Gizmotchy Antenna Review

[TonyV225]

Hamer you will be amazed at that antenna I am with mine. People say that cant possibly work like that but guess what is most certainly does work and very well to. I have people look up at mine and say that its is impossible for that antenna to work in a 3 element per hub configuration and I say well you hear me and I hear you and people you sometimes dont hear I hear so ITS OBVIOUSLY WORKING!!!

I guess its just one of the radio wonders to some. Like I said I love mine and will add a booster kit maybe this fall or next spring. Im not in a hurry because mine works fine at 3 elements

 

[Moleculo]

The spacing and size of the two director elements seems a bit odd to me because I wouldn't expect them to be identical. The 2 meter version I put up ended up having a shorter second director which was also spaced farther than the first director. If you use the spacing indicated on my version for 2 meters, it should be fairly straight forward to figure out the correct spacing for 10/11 meters. Check out this pic to see the difference between the spacing on my 2 meter antenna vs. your 11/10 meter version:

 

[TonyV225]

I dont have the extra booster element kit so I am no help here unfortunately

 

[Marconi]

Here is my question before it goes in the air.

The picture assembly say the elements should be as follows.

REFLECTOR = 109 INCHES

SPACING FROM REFLECTOR TO DRIVEN = 3 FOOT 8 INCHES

DRIVER = 105 INCHES

SPACING FROM DRIVER TO FIRST DIRECTOR = 5 FOOT 2 INCHES

DIRECTOR 1 = 100 INCHES

SPACING FROM FIRST DIRECTOR TO THE SECOND DIRECTOR = 3 FOOT 8 INCHES

DIRECTOR 2 = 100 INCHES

All elements attach to the hubs are 1/2 O.D. diameter and reduce to a smaller 3/8 O.D. of the element.

The Boom is 12 foot long

Does this seem correct?

Can someone double check this on Eznec?

It just seems the front director should be a tad shorter than the first???

I am just basing this off assembling a Moonraker and a Shooting Star.

Help me out before I put this in the air

Hammer, beams are hard to figure sometimes.

The basic trends in beam construction and the spacing between the Dr/D1 is usualy the narrowest space along the boom of a 4 element. In your case it is the widest, and I sure don't get that.

I think taking Moleculo's advise to question the numbers you see is a valid question, and I based that on my thoughts above. Another thing is when you add up the spaces you give us, it makes the boom longer than the length of 12' you show. It's not much, but why is that?

This Giz has a very short boom for a 4 element, and the generally the length of the boom is what determines gain performance, more-so than the number of elements. That said, and including the apparent issues with spacing you raise, I hear it said all the time---how well these Gizmotchy antennas work. So, this Giz seems like a contradiction to me. I could be wrong however, so I won't argue what these guys say, but I really wonder how they know.

Will any of this make a difference in the way beams work? I can't prove anything, but I see differences in performance with my beams, working as they should to working almost like an omni-directional. But, I can't argue with all the folks that claim the Giz works great.

The wide spacing you show between Dr/D1 will certainly help to make the match look better and is easier to achieve. It may also allow a wider bandwidth, but IMO this will all come with a heavy cost to gain and rejection, 62" is very wide for such a short boom. The Moonrakers and Shooting Star's are generally 44" - 54" not 62" like you indicate.

Again, take Moleculo's advise and re-consider the measurements.

 

[Marconi]

Happy here is an element spacing chart from "The ARRL Antenna Book" that gives workable ranges for element spacing for various beams from 2 - 8+ elements assuming the boom length is porpotional to the spacing provided.

 

[Happy_Hamer]

Well it has been a few weeks but I am following up with the review thus far.

The antenna was put up on a 20 foot temporary mast.

I hooked up my 2970DX and made several contacts only at 20 foot high.

Unfortunately I had some problems.

This is the reason it did not go on the tower.

The hose clamps provided were inferior and would not allow me to tighten enough to hold the elements to the stubs on the boom. The clamps would strip out and become useless.

Sure I could drill the elements to the solid stubs, this is recommended in the directions for a permanent installation. I did not want to drill it because I knew I would be adjusting the antenna for 10 meter after the CB band test.

Well while it was on the 20 foot mast a small gust of wind shook the antenna and down came 2 elements. This was not a note worthy gust of wind either. So the mast was lowered, and the elements were re-installed. Tried to re-tighten all the clamps and they were at the max. I stripped 4 more clamps. This was getting old. I bought a few replacement hose clamps, this time I used stainless, from the auto parts store and they were a little stronger. As I was tightening the replacement clamps, the antenna shaking caused even more elements to fall off. :bdh:

I installed all new clamps on the boom (12) and it is still not perfect. I will end up drilling it and using set screws.

I am looking for small enough clamps that I can tighten down similar to the supra style clamps

​

More to come when I buy more hardware to keep it together.

 

[loosecannon]

good info there hamer!

with the bottom elements sloping toward the ground, they definitely need to be secure!

sounds to me like whoever gizmotchy is having do their machine work for them is not doing a very good job, or was given bad specs.

to me, it looks like the slots in the elements are not deep enough, and also the gap in the slot might be too narrow.

when you tighten a hose clamp all the way down, do you notice the sides of the slots touching each other?
like the gap should be wider?


the only other thing i can think of would be since the elements are two piece assemblies, might you be putting the wrong end of the larger element piece towards the boom?

LC

 

[Marconi]

HH, like LC suggests, in this kit larger of the two tubes for each element should be slotted on both ends, right? I can't tell from the pictures.

LC is also right about the depth and width of the slots as well. If you can, also check and see if the studs were machined with a slight taper toward the tips. They should be perfectly straight without any taper. Such a taper at this point could cause the elements to wiggle excessively with the wind and come loose.

Did the clamps in your image come with the kit? They don't look the same in previous pictures you posted. If they're not all Stainless, then they're not worth a hoot on and exposed antenna anyway.

All such little things might be explained by a new owner producing the Giz. So far with Moleculo's 2 meter and your 11 meter, it looks like the Gizmotchie is a looser and I've never heard that before.

 

[Robb]

Well, this antenna isn't built like a plastic car model made by Revell. Tom Charles (owner of Gizmotchy/Maco antennas) told me that some time and attention to the instructions would make it right. The problem I have with that, is that the instruction sheet was sooo ridiculously small and hard to read. So I scanned the instruction sheet as sent with the antenna and enlarged it "a bunch" - just so that it could be read.

Having said that, the actual fit of some of the parts - I felt- was just a little too loose. The fit between the three boom sections was fine; but it might sag if not secured with more than a couple of screws. Gizmotchy has an additional boom support kit if you intend to buy and use more than a four element beam. The 4 element beam kit is the edge of that limit for the need of additional support.

I used to be a machinist years ago, and I surely would have machined those radial flange studs a little wider for a better fit - to the same inside diameter as the radials. As they are, they are a bit too loose IMO. Making those radial mounting studs a proper fit for the radials would have made the hose clamps work fine, as the radials would be tighter on the studs before the clamp was in place. I would have also pre-drilled the radials themselves near their base so that the stainless steel sheet metal screws would have been a cinch to install. When looking at one of these antennas assembled; one would think that it is a no-brainer. But when one considers that ALL of the dimensions are critical; one needs to re-evaluate their first assessment...

The boom -I felt- should also have been pre-drilled on a jig - so that the alignment of these radial flange studs and their locations would be in perfect positions. This is pivotal point of the assembly; as these dimensional points are critical to the overall tune of the antenna.

The positives to the antenna was its light-weight construction for its assembled size. The dimensions and the machine work were very well done otherwise. But I would make the instruction sheet much larger - and at least make it a couple of pages long in order to give sub-assemblies greater detail that they deserve. Not a simple assembly - even with the instructions provided - because the dimensions/layout were not definitive enough for a non-machinist to understand. The print of the instructions was also a little bit blurred.

Basically, it still is not a bad antenna - and has room for some improvements. It could -and should- be revised. I would put the kit together so that anyone that buys it can assemble it in a 1-2-3 step procedure; and go as far as marking the parts and ensuring that assembly could be done by a 12 year old. That would ensure more sales and a more consistent finished product! As it is now, I would not recommend for the newbie; unless you do as I did and enlarge the instructions first. And bring a LOT of patience and some real machining skills.

I did not set the antenna up and test it. I did sub-assemble some parts to get an idea of the fit and finish of the machine work. I sent it to Hamer so that he could evaluate that portion and give his review from another perspective.

Picture:
I'm not surprised that Hamer had some of the difficulties that he did. Nor would I blame him either. As one can see from Hamer's photo below, that aluminum stud sticking out is one of the problems created by the designer. That is a mount for one of the radials. They were machined too narrow to get a proper fit and hold the radial; maybe another .05" wider would have made it correct.

In addition, Hamer's problem with finding the proper locations for these radial stud flanges along the boom section could have been solved at the mfr's end. It could have been solved if Gizmotchy would have pre-drilled and located these points along the boom itself - and/or made the instruction clearer and easier to understand.

You can also see the thumb screw head between the radial stud and the radial - on the flange itself. Certainly, I would have designed this section differently as well. I would have used a regular bolt with a tapered end to locate it along that boom. Provided -of course- that there would be a corresponding pre-drilled hole along that boom. That would solve both the location problem and not allow the radial stud flange from quite possibly getting loose.

 

[TonyV225]

I have had no problems with mine coming loose although I drilled mine and set them as the instructions stated to. I did however strip one of the useless hose clamps as you did so I bought a stainless replacement and again it was drilled and set screws that were provided were installed so the hose clamps wont be a problem anyways.

Ive seen elements on all these CB type beam antennas come loose so set screws were always a plus as far as making things a bit more worry and most of all TROUBLE free

 

[radioreddz]

has anybody that uses the Gizmotchy style or Jogunn style star series antenna beam with the slanted radials had the standard yagi cross style shooting star or moonrakers to compair performance with. i know a guy running the gizmotchy 4 element and another guy using a Maco Shooting Star and is seems like the Cross style shooting star does better dxing & ground waving. i live 24 air miles from the guy with the Gizmotchy and when he switches between his Gizmotchy and his Maco V5000 it does not seem to have much difference in his signal very very slight notice in signal strenght but a little more audio. maybe his aren't put togeather right.

 

[Hc714]

Any thing new yet?

 

[Hc714]

So, is this review going to take place or are we to believe that the antenna is such a piece of crap that its not worth putting together to review? Any way hope thats the reason and things are ok with the Hammer.

 

[TonyV225]

I cant believe your having that much trouble with that!!! LMAO!! Mines been up 2 years and I had to replace one element due to a goose hitting it but the goose laid on the other side of the driveway so he wont do that again.

As far as hardware I replaced one of the small clamps that tighten the element I stripped it out on that last torque type thing I put all the set screws in that came with the beam not a single problem!! It works excellent anyone want to here how they work just shoot me a PM and set up a talk time and frequency.

Ive talked to other people running these and they to have had good luck and like the antenna I did a lot of research and made tons of phone calls to distributors on all the beams like this before I went with the Gizmotchy. I read the other reviews ETC. I actually have mine up over several other choices of beams I have and had at the time packed away in my outside building. I am going to however get another one of my towers put up and will put my shooting star dual polarity 4 element up and a big new Joe gunn up I have to go pick up yet. I am really curious what the difference really is between these other bigger antennas and this little Gizmotchy. Ive ran mine on 10 meters as well with a tuner of course.

Im actually thinking about selling all these damn Superscanners I have and adding the booster kit to my Gizmotchy and Im wanting another one of these Gizmotchys. Bill you get fed up with that antenna send it my way just let me know what the shipping is ide like to try the booster kit against what it does with the 3 elements if need be Ill just pay Tom for the thing Im gonna have to razz him anyways for sending you and Robb a gem and headache product LMAO!!

All in all it sucks and is to bad your have a hell of a time getting that thing going but thats my luck as well on some things. Everyone else has one that works and mine didnt LOL!! I went through this with a Galaxy and Mirage 88 99 and a Galaxy 2547.

 

[Moleculo]

I talked to Hamer last night and he said that work has him traveling all over 1/2 the country right now. So, it will probably be a bit before he gets back to this. The last time I talked to him about this antenna, he said he was pretty frustrated with all of the installation issues, especially since it kept falling apart every time it got windy.