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Ringo Ranger Problems
In article ,
John Ferrell wrote: I cannot imagine what your problem is with the 2 meter CushCraft Ringo Ranger. I have had the same one in service off and on since the late 70's. Easy to mount, easy to match, physically durable, priced real close to the cost of the aluminum. The J-Pole is popular now days but is not near the performer that the Ringo is. I have both! The Ringo on a tower is not a good idea because it brings up too many repeaters on a given frequency. Bad operating manners! As far as the 12 element CushCraft Yagis are concerned I have a 440 & 2 M models and have found them to work just like the modeling programs indicate. There will be a "lump" on the pattern that is not shown in the model, presumably radiation from the Gamma match. As I understand it, the basic Ringo antenna is a half-wave, end-fed vertical dipole. A gamma loop at the bottom serves as the impedance matching element. The basic J-pole is fundamentally quite similar... it's a half-wave vertical dipole, end-fed. The common versions of J-pole use one or another variant of a shorted quarter-wave stub section as an impedance match. These two antenna types should, in principle, have very similar radiation patterns (they're both half-wave radiators) and can have similar problems with pattern-disturbing "RF on the mast" and "RF on the feedline" (they're often grounded to the mast, and fed from a 50-ohm feedline without a choke). In some installations, the "RF where you don't want it" condition could cause the antenna's pattern to squint in directions where it doesn't do you all that much good, and have a weaker signal directly out towards the horizon where most of the repeaters probably are. In other installations (where the feedline or mast presents a high or highly reactive impedance) you wouldn't notice any problem. The Ringo Ranger is a higher-gain antenna, with two vertically-stacked radiating sections and a phasing stub between them. It looks to me as if the two sections are 5/8 wavelength or a bit more. You'd get several dB more gain towards the horizon with this configuration, than you would get from a J-pole or an original Ringo. The Ringo Ranger has no decoupling from the mast or feedline, and can suffer from the same sort of pattern-squint as the Ringo and J-pole. The Ringo Ranger II adds a decoupling section (a length of feedline and a set of decoupling radials) which is supposed to prevent this problem, and it would probably have the cleanest and sharpest towards-the-horizon pattern of any of these antennas. -- Dave Platt AE6EO Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
#2
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Thank You / Thank You / Thank YOU VERY MUCH!
I can make a loop out of some copper tube and I can use a old piece of RG 8 for the stub match and I have enough aluminum tube from another Ringo to make the mast 18' long..... All I need to do now is take down what I have and modify it and put it back up. THANK YOU! Dummy ME! - I could have bought a used antenna analyzer at a hamfest today for $50.00 - MFJ that had no digital display and no UHF and NO POWER SUPPLY and no instructions. I was told that I could have used it with a transceiver, turn the knob until it zero beats the frequency of the receiver and then use it to tune the antenna. I probably messed up! Then again - if it was $50.00 and didn't work and could not be repaired - it would have been $50.00 that could have been applied towards another antenna. This is what happens when you try to help someone and when you try to give something away to a friend.. It always happens that something is not right and that when it does not work as intended - even if several years later - I end up being the bad guy. In fact - the Ringo listens real well - it just doesn't transmit - because the impedance / reactance is wrong. I could have bought a good antenna analyzer last year for $85.00 and did not because a friend of mine wanted it and bought it for $65.00 I'm learning that amateur radio is a lot like stock car racing. The only friends you have is the ones you brought to the track with you! Once the Green flag falls - all agreements are off and it is a free for all. |
#3
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Ringo Ranger Problems
On 9/9/2012 7:36 PM, Channel Jumper wrote:
I could have bought a good antenna analyzer last year for $85.00 and did not because a friend of mine wanted it and bought it for $65.00 I think they are overrated.. I've never needed or owned one so far.. |
#4
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Quote:
With a digital display it is as simple as putting the antenna together on the ground, sticking it on a pole someplace, using a feed line that is as short as possible - less then 1/4 wavelength is desireable when possible - I know at higher frequencies this is hard to do. Turning on the Analyzer and reading the input. Using a old style analyzer isn't as simple when you do not know the exact frequency you are tuning to... So in the long run - I probably saved myself $40 - $50.00 A stub match question I forgot to ask is - should the end of the stub match at 1' 8 inches long be shorted on the end or open... The web calculator I used said the Stub would be short if it was shorted and would be long if it was not - but that if it was not shorted you run the risk of the stub trying to radiate the power applied... http://www.qsl.net/va3iul/Impedance_...e_Matching.pdf |
#5
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Another broadband matching approach may use a tapered line transformer with continuously varying
characteristic impedance along its length (characteristic impedance varies continuously in a smooth fashion). In this case, the design obtains reflection coefficients lower than a specified tolerance at frequencies exceeding a minimum value. · The required length of the taper section should be about 0.5 to 1.5 of wavelength. A different narrow-band approach involves the insertion of a shunt imaginary admittance on the line. Often, the admittance is realized with a section (or stub) of transmission line and the technique is commonly known as stub matching. The end of the stub line is short-circuited or open-circuited, in order to realize an imaginary admittance. A second narrow-band example involves the insertion of series impedance (stub) along the line. |
#6
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Ringo Ranger Problems
On 9/10/2012 3:06 PM, Channel Jumper wrote:
A stub match question I forgot to ask is - should the end of the stub match at 1' 8 inches long be shorted on the end or open... Open. It's being used purely as a capacitor. |
#7
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Ringo Ranger Problems
In article , NM5K wrote:
On 9/9/2012 7:36 PM, Channel Jumper wrote: I could have bought a good antenna analyzer last year for $85.00 and did not because a friend of mine wanted it and bought it for $65.00 I think they are overrated.. I've never needed or owned one so far.. I had a plain Two Meter Ringo back in the 70s, before they came out with the "Ranger" versions. It worked well, but gain claimed was probably DBi rather than DBd. I also have three generations of MFJ antenna analyzers. I don't know if they are overrated, but they are very handy. They save a lot of time compared to using a transmitter and SWR bridge to set up an antenna. As I understand it, they work just like the typical "reflectometer" SWR bridge where you set forward power to full scale and read reflected power on an SWR scale. Their VFO has its output held constant over the frequency range, calibrated for the equivalent of the SWR bridge's full scale setting. The early version Channel Jumper mentioned, probably had a frequency scale printed on the face. For critical settings, either a counter or a calibrated receiver would be needed. Later versions have a counter built-in, and the latest also displays antenna data on the LCD display. Fred K4DII |
#8
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Ringo Ranger Problems
On 9/10/2012 1:46 PM, Fred McKenzie wrote:
In article , NM5K wrote: On 9/9/2012 7:36 PM, Channel Jumper wrote: I could have bought a good antenna analyzer last year for $85.00 and did not because a friend of mine wanted it and bought it for $65.00 I think they are overrated.. I've never needed or owned one so far.. I had a plain Two Meter Ringo back in the 70s, before they came out with the "Ranger" versions. It worked well, but gain claimed was probably DBi rather than DBd. If they rated a ringo using dbd, it would be zero.. Which doesn't look too good in the ad's.. :| So they use dbi to make for manlier gain figures.. I also have three generations of MFJ antenna analyzers. I don't know if they are overrated, but they are very handy. They save a lot of time compared to using a transmitter and SWR bridge to set up an antenna. Dunno, I'm pretty danged fast using just an SWR meter. But I already know what to expect, how to quickly know if I'm long or short, etc.. All the analyzers do for me is verify what I already know from looking at the SWR meter, which in my case is built into the radio, assuming I'm on the Icom. :/ I like not having to carry extra gadgets.. |
#9
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Being Long or Short is not the problem - if it was simple vertical with a ground plane with no loading coil - like a whip on a automobile - yes - you would be right.
But when dealing with a Ringo - which uses a ring to adjust the capacitive / inductive and also uses a tuning stub match - each part of the antenna works against each other.. Even now, the antenna on the VSWR Bridge shows a 2:1 match! But I figure the Ring is probably 9 inches too shot - if the ring is 7.5 inches in diameter and needs to be 10 and the stub is too short - if it needs to be 18 inches long and is only 6.... The Antenna Analyzer would tell me the Resistive / Reactive components and all I would have to do is match them and it would work on any one frequency. This is the problem with the Ringo - why it is not broad banded. The main use where I live was by people who were installers of LMRS equipment that sold them along with a radio to fire companies and ambulances.... |
#10
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Ringo Ranger Problems
On 9/10/2012 7:40 PM, Channel Jumper wrote:
Being Long or Short is not the problem - if it was simple vertical with a ground plane with no loading coil - like a whip on a automobile - yes - you would be right. No problem even with loading coils. Or when using the various matching systems. They all act fairly predictably. But when dealing with a Ringo - which uses a ring to adjust the capacitive / inductive and also uses a tuning stub match - each part of the antenna works against each other.. Even now, the antenna on the VSWR Bridge shows a 2:1 match! Sure, it needs more inductance. But I figure the Ring is probably 9 inches too shot - if the ring is 7.5 inches in diameter and needs to be 10 and the stub is too short - if it needs to be 18 inches long and is only 6.... For a 10m ringo 18 inches would be about right with it tapped about halfway. I think one I made used about a 20 inch dia turn. But I didn't need all of it. The Antenna Analyzer would tell me the Resistive / Reactive components and all I would have to do is match them and it would work on any one frequency. Sure.. But I can do it by sense of smell.. Plenty of practice.. :/ This is the problem with the Ringo - why it is not broad banded. The main use where I live was by people who were installers of LMRS equipment that sold them along with a radio to fire companies and ambulances.... It should have about the same bandwidth as most any other half wave. I've never noticed them to really show any less bandwidth than other designs. But then again, I'm not sure what you mean by not broad banded. That could vary depending on expectations. |
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