Maco V-Quad....

[Oatmeal]

Any you guys running one of these ?....

If so, how does it perform.....and any pros and cons ...

 

[hotrod]

ive seen one about 40 miles from my qth a few years ago dont know who had it.
but i recently went by that place and the wire was twisted all around it.
from what ive heard on the radio there GREAT dx antennas as there almost flat
but there not the greatest local beam.lately on 38lsb ive talked to a few guys
that use whats called a jogunn skip jack i think. its the same as the v quad
only its ALL alummin. where the v quad uses wires that has to be exact lenth.
i think jogunn version would be much more durable

 

[Mudfoot]

I ran one in the early 90's. I really liked it. Side rejection was good. Turned it with a cheapo TV rotor. I would use another in a heartbeat, great antenna. Another local had (still has) a stacked pair. Haven't heard him for years, I think he passed, but his quads are still up.

Can't beat a quad, no matter it's configuration.

If we had todays durable spreader arms and the like, I believe yagi's would be everyone's second choice antenna. Early quads were constructed with flimsy shit that didn't hold up, but the yagi did.

A quad would always be my first choice.

 

[Marconi]

Oatmeal, here are my Eznec models for a dipole vs the dipole with the elements slanted down at 45* degrees in a V-Quad configuration. I did not tune the the first V-Quad model marked "Not Tuned," and I tuned the last model so you can do a little comparison of a horizontal dipole vs. the V-Quad tuned and not tuned well.

Note: The first dipole was made using only 1 wire. Eznec will not allow any wire to be bent, so I made the 2nd dipole using two 1/4 wave wires, and I fed it in the middle like the 1st model. Notice there is a little difference, but not that would matter at all. In theory it tells us there is a difference, but in real life the difference doesn't matter, just another case of what I seem to claim all the time.

I slant the elements on the 2nd dipole model down to 45* degrees, but I left the dimensions exactly the same, and doing this slanting changes the match at the feed point. Notice this match change in the Source Data report, and there you will see that this slant does make the natural match better, but it is still not perfect, it shows some reactance.

So, I tuned its mismatch out to a near perfect match for the last model noted as "Tuned." This we can see makes for a very good SWR, but this hardly makes a difference in the gain or the angle. Slanting the radials, in this case, does raise the maximum angel a little bit, because the V-Quad is set a bit lower to the ground as a result of slanting.

All the antennas shown here are at 36' feet to the feed point.

I just posted the results in a Recap form for the data the models produced. If you want to see the full models themselves, then let me know.

 

[hotrod]

I ran one in the early 90's. I really liked it. Side rejection was good. Turned it with a cheapo TV rotor. I would use another in a heartbeat, great antenna. Another local had (still has) a stacked pair. Haven't heard him for years, I think he passed, but his quads are still up.

Can't beat a quad, no matter it's configuration.

If we had todays durable spreader arms and the like, I believe yagi's would be everyone's second choice antenna. Early quads were constructed with flimsy shit that didn't hold up, but the yagi did.

A quad would always be my first choice.

hey duster how was your v quad on local chatting? i know my local reported better results
with his groundplane antenna for local. i do agree a quad would be mu FIRST choice.
checkout lightingantennas.com they make quads.

 

[vkrules]

Oatmeal, here are my Eznec models for a dipole vs the dipole with the elements slanted down at 45* degrees in a V-Quad configuration. I did not tune the the first V-Quad model marked "Not Tuned," and I tuned the last model so you can do a little comparison of a horizontal dipole vs. the V-Quad tuned and not tuned well.

Note: The first dipole was made using only 1 wire. Eznec will not allow any wire to be bent, so I made the 2nd dipole using two 1/4 wave wires, and I fed it in the middle like the 1st model. Notice there is a little difference, but not that would matter at all. In theory it tells us there is a difference, but in real life the difference doesn't matter, just another case of what I seem to claim all the time.

I slant the elements on the 2nd dipole model down to 45* degrees, but I left the dimensions exactly the same, and doing this slanting changes the match at the feed point. Notice this match change in the Source Data report, and there you will see that this slant does make the natural match better, but it is still not perfect, it shows some reactance.

So, I tuned its mismatch out to a near perfect match for the last model noted as "Tuned." This we can see makes for a very good SWR, but this hardly makes a difference in the gain or the angle. Slanting the radials, in this case, does raise the maximum angel a little bit, because the V-Quad is set a bit lower to the ground as a result of slanting.

All the antennas shown here are at 36' feet to the feed point.

I just posted the results in a Recap form for the data the models produced. If you want to see the full models themselves, then let me know.

View attachment 10733

Hey will eznec model a full wave delta loop, like the maco v quad. My software only does square quads.

 

[Marconi]

Hey will eznec model a full wave delta loop, like the maco v quad. My software only does square quads.

Hey Vkrules, you're right square quads are easier. You caused me to realize that the models I reported results for above, were just bending a 1/2 wave dipole into a V shape and that is not a pure V-Quad.

If I made a true quad that would require a matching device, and I can't make a physical gamma in my models. I don't know how to work the electrical matching circuit feature either. I have had some success with series coils as physical inductors on a few models that seemed to work out however.

Do you know why your software will not permit you to make a V-Quad, or is the problem basically that the different angles that are necessary, and not 90* degrees, tends to be confusing?

When we start making wires at angles that are not 90* degrees and are off from the X,Y,Z coordinates noted in the software, you start to get into an all new world of understanding and dimensions suddenly are not what they seem in two dimensions. Just saying.

BTW, what software do you use?

 

[vkrules]

No, I'm using yagi cad, it's fairly basic. Anyway back to the maco. Had one years ago Great antenna.good gain and very low swr. It is horizontally polarized ,so locals will be cross polarized and down in strength as stated earlier.What I found was that it worked well even when mounted low .10 ft off the ground it would outperform a 3 element yagi hands down( the top wire of the loop would be 10 ft higher and this I think is what makes the difference) At 50 ft not much between it and a 3 element yagi. V quads tend to be top heavy.If you suffer high winds, you might be better off with a 3 element yagi.

 

[hotrod]

No, I'm using yagi cad, it's fairly basic. Anyway back to the maco. Had one years ago Great antenna.good gain and very low swr. It is horizontally polarized ,so locals will be cross polarized and down in strength as stated earlier.What I found was that it worked well even when mounted low .10 ft off the ground it would outperform a 3 element yagi hands down( the top wire of the loop would be 10 ft higher and this I think is what makes the difference) At 50 ft not much between it and a 3 element yagi. V quads tend to be top heavy.If you suffer high winds, you might be better off with a 3 element yagi.

iagree with all this. didnt know they beat a 3 element yagi at onlt 10 feet above ground. thats really good.imo the v series antennas are the 2nd best beam antennas. 2nd only to a TRUE quad beam

 

[Marconi]

No, I'm using yagi cad, it's fairly basic. Anyway back to the maco. Had one years ago Great antenna.good gain and very low swr. It is horizontally polarized ,so locals will be cross polarized and down in strength as stated earlier.What I found was that it worked well even when mounted low .10 ft off the ground it would outperform a 3 element yagi hands down( the top wire of the loop would be 10 ft higher and this I think is what makes the difference) At 50 ft not much between it and a 3 element yagi. V quads tend to be top heavy.If you suffer high winds, you might be better off with a 3 element yagi.

Good report VK.

I don't know Yagi Cad, but I've looked at it before, and it looks capable, to me, of doing a triangle design, with wires that aren't parallel or 90* degrees to the default coordinates. The data entry gets difficult however. Luckily, with Eznec it has features that allow one to do those wild angles using a tool that allows normal dimensions to be entered into the tool and the program does all the calculations automatically, and you can also enter the data manually, and use trial and error routines to get the elements like you want...it's all the same but a lot more difficult.

I'm still thinking about modeling the Maco, but I won't be able to match it.

I agree the Quad design may work better low than a Yagi, I've heard that said. I've also heard the Yagi works best if it is mounted higher rather than lower, so I'm not surprised you report that is what you noticed.

If the top wire is horizontal does it radiate horizontal, or does the gamma leg have to be horizontal? If you lean it, so the gamma is vertical, is it then truely vertical, right?

Are you familiar with what goes on inside the round thing that looks like a fat load on the top wire? I'm curious if the wires terminates in that device or is there a coil type transformer inside? I didn't check that out that close. Or, does the load come already installed on the wire, with little to no info in the manual.

BTW, I made a quick check of the Maco Manual, and without really studying, I noticed the 2 x two piece angled aluminum legs that support the top wire looks like they might be about 12' feet long each. I also guess the top might be about that long as well. Is that about right as you recall?

 

[vkrules]

If fed at the apex( up or down) or center of base then its horizontal, Like wise base vertical then it's vertical. Apart from polarity change you can feed a loop anywhere you like. From memory( it's been a long time) the bulb bit is just a termination. loops with large diameter elements are longer that thin wire elements , the reverse of what we see with yagis. So 12'2" should be close for the sides depending on element diameters. I'm going to have a look for the actual specs.

 

[vkrules]

Right, got the manual down. maco are using 11'9 sides on all elements with a top wire of 13'71/2" on the driven.The reflector has a 3 turn coil on the top wire to make the extra( I still don't remember that)

 

[Marconi]

Right, got the manual down. maco are using 11'9 sides on all elements with a top wire of 13'71/2" on the driven.The reflector has a 3 turn coil on the top wire to make the extra( I still don't remember that)

Oh, I get it now. So, that load looking thing is on the reflector wire. Maybe it is a small coil, probably used to add some length like reflectors tend to do...and be higher frequency than the driven element.

This makes perfect sense. I can physically model the load I think. Do you still have your Quad? If so, can you check and get me the dimensions for the wire inside, and maybe how many coils, the diameter, length, and spacing? If not I can fake it I suppose, but seeing as I'll be working with a wildly out of tuned match, it will be hard to tell if the model is close or not.

I have no idea what the natural match will be, considering no gamma is in the model. I can assume the impedance is lower that 50 ohms, however, with some considerable inductive reactance. I'm just guessing though.

I always thought Quad's showed a feed point impedance around 100-140 ohms. I'm assuming the gamma tells us...that is not the case.

What do you think? I don't know that much about Quads, and for sure this particular Quad.

Like I said, I didn't look very close at the manual. I'll have to find it again, and print it out for a reference.

Thanks for your help.

 

[W5LZ]

Marconi,
You were typing with the wrong hand, those fingers got it just backwards. Adding inductance lowers frequency, not raise it.
You're right about a loop typically having an input impedance of about 100 ohms. But, adding more elements to an antenna lowers it's input impedance. The more additional elements the lower that input impedance. A gamma match -raises- impedance, so works fine with an antenna which has a 'too low' input impedance. (Most impedance matching devices found on a multi-element antenna raises it's input impedance.)
- 'Doc

See, that's what happens when you hold that beer can in the wrong hand when typing...

 

[Captain Kilowatt]

I have often wondered why Maco referred to these antennas as quads or even Vee-quads when the proper term for them is a Delta loop antenna or Delta Loop beam. The term "quad" means "four" as in four sided. The Greek letter "Delta" is a triangle just like the Delta loop. Must be one of those CB things trying to capitalize of the reputation of the quad antenna which everyone has heard about. I'll bet back in the day a Delta beam was almost unheard of in 11m circles.

What can I say.......... I am into day four of a 20 day vacation and have plenty of time to nit-pick. Time to go check the smoker. :drool: Company is coming for supper tonight.