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Reviews Categories | Antenna Tuners | MAXX-COM AUTOMATIC ANTENNA TUNER Help


Reviews Summary for MAXX-COM AUTOMATIC ANTENNA TUNER
MAXX-COM AUTOMATIC ANTENNA TUNER Reviews: 14 Average rating: 2.9/5 MSRP: $$395-$595
Description: 100% Solid State Construction. No moving parts to break or wear out. MAXX-COM is the most compact, simple, and efficient antenna tuner available! MAXX-COM matches in 1/1200th of a second. 150 - 2000 Watts. .1 - 250 MHz. VSWR is less than 1.5:1 on all frequencies.

Product is not in production.
More info: http://www.maxx-com.com
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N1EA Rating: 0/5 Mar 13, 2005 08:45 Send this review to a friend
Trash - over priced  Time owned: more than 12 months
I had one on a ship. It was a terrible radiator, but the company bought one. One day we failed the FCC annual test on 2182 kHz (think 160 meters for a comparison). I took apart the Maxx-Com "tuner".

Inside was a single Dale Precision resistor 50 watt type and a small transformer made of teflon wire.

The reason we failed the inspection? We could NOT communicate with a ship that we could visually see with our eyes on 2182 kHz.

I replaced this with a marine whip - and it worked much better.

73

David Ring N1EA
 
K7SUB Rating: 5/5 Nov 16, 2004 06:16 Send this review to a friend
Outstanding  Time owned: more than 12 months
It took a little playing with antenna configurations, but the "tuner" does exactly what the specs say it does. Because my loop is very close to the ground, the take-off angle on the lower frequencies is Near Vertical which works great for local nets (300-400mi) on 75 and 40M. One the upper bands the angle changes and the loop works normally.
It is pure pleasure to have a no-fuss no-muss "tuner" that will match on any frequency you put it on automaticly without any worries.
Whatever is inside--it works, and it works well!
 
KI7YY Rating: 5/5 Jan 18, 2004 06:58 Send this review to a friend
Don't Laugh!  Time owned: 0 to 3 months
I just recently was given a used Maxxcom Tuner to check out and have been very impressed. Having heard all the talk about it being "just a resistor" it was fun to play with. It matches everything I've tried it on. The antenna I'm using now for HF at my temp. QTH is a 100 ft. doublet tuned with an sgc 239. With the Maxxcom the signals seem louder because of the noise threshold being lower. None of the stations routinely worked notices any difference in my signal strength. The thing probably is a big resistor or other such thing ...but it works. The companies website says 80% efficient, so there is obviously some loss involved. The workmanship is excellent and it does what it claims to do. A real 5.
 
ZL1WDC Rating: 5/5 Dec 2, 2003 18:12 Send this review to a friend
Not just a toy!  Time owned: 0 to 3 months
After all the controversy about Maxx-Com tuners and the debated infamous QST review (which I still donít understand) it is time to put it all to rest. Do yourself a favour and take time to read this completely; try to be objective!

I am a radio eng by trade and my life used to be about radio. Fortunately for my wife it is now a hobby only. I worked mostly on VHF & UHF systems but dabbled in HF. I have been active in Ham Radio since I was 14. I am now 38 and I have seen some fascinating things occur with RF over the years that at times could not be explained. During this time I have tracked radio interference from un-believable sources and could not understand some of the causes of this interference to this day. My point from all this is? That there is still a lot to discover about RF as there is about our world. If we spent as much time and effort on the "battery" as we did on the combustion engine, we would know ten times what we do today about the storage of electricity and probably have mostly electric cars in our world instead.

I imported a Maxx-Com 200D for a few hundred dollars extra (due to freight costs) over its stated price and still found this to be an acceptable price, infact I would say its cheap for what it does. The Maxx-com 200D is a military/commercial model tuner that is a bit dearer than the miniature models that operates to 30Mhz only. This model handles a much higher frequency range of up to 250Mhz and handles 200watts. It looks pretty much like the picture at the top of this review section, but white with two insulators instead of one. (See www.maxx-com.com)

The Maxx-com 200D is actually an antenna matcher that is used at the base or feed point of an antenna, not back at the transmitter like that of conventional tuners. Tuners match the whole system, the coax and the aerial. The Maxx-com 200D allows the coax to operate at its intended impedance of 50 ohms, which I know from experience, reduces a certain amount of loss in the cable. For example RG58 coax experiences about 1db of standard loss per 100ft of cable and RG213 is about 0.6db per 100ft. You can double this figure when a tuner is used to significantly match both the line and aerial to a desired freq. Most antenna systems are less then desirable because we as Hams try to compromise between size, length and ugliness to accommodate our surroundings such as our house, trees and neighbours. Other than those who are blessed with a 1/2-acre paddock, very few people have the room to erect large antennas and therefore never really have the antenna they desire. Nor is the one they do have, resonant on all bands properly. I have a 5 band trapped vertical that resonates on 5 bands from 80m thru 10m. The lower the band, the smaller the resonant bandwidth and the eventual requirement of a tuner to operate the rest of the band effectively. With a trapped horizontal dipole, I have slightly less noise and slightly improved RX & TX signal reports on 15 & 10m bands over the vertical (quite subjective since I have little space and trees). I would be lucky if this dipole is 10 metres of the ground due to my constraints but I am on a hillside facing south and tend to have excellent reports for the system. I do however get alot of broadband noise, which I liken to a power noise that can hit 5 or 6 on my S meter on 80 or 40 m bands. It doesnít help that I also face towards the most industrial side of my city and a harbour from which an airport sits directly across from me. Needless to say I get allsorts of noise at varying times of the day.

Enter the Maxx-com 200D. Strung up simply no higher than 15 feet of the ground at the feed point and using two roughly cut 35ft pieces of copper wire sloping from each insulator to about 7ft from the ground. I did this on purpose because it is the min recommended length to use by Maxx-com. At 15ft high I can work on the aerial easily while testing. Being on the hillside I still obtain reasonable results. After stringing this up in less than 10 minutes with crimped ends and connected to about 20feet of RG58, my first thought was to test the SWR. It seems to be something we hams just canít get over having, a low SWR! Unbelievably it was very low across all bands from 160m thru 10m. I think one WARC band was about 1.5:1 but most were under 1.2:1! I quickly noticed that the received signals by my FT897 were always there across the bands. I wondered how good they really were compared to my other aerials, so I ran to the other room and fired up the FT897 again on the other two aerials. Checked one particular station on both aerials as being within 1/2 S point of each other and then ran back to the Maxx-com set-up...the signal was about 2 S points lower, but it was infinitely clearer...the S/N ratio was also a huge improvement. I checked the noise floor across the bands and I was amazed that I could see very little other than about 1 S point on all bands other than 80M which was sitting at about S 5. I had never (in this house) experienced such a low noise floor! I tried other bands, same thing occurred. Sometimes the difference in RX strength was un-noticeable with a signal, but most of the time, the S/N was far better. I mean if you could quantify this, I would say this; take away the noise on normally feed aerials such as my vertical & trapped dipole and there would be a signal of maybe 2-3 S points only in signal, being half what would normally show on the meter because of noise. I played for hours trying to find the tunerís drawbacks and faults. On transmit I found at 100w RF out, the 200D was marginally warm and my reports were as good as they had ever been. After a lot of testing and thought, my best guess was that I was loosing a max of 20% of my RF through this system. It wasnít enough over the other very similar aerial systems I had to quantify a difference in TX signal strength. Infact, I would fear to say that what the Maxx-com looses in RF, it makes up for where we normally loose it anyway, in a manual or auto tuner and the un-matched coax of the system. I estimate about a 1.5-2db loss in the tuner, balun and un-matched feeder on a reasonable system. This is probably more if not similar (depending on radiator length) as the Maxx-com tuner in a basic min length dipole. There was no advantage in my opinion having a trapped dipole twice as high that I had to tune on each bandÖit was a disadvantage!
The only minor drawback with this Maxx-com 200D is that it does not work well if the antenna is less than about 23 ft in length; this is because the 200D relies on a radiator load, the larger the load the better the radiation and more efficient the 200D becomes. Small radiators cause a lot of the RF to re-circulate back through the network in the 200D. It works using smaller radiators, just not as well. Maxx-com recommends a min of 35ft and suggests use of a 100ft dipole, which I see no problem doing with only wire (no traps) in an inverted V set-up. The longer the radiator, the better this matcher works. Another thing to remember; this device is a non-resonant grounded device, so, it works better on non-resonant lengths of wire. Use lengths that resonate in-between bands you desire for best results. The great thing about this unit is that it can be used QUICKLY with no fear. Field days!!! You could in an emergency, match it to a balustrade on a boat or a long random length of wire and earth very quickly without fear of it not working or blowing up; to me that is life saving. It is quite honestly, the most remarkable piece of RF equipment I have ever used and I have hardly begun testing it.

Remember, just because we canít see inside it and we donít know the Schematic, doesnít mean it isnít real. I read so many things from Hams like this: "What is this thing, can it be real? I have seen no diagram on it anywhere so how can it work?" I mean honestly, how pathetic! Whatís better than a patent? Stopping people from copying it! Thatís clever. X-raying it?? I canít imagine what they were doing or said about it, but this is RF, not logic and there is no phantom resistor sucking up the power either or it would have over heated within minutes! There is something going on inside it and its something probably very fundamental that has been over looked for years in RF. Put it this way, if I have been tricked, then this is the best trick I have been subjected too, as I am not ware of it! In saying this, I am happy to stay in this illusion from now with my new antenna matcher! Personally itís worth the money to use such an idea, even if it was a cheap and simple product to make. After all, we do that in everyday life; pay for what we donít understand or canít make ourselves.
I love my matcher and for any ham or commercial radio tech that wants a neat piece of gear that eliminates a conventional tuner and some noise for wide band general use, or even a dedicated set-up; this is your toy!
 
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