Base BJ radionut and his AR-10 Ringo

[Marconi]

Not GOLD Plated or Fancy Hype but a very practical, functional antenna...
http://www.cushcraftamateur.com/Product.php?productid=AR-10

Had one up for years above a 3 element 10m yagi...work pretty damn well...easy as hell to tune...and won't break the bank...Lots of guys give the Ringo's a bad rap...but you get them up and they work for years.
All the Best
Gary

Gary, I took your comments above from the thread on the Imax an made another thread to ask my questions about your Ringo.

I've tried modeling this antenna, but there are too many dimensions missing in the link above to be sure.

What is the space between the brackets?

Can you describe the details for the tuning stub? They show a length. But how does it works to tune the ranges noted?

It doesn't even show the length and diameter dimensions for the mounting bracket noted as the base assembly AA. It does show BB throught EE at 48" inches each which = 192" and then the overall length chart shows the overall length is 192" at the mid band. I don't get it...the base assembly does not appear to be included in the overall length except in Fig 3.

There are other dimensions that are important as well if a model is to try and even get close.

Maybe you help me with this?

 

[BJ radionut]

Marconi: get with you after 3 days of HAMVENTION...73
The mast mounts inside the bottom just below the Tuning ring...which to me seems like a Gamma match...not sure off top...what the diameter truly is maybe 8 inches OD...adjustments with tuning ring and overall length...once I found the the X=0 ... slight movements on ring stub...I adjusted frequency by adjusting length...pretty quick set-up...
Later
All the Best
Gary

 

[HomerBB]

The overall diameter of the current AR10 is 13". The older ones were smaller. About 10" diameter. The lengths for the vertical start at the top of the insulator, not the overall antenna length.
The stub is 16-5/8" long.
1.5" is right for the space in between the ends of the ring.
I think the bottom is about eight inches, too.
I'll measure it.

 

[Marconi]

Marconi: get with you after 3 days of HAMVENTION...73
The mast mounts inside the bottom just below the Tuning ring...which to me seems like a Gamma match...not sure off top...what the diameter truly is maybe 8 inches OD...adjustments with tuning ring and overall length...once I found the the X=0 ... slight movements on ring stub...I adjusted frequency by adjusting length...pretty quick set-up...
Later
All the Best
Gary

When you get time Gary.

 

[Marconi]

The overall diameter of the current AR10 is 13". The older ones were smaller. About 10" diameter.

Thanks, Homer. Based on the current manual that Gary posted above...I estimated the ring diameter was maybe 14" in diameter with each bracket about 7" inches long. See note with such a 7" inch dimension measuring between 90* and 180* degree points on the ring. I wonder why CC even added this measurement...the ring is not adjustable.

The lengths for the vertical start at the top of the insulator, not the overall antenna length.

I agree Homer, but from here on I'm just guessing. There are 5 sections to the exposed vertical radiator including the base assembly which probably comes preassembled and shows no dimensions.

With 4 inches of overlap per tubes BB,CC,DD = 132" inches. Assuming AA from the isolator up is 48" inches exposed, I get 180" inches from the insulator to the top of DD. This allows for EE = 12" inches of exposure to equal 192" inches overall for the mid-band frequency which I choose to model. If successful I would then scale the 10 meter to 27.205 MHz.

The base assembly could also be 48" inches with about 12" inches down inside the base mount which would make it 36" inches exposed. This would make the tip EE = 24 inches exposed instead of 12" inches as I noted above.

There are other possible combinations here that would matter somewhat if modeled to specs, which I doubt are easily available.

The stub is 16-5/8" long.

I see that dimension in the manual, but I see no details of its characteristics. I assume it is an inductor, but the type of coax might make a difference. I also assume it is a closed-end loop.

1.5" is right for the space in between the ends of the ring.

I will use this dimension for now.

I think the bottom is about eight inches, too. I'll measure it.

My ideas above consider the mounting bracket to be 12" or more. I see the mast going up inside this bracket that might be 1.25" inches in diameter, but I'm not sure how the tip is isolated from the radiator that is also inside. There are some words in the manual about this setup inside, but I do not have this point clear in my mind regarding how to model. Best guess is to just use a space between the mast and the antenna PERIOD. This is a similar problem I have with modeling the Maco V-58 and my Wolf 50_11M knockoff of the Ringo. I don't think I can physically model an object inside of another object...like a capacitor.

You guys don't have to go to any extra trouble on my account, this design seems difficult at best...even if I had the antenna here on my workbench. There are a lot of little dimensions that might be necessary to get this physical matching setup to work like the real antenna...if that is even possible. I've tried it before and was not successful with the Maco V-58 and my Wolf 50_11M, and Cushcraft never makes thing easy.

I will add however, that my Wolf knockoff of the Ringo never showed a good match and worked best with 1.70 SWR using SSB at the top or 11 meters. Before I broke on me I repeatedly got very good unsolisited reports locally on this antenna and during the short time I worked it I always seem to show RX signals as good or a bit better than some of my other CB antennas. I never worked it in any comparison testing I've looked back on, but I was impressed with how it worked.

 

[HomerBB]

I'll try to get you photos and measurements this afternoon.
The ring is the only inductor.
The stub is RG8 coax. The overall length is as above. The inside center core wire and the dielectric extend the full length. The coax braid is trimmed back from the end 1/2". It is sealed and capped over.
I will get you a capacitance reading on it this evening.
I have one I am trying to scale to 6m.
It is an older one from Cushcraft. The newer ones are from MFJ.
That ring diameter is center to center of the ring tubes. Length is 40.885" (roughly 40-7/8") when each half is is assembled.

 

[Marconi]

The stub is RG8 coax. The overall length is as above. The inside center core wire and the dielectric extend the full length. The coax braid is trimmed back from the end 1/2". It is sealed and capped over.

So, it is not a loop, and the stub shows no continuity at the connector at the top of the stub? So, Gary is right this device acts like a gamma match.

I will get you a capacitance reading on it this evening.
I have one I am trying to scale to 6m.

Will you be scaling the stub length and wire diameters as well?

It is an older one from Cushcraft. The newer ones are from MFJ.

Do you have a manual for the older AR-10?

That ring diameter is center to center of the ring tubes. Length is 40.885" (roughly 40-7/8") when each half is is assembled.

So, the ring is close to 13" inches and the brackets are a bit over 6.5" inches long.

My Wolf 50_11M attaches the same way and the mounting bracket is heavy wall aluminum...but even so the short screw only has a couple of threads and it failed at this point over time.

My antenna is supposed to allow the radiator length to move up and down at this point in the insulator for fine-tuning. The idea is...this way you don't have to lower the antenna all the way down to adjust the tip element. That said, however, the idea fails because this connection point is weak and fails a noted.

I suggested that Eddie Wolf add a think nut to this point to give this set screw more threads to secure the insulator. This idea worked for a while but the screw buggers the insulator up inside the base mount tube and after a while in the wind and weather there is no way to get the insulator capacitor to move again...it is stuck.

Thanks for the info.

 

[HomerBB]

In the attached photos you will see I have not reduced the stub from RG8. Only its length. I am not cutting the original stub (capacitor) as it isn't mine. Made my own.
This antenna uses a simple parallel capacitor/inductor tuning network.
I do not have an older manual.
The capacitance of the stub is 44pf according to my MFJ-259B.
You can see the lower mount tube is 7" long, from the top of the insulator is 8.5" long.
This antenna permits adjustment of length at every tube connection but not at the bottom like your Wolf.
I am having difficulty tuning this antenna. I am going to have to disassemble and clean it up first.

 

[HomerBB]

This matching network for some of my EFHW antennas is another version of what you are dealing with - tapped ring = tapped coil (inductor), plate capacitor = coax capacitor in parallel with each other.

 

[vkrules]

Hi Homer, risking that I might be stating what you aready know but ,the insulated tube inside tube mount also adds capacitance across the feedpoint and is critical to the match.
Back in the seventies (broke kid at the time) I duplicated a friends ringo. All the external diamentians matched but I forgot to duplicate the length of the tube inside the insulator couldn't get the swr below 2 .It took me 3 weeks to work it out!
Also clean the insulator and inspect for cracks.Moisture can make them impossable to tune.

 

[HomerBB]

Hi Homer, risking that I might be stating what you aready know but ,the insulated tube inside tube mount also adds capacitance across the feedpoint and is critical to the match.
Back in the seventies (broke kid at the time) I duplicated a friends ringo. All the external diamentians matched but I forgot to duplicate the length of the tube inside the insulator couldn't get the swr below 2 .It took me 3 weeks to work it out!
Also clean the insulator and inspect for cracks.Moisture can make them impossable to tune.

I built one, too and figured it out. It is part of the system mainly because it has no choice...
I will check the condition of the insulator.
When I built my homebrew EFHWs I managed to avoid as much stray capacitance as I could. Kept tuning simpler it seemed.

 

[357magnum]

Thanks to all posting on this thread , I just found an Ar-10 in the trash and needed some specs to go on because the one I have Is close but no cigar I believe it was used on a ham frequency because it's doesn't seem quite long enough for 11m . I always liked these antennas " Back in the day" . Now time to clean it and get it right ! Many Thanks again ! 73 and God Bless , Leo

 

[Marconi]

I am having difficulty tuning this antenna. I am going to have to disassemble and clean it up first.

Homer, did you get your antenna working?

Thanks to all posting on this thread , I just found an Ar-10 in the trash and needed some specs to go on because the one I have Is close but no cigar I believe it was used on a ham frequency because it's doesn't seem quite long enough for 11m . I always liked these antennas " Back in the day" . Now time to clean it and get it right ! Many Thanks again ! 73 and God Bless , Leo

357, I read here that you liked this antenna "back in the day." Do you think that Cushcraft made this antenna for 11 meters too, and if so can you give me the dimensions they published?

Thus far with the help of Homer and BJ, this end fed 1/2 wave model using Eznec is still No-Way-No for me.

I have three iterations for the ring diameter at 11 meters, small, med, larger...and thus far I'm like Homer...the model does not show any sign of tuning well.

Before you guys get all excited, this model could have an issue that I'm over-looking or over-thinking...based only on my understanding of the reported dimensions I have so far.

 

[HomerBB]

I have not had the time to clean it up, yet.
Even the homebrew I made was difficult to tame, but that could have been me not duplicating it properly.

 

[357magnum]

Marconi , I will do some research on it . I remember in the 70's a lot of Op's were using a " Ringo " on 11m . Not sure this is the same one that just has a section missing . But I also saw a lot of them similar to these on roofs in the hay day of Cb . When I find something I will send it to you via PM . 73 and God Bless , Leo