Hi Guys
I've bought a Solarcon A99 Antenna for 10meters but I've read somewhere that it will tune down to 20 meters with an ATU, question is do the tuning rings have to be removed first.....yet again I'm sure I have read this aswell.
Any info will be appricated.
Thanks.
M0EEB

I have one for 10 meter. Leave the rings alone at first and snip 6 inches off the top for ten meter. Will work fair on 15, and 17 meter, and somewhat on 20 meter.
Rich

EEB,
20 meters is really "iffy" even with a good tuner...... I can tune to 17 pretty well but, on 20 most of the power is consumed enroute to the antenna.
Rings all the way to the top.....didn't remove them.... :)

Tune rings to get the lowest SWR on 28.400. I think that may be - all the way up - not quite 100% sure.

If still, SWR is too high for 10m, you will have to cut element until SWR is 1.5-1 or less - should be no problem.

If you are using a tuner & plan on using the A99 on other bands - dont cut it shorter - because all the other bands will like a longer element.

This antenna will be best on 10m then 12m, 12m will most likely need tuner.

Fair on 15 & 17m with tuner

Junk on 20m with a tuner.

Any 1/2w dipole at a reasonable height for the band selected will blow away the A99 on 15m & below.

The A99 works fairly well on 10m. Everything else is a compromise. The lower in freq. you go, the antenna becomes more & more LESS effective.

73 K1WJ David

Hi Guys
I've bought a Solarcon A99 Antenna for 10meters but I've read somewhere that it will tune down to 20 meters with an ATU, question is do the tuning rings have to be removed first.....yet again I'm sure I have read this aswell.
Any info will be appricated.
Thanks.
M0EEB

I hope this will help you

The A99 features the Solarcon Twin Ring Adjust-A-Match tuning making it possible to tune the input to the antenna and obtain the optimum S.W.R. over a range of frequencies. Raising the rings raises the frequency and lowering the rings lowers the frequency.

Operates 10 thru 17 Meters with Tuner.
Covers far above and below the traditional C.B. channels for export, commercial and 10 meter ham band use, input 2000 watts P.E.P.
The A99 is a half wave over a quarter wave variable mutual transductance tuned antenna
Comes in three sections, Easy to assemble
Entire antenna radiates - 9.9 DBI Gain
Each antenna individually tested
Meets U.S. Government CPSC shocks hazard standards. Protects up to 14,500 volts
Lightning protected, D.C. grounded. No lightning arrestor or static discharge unit is needed!
2,000 Watt Rated
18-29 MHz Optimal Range
Female UHF Coax Connection
Height: 17.5' Feet Tall
No Ground Needed
:)

Meets U.S. Government CPSC shocks hazard standards. Protects up to 14,500 volts.
NEVER believe statements such as these, UNLESS an independent laboratory has verified (e.g. Underwriter Labs, CA Labs).
Lest we forget that 2 Kansas City amateurs died of electrocution in past 24 months.

w9gb

If you cut 11 inches off the a99 whip you will have a near perfect SWR on 28.400 no need to move the rings they dont adjust that much anyway. Make sure you no longer want to use the chicken band with it because your SWR will not be the best.

VERY interesting discussion.

Several Hams in my area have removed the top "screw-in" fiberglass section of their A-99's and screwed in a standard 102 inch stainless steel whip in its place. When used with a tuner this gives them even more "range" although I have never heard how lower in frequency this lets them go.

Regards, John (N3JPB)

I ran one of the '99s on 10M for years. Recently replaced it with a resonant antenna for 10-11/12/15/17M; no tuner required...max power transfer on all bands.

For single-band operation they're a decent antenna. I worked a lot of DX on 28MHz with mine.

John,

May I ask what resonant antenna you replaced you A-99 with? I too would like to add an antenna to cover those bands, especially if it is not too obtrusive.

Regards, John (N3JPB)

John,

May I ask what resonant antenna you replaced you A-99 with? I too would like to add an antenna to cover those bands, especially if it is not too obtrusive.

Regards, John (N3JPB)
Sure - a modified 4BTV w/ radials. I removed everything above the 15M "stub" and adjusted the 10M section until it resonated around 27.2 MHz. I then adjusted the 15M stub (above the trap) for resonance at 21.2 MHZ. Next, I fashioned a PVC cross-arm arrangement to hold two pairs of #12 stranded bare copper wires, one on either "side" of the main radiator. One of these is cut to resonate at 24.940 and the other at 18.125 MHz. Insulators and small-diameter rope are used to attach and hold the tops of the wires to the cross arms, while the bottom of each connects to the feed point by means of a 1/4" ring terminal. Cross arms are also used at the bottom of the antenna to hold the wires away from the main element.

I used 4 tuned radials per band, sloped away from the attachment point at a 45-degree angle. The converted vertical's base is mounted ~40ft in the air.

There is also a point of low SWR around 29.3 MHz with the finished arrangement, which allows me to work the FM subband area of 10 without an antenna tuner. Of course, my FT-901 doesn't really care about working into a 2:1 VSWR elsewhere on the band.

12, 15 and 17 are below 2:1 throughout, as is 11.

One of the best 10M antennas to come along in years is the Solarcon I-MAX 2000. This antenna is designed similar to the A99 with the same tuning rings, inductance/capacitance coil and fiberglass construction.

The difference being the I-MAX 2000 is 24 feet tall and is a 5/8 wave on 11M. If you actually measure the length of the element, it is really a .64 wave antenna. Just a hair longer than a 5/8 wave (.62). It tunes without a tuner for all of 11 and 10 meters with less than a 1.5 SWR. 12 meters has a 1.7 SWR, and even 15 meters has a 2.0 or less. The 5/8 wave antenna is close enough to a 1/2 wave antenna for 15 meters.

Long term use has proven the I-MAX 2000 to be far superior to the A99. It is even a quiet antenna. With a tuner, I have used it on 17 meters talking to Cuba and Spain with very good results. It borderlines on 20 meters as just OK, but with a tuner I talked to Africa on 20M with the I-MAX 2000. I used to run an A99 with good results. But my I-MAX 2000 blows the A99 out of the water.

If you ever get one of these babies, do not use the ground radial kit if you intend to use it for 17 through 10 meters. Wind a nice choke coil with the coax and mount it within a foot of the antenna feed point. The radials are cut for 11M and will detune the antenna for lower bands. However, if you only use it on 10M, then use the ground radial kit.

Just a little food for thought.

I ran one of the '99s on 10M for years. Recently replaced it with a resonant antenna for 10-11/12/15/17M; no tuner required...max power transfer on all bands.

For single-band operation they're a decent antenna. I worked a lot of DX on 28MHz with mine.

I gave away three of them. To this day I still have no idea what the name of the 10m ground plane is that I am using. It kinda looks like a mini CLR2. IDK but it was free five years ago.:D

One of the best 10M antennas to come along in years is the Solarcon I-MAX 2000. This antenna is designed similar to the A99 with the same tuning rings, inductance/capacitance coil and fiberglass construction.

The difference being the I-MAX 2000 is 24 feet tall and is a 5/8 wave on 11M. If you actually measure the length of the element, it is really a .64 wave antenna. Just a hair longer than a 5/8 wave (.62). It tunes without a tuner for all of 11 and 10 meters with less than a 1.5 SWR. 12 meters has a 1.7 SWR, and even 15 meters has a 2.0 or less. The 5/8 wave antenna is close enough to a 1/2 wave antenna for 15 meters.
...and in the end, it's still a monoband antenna.

Heck, my dummy load is usable on every band from 160M through 1.2 GHz ...

Heck, my dummy load is usable on every band from 160M through 1.2 GHz ...

:D:p:D

ROTFLMAO

One of the best 10M antennas to come along in years is the Solarcon I-MAX 2000. This antenna is designed similar to the A99 with the same tuning rings, inductance/capacitance coil and fiberglass construction.

The difference being the I-MAX 2000 is 24 feet tall and is a 5/8 wave on 11M. If you actually measure the length of the element, it is really a .64 wave antenna. Just a hair longer than a 5/8 wave (.62). It tunes without a tuner for all of 11 and 10 meters with less than a 1.5 SWR. 12 meters has a 1.7 SWR, and even 15 meters has a 2.0 or less. The 5/8 wave antenna is close enough to a 1/2 wave antenna for 15 meters.

Long term use has proven the I-MAX 2000 to be far superior to the A99. It is even a quiet antenna. With a tuner, I have used it on 17 meters talking to Cuba and Spain with very good results. It borderlines on 20 meters as just OK, but with a tuner I talked to Africa on 20M with the I-MAX 2000. I used to run an A99 with good results. But my I-MAX 2000 blows the A99 out of the water.

If you ever get one of these babies, do not use the ground radial kit if you intend to use it for 17 through 10 meters. Wind a nice choke coil with the coax and mount it within a foot of the antenna feed point. The radials are cut for 11M and will detune the antenna for lower bands. However, if you only use it on 10M, then use the ground radial kit.

Just a little food for thought. Yeah had 2 imax 2000 good antenna poor strenth they both broke in half right above the second section. Also had 2 friends both had imax 2000 and again they broke in half just to flimsy I would never buy another one. Comparing the a99 to the imax not that big of a difference noticed in my location.

...and in the end, it's still a monoband antenna.
Heck, my dummy load is usable on every band from 160M through 1.2 GHz ...
LOL Yep that's true, but the I-MAX 2000 actually works very very well. Always good 20 to 40 dB signals or higher on 17 through 10 meters. I haven't heard a signal yet that I couldn't hold a QSO with. I somehow doubt your dummy load will do that.:D




Yeah had 2 imax 2000 good antenna poor strenth they both broke in half right above the second section. Also had 2 friends both had imax 2000 and again they broke in half just to flimsy I would never buy another one. Comparing the a99 to the imax not that big of a difference noticed in my location.

WOW! That really surprises me to hear that. I must know 30 different people who are as happy with their I-MAX 2000 as I am. Some have been up for years surviving the Nor-easter mini winter hurricanes and big summer thunderstorms with high winds. Mine still stands tall. Read the dozens of reviews on eham.net, and hear nothing but high praise for this antenna and no broken ones. I wonder if there were a bunch of bad ones distributed in your area, because that is very unusual.

When switching from the A99 to the I-MAX 2000, quite a bunch of us noticed a big improvement in signals both TX and RX. And much less QRM for a vertical.

It kinda looks like a mini CLR2.
And speaking of that, whenever the threads about the A99 pop up I always wonder if anyone has compared the performance of the A99 or the Imax to the older Hygain CLR-2, the Antenna Specialists Super Magnum, or the Avanti Astroplane. I suppose since they are much older antennas they are harder to come by to use in order to get a comparison. Anyone with experiences to share?

If you do have the GP kit, you can experiment with different radials to bring the 99 closer to resonance on multiple bands using a tuner.
One radial for 20m one for 17m,10m etc, all on the same mounting piece.

LOL Yep that's true, but the I-MAX 2000 actually works very very well. Always good 20 to 40 dB signals or higher on 17 through 10 meters.
Per chance, what is a "20 to 40 dB signal"?

20 to 40dB out of the noise, gain over isotropic, ?

Enlighten us, please.

Sure - a modified 4BTV w/ radials.

Thanks for the detailed information. I will be reading all that several times. I will PM you after I digest what you wrote if you don't mind too much.

I am just getting back into Ham Radio after 48 years away so I am back into re-learning about antenna theory.

Thanks again.

John (N3JPB)