is a great guy, he will go out of his way to help you with your beam antenna. He gave me alot of helpful information when I got my first beam antenna and didn't know the difference between a director element and driven element.



Hossless


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[Phil501]

I too agree with Hossless, in the past Eddie has helped me out with my SE SuperHawk Quad.......He is a great forum member and knows what he's talking about........Good luck with the 4+.........I'm sure you'll enjoy it........

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[Jay in the Mojave]

Hello Dawginfi:



I have to somewhat agree with you there.



I helped a local put up a SE 4 element Quad Beam Antenna. I have to go back home and get better clamps, and some Dilrin for the tuning wire mounts. And this was a new out of the box antenna!?!?!?!?!?



We asembled the antenna per the assembly instructions, and set the tuning adjustements as shown in the assembly manual. Other s went over checking the antennas lengths and such, as a second set of eyes type of inspection.



The performance was not as expected. As a I-10K 5/8 Antenna was much stronger than the SE 4 element quad. And I suscept the tuning methode to be way wrong.



Did we assembly the antenna the wrong way, or is there something we didn't know about, or anybody have anything they say about the SE 4 element quad antennas?????????????????



Has any body called the guys at Signal Engineering and asked for help, and got some sort of help? Maybe I will to see what I can see.



Jay in the Mojave <img src=http://www.wwdx.org/smilies/posticon44.gif ALT=":44">


</p>Edited by: <A HREF=http://p067.ezboard.com/bworldwidecbradioclub.showUserPublicProfile?gid=jayinthemojave>Jay in the Mojave</A> at: 1/23/05 7:16 am

 

[Jay in the Mojave]

Hello Marconi:



Marconi Said:

"Jay, you have seen this antenna first hand, right? Would you agree that this tuner, the hot side only for now, is about a 1/4 wave long and that it hooks directly to the loop at one of the corners, a fiberglass support, and that this wire loop is ruffly a full wavelength long without an insulator, and that it is a continuous loop? I'm not talking about the shrink wrap insulating material that is located at each support corner either.



When you helped build the one you mentioned, did you use and analyzer? Was it responsive with adjustments to the tuner or was it like Dawginfi said, "...It wouldn't tune with a MfJ analyzer."

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The SE 4 Element Quad Beam Antenna was feed the same way the Avanti PDLII 2 Element Quad Antenna was feed, as far as the connection to the quad loop wire, is concerned. (The PDLII used Gamma Matchs, which can only match to a lower than the coax impedance) The SE Quad Antenna used what looked like a 1/4 wavelength type of pickup matching circuit.



The SE 4 element quad had two points on the driven element loop that where feed, again just like the PDLII Quad Beam Antenna. That is the feeding wires where attached at the bottom and one to the side of the driven quad element. Then these feeding or connection wires where brought down to the Boom, and mounted on a Plastic Insulator, and routed towards the forward end of the beam towards the first director. These two wires are routed thru another Plastic Stand-off and bent back toward the driven element, and connected to a Brass type rod.



The center wire of each coax is connected to the separate brass type rod, and the shield of the coaxes is connected by a clamp to the Boom.



Maybe I need to post a simplified drawing for you.



Yes I used a MFJ259B Antenna Analyzer, and another analyzer, and they both measured the same SWR. We had to adjust the connection point on the brass type rod to lower the SWR, but didn't see a lower SWR as the instructions had shown.



Thas why I wanted to know if we where doing something wrong and would love to hear how to adjust the SE 4 element beam. Again thats why I wanted to call the guys at SE for help.



Would like to hear from anyone if they have a fix or suggestion.



Jay in the Mojave



www.a1antennas.com <img src=http://www.wwdx.org/smilies/posticon44.gif ALT=":44">


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[Jay in the Mojave]

Hello Marconi:



I am going by my memory here, I will pull the assembly instructions from my files and see. As I am not really certain that we are singing from the the same song sheet here.



But I am sure the connection to quad driven loop is the same. I don't remember a insulator in the PDL-II quad antenna.



I'llllllllllll be baaaaaaaaaaccck.



Jay in the Mojave



<img src=http://www.wwdx.org/smilies/posticon44.gif ALT=":44">


</p>Edited by: <A HREF=http://p067.ezboard.com/bworldwidecbradioclub.showUserPublicProfile?gid=jayinthemojave>Jay in the Mojave</A> at: 1/31/05 5:21 am

 

[lil-bump]

Sinal Engineering L4+

Hello guys, Hello also to you Eddie, we haven't talked in a while

I thought I would shed some light on to SE feed system. rather try to explain the theory here is the patent#4,236,160 for the feed sytem. In a nut shell this antenna is voltage fed and NOT current fed like a traditional quad. That what allows this antenna to be dual polarity. Also I can't believe a 5/8 ground plain can perform better than the SE L4+ quad. Something has to wrong. I've running one for about 2+ years and the performance of this antenna is unbelieveable

 

[CDX1220]

hello forum .i have ran a SE L4 for years ,i have never had any problems,i have ran the super hawk 2ele,quad and it to worked really well .imho SE quads cant be beat in performance, i to find it hard that a 5/8 wave can outperform 4 ele quad.i have ran the m106 and se quad out performed the m106 hands down.but in all of my opinion i could be wrong .

 

[Jay in the Mojave]

Hello CDX 1220:

I also think that a 4 element quad should do better than a 5/8 wavelength ground plane. Thats why I was asking if anyone had a suggestion or could help. Because it wasn't working right, if a 5/8 ground plane did have better performance.

Jay in the Mojave

 

[lil-bump]

signal engineering

10 years ago when I first tried this antenna I made a crucial mistake;I put the elements on backwards Where the reflector was supposed to be I put the last director and then I laid all the rest of the directors in that order. Trust the antenna will not talk at ALL. also what I found out At my installation I position my antenna like the direction say my verticle feed point is resonant around 26.5 MHZ. but when I rotate the beam and have horz at 3:00 and the verticle at 12:00 both of my feedpoints are resonant around channel 20. I believe the verticle feed point does not being so close to the tower neck.
One other thing this antenna is tuned for the middle of the CB band this is where it should be matched at. Moving the coax along the tuning stub will NOT and does NOT change the resonant point.

 

[lil-bump]

se antenna

hey CDX 1220,
Have you ever had a problem with your elements stretching Mine have not because I streched the heck out them before I installed the antenna. I was just wondering does Signal engineering pre-stretch their wire enough.

 

[CDX1220]

hello lil- bump .no i have had no problems at all .i strectched mine too.

 

[lil-bump]

SE quad

Which antenna do have? The white lighting or the lighting 4+. I have the Lighting 4+. And this antennna is close or even better than my M-106. Also did you have a match problem on your verticle side? I have my feed points at the 12:00 and 3:00 position when I run the verticle feed point at 6:00 I have a problem with match on the verticle side.
I just replaced my elements. I had a nasty storm in april with extremely heavy snow my spreaders bowed so much that my drive element and reflectoer broke so I replaced all of my elements. I removed the 18" aluminum supports that support the fiberglass spreaders with 72" to try give my spreaders a little more strengh. I did not re-stretched my elements this time hopefully Signal Engineering stretched them enough.

 

[nomadradio]

I have a "clone" of the Lightning 4, made by a local guy. He optimized it for tight rear-corner rejection, rather than for forward gain or front-to-back.

Think of the full-wave driven-element wire as two end-fed half wave wires in parallel. They just happen to join at their far ends.

The patent abstract sorta explains how the folded quarter-wavelength feed wire matches the 50-ohm coax up to the 400 ohm (or higher?) impedance of the driven element. That's what they mean by "voltage feed" in the patent.

The spacing of the feed wire above the boom is critical.

So is the choice of plastic used to support the "spaggetti match" (what the locals call it). I have a scorched, melted piece of the WRONG type clear plex that a customer gave me. Tried to build one of these, and then fed it WAY too much power. His kids came running inside when he fired up the 8x3-500Z box, to tell him that flaming fire bombs were dropping from his antenna. Set the plex on fire, and melted globs would drip off, flaming to the ground.

Now he tries a sample of plastic in the microwave before using it to support a spaggetti match. If it gets hot in the microwave oven, it's the wrong kind of plastic to use on an antenna.

Oh, and Lil-Bump, thanks for posting the SE patent number. Been promising myself I'd call SE and ask them the number for some time. Just never got around to it. Isn't mentioned on their web site.


73

 

[lil-bump]

se quad

Thanks for the info on the plastic insulator I just made 4 of these out of plexiglass. I don't run any power any more I only run a EF johnson ranger about 50 watts. You are correct the distance of the speggetti match is critical. It can't be too close or to far away from the boom. I modified my spreaders I remove the 18" alluminum spreaders and replaced them with 72" piece I'm hoping this will give my spreaders a little more strength during wet heavy snows. By doing this I had to install the plastic separators on my spreaders because I add 50% more alluminum and I had to keep the spaggetti wire the correct distance away from the extended alluminum spreader. I also installed an earth ground of #2 flexible cable and attatched it to boom to mast plate to make sure the spaggetti wire has a good ground to work against. But My lighting 4+ works extremely good. the only thing I was going to try was run my feed system the way its shown in the patent where the spaggetti wire is ran next to a grounded wire this would keep the spaggetti wire from transmitting because its entire length would be working against a ground. the way SE sells the beam now is the wire is only working against the ground when its running along the boom once it hit the fiberglass spreader it's no longer working against a ground I think this would help with rejection from unwanted areas. but I believe I would have modify the length of the spagetti wire or flexible feed line Thats what I call it.