| N7DKK |
Rating:  |
2003-10-23 | |
| What a hot little box! |
Time Owned: 0 to 3 months. |
I put up a delta loop for 40-10 and the VSWR was just a tad over 3:1 on most of the bands. The internal tuner in my ICOM 746 was only able to match it on 20 & 10 meters.
After reading the reviews here, I invested in an AH-4. Cut the 50 ohm connector off of the loop coax and stripped it back. Hooked the center conductor to the insulator on the AH-4 and the braid to the ground on the AH-4. No mention that this unit was able to work with an unbalanced feedline.
Did it ever work! A perfect match to the transceiver on all bands 80-6! 160 didn't quite make it.
It tunes QUICK! Emits only 350mW (I believe) when tuning and remembers so it's REALLY fast the next time!
At this point I would have to say that the ICOM AH-4 is perhaps the best money I have spent on ham radio equipment.
It's extremely well engineered, constructed and priced correctly. If you're considering a remote auto tuner this one should be on your short-list. |
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| N5LHD |
Rating: |
2003-09-13 | |
| Perfect for Mobile Operation |
Time Owned: 6 to 12 months. |
I installed an Icom IC-706MKIIG with the AH-4 auto antenna tuner using a 102” stainless steel whip mounted on the rear bumper of my 2002 Chevrolet 4x4 pickup. The AH-4 was bolted to the underside of the truck bed just above the spare tire. I felt the spare tire would help shield the tuner from road debris, rain, mud, etc. I used a 20” length of #8 AWG high voltage wire (15KV+) from the tuner to the feed point of the whip. I was able to tune all bands except 15mtrs. After re-inspecting my installation I discovered a queer length of coax between the radio and the AH-4. I shortened the coax length 26” and it now tunes quickly and easily from 3.5 – 54Mhz.
I admit that it is very nice to be able to move from band to band and tune the antenna with just a touch of a button. My previous antenna was a Texas Bugcatcher that required me to stop my vehicle, get out and go change coil taps. The Bugcatcher was also 14 ft. tall with a 16” capacity hat, and it was constantly getting beat-up on freeway underpasses, low hanging lights, tree limbs, etc.
The performance of the AH-4 and whip is as follows: 20mtr through 6mtr is great! Working DX stations is easy. Contacts over the last three months include; 4 Russian, 2 Japanese, 7 Central and South American, 4 European, many Canadian, and 1 Hawaiian stations.
However on 40mtr and 80mtr the system is very inefficient. On 40mtr you can talk to anyone you can hear. Average signal reports are 3 or 4 S-units above the noise during the day but much harder to make contact at night because of the broadcast interference. On 80mtr this is a real testament to the other stations receiver! Most people I have made contact with ask me “Repeat your last transmission OM the static crash took you out”.
I have made side-by-side comparisons between the Bugcatcher and the AH-4 using the whip. Yes, hands down the Bugcatcher outperforms the AH-4 and whip combination on any band. However there was little difference in signal strength between the two antennas from 20mtr though 10mtr with the edge going to the Bugcatcher. On 40mtr the Bugcatcher was much stronger, and on 80mtr I was able to carry on a QSO with any station I heard – not so using the AH-4 and whip combination. Interesting is the fact that I could not tell any difference in receive signals on any band between the two antennas.
I later added an additional 48” mast and a 16” capacity hat to the 102” whip and tried this same test again. AMAZING results, the performance of the AH-4 with 150” antenna and capacity hat was equal to the Bugcatcher! The only drawback is now I’m back to the same problem… constantly hitting on freeway underpasses, low hanging lights, tree limbs, etc.
Bottom Line – I like the AH-4 and 102” whip setup. The antenna does not draw attention to my vehicle; I can drive anywhere I want without antenna damage; Performance vs. package size is unbeatable; Modest cost for total HF mobile coverage.
Mark – N5LHD
Houston, Texas
n5lhd@swbell.net
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| N4VAS |
Rating: |
2003-08-14 | |
| Great tuner |
Time Owned: more than 12 months. |
I've been using my AH-4 for about 1 year now with the Icom 746 and a 255' dipole at about 50' up. I was having a little trouble getting it to tune 160 meter band so just for the heck of it I installed a Ten Tec 4:1 balun and now I can tune 160 thru 6 meters with no problems at all! I don't run any power so this is an ideal setup for me. I really love the fast tuning. Its so nice to be able to jump around the bands and talk instantly. I highly recommend this tuner.
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| G0PGM |
Rating: |
2003-07-31 | |
| Unbelievable ! |
Time Owned: 0 to 3 months. |
| I have just acquired an Icom IC756 whilst on vaction in NC together with the AH-4 and was absolutely astounded at the performance I achieved with approximately 80 feet of insulated copper wire at 8 foot AGL draped over trees! First station worked under the relatively poor conditions that exist at this time was CY9A on St. Pauls Island where I received an honest 5/8: Also worked Monserrat, Netherlands and a G mobile. I am still finding the performance stunning as have used both yagi and quad beams and it compared extremely well compared to them. |
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| W9SWL |
Rating: |
2003-05-23 | |
| Super Tuners |
Time Owned: 3 to 6 months. |
I use the AH4 with a G5RV and IC-746. This combination gives me 160-6M at the push of a button. I also have an AH4 in the mobile with the IC-706MkIIG and an Outbacker PERTHplus. Super mobile.
Auto tuners are the only way to go. I have also had an Alinco EDX2. (Reviewed)The Icom tuners are faster, quiter, and have a better range (includes 6M).
I have not found any antenna(within reason and common sense) that I cannot tune. |
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| KN7K |
Rating: |
2003-05-17 | |
| Absolutely fantastic! |
Time Owned: 0 to 3 months. |
| I am in the process of downgrading my Ham station with the anticipation of going overseas in 2004. I recently purchased an ICOM 706 MKIIG and yesterday I installed the AH-4 using 100 feet of 22 guage wire. I live in an area with CC&R's and must keep a low profile. My AH-4 is mounted on a post just ouside my shack and very close to my ground rod. The random wire runs from the tuner and along the eve on one side of the house, and then to the top of a pole that is about 20 feet off the ground. From the pole it runs to the eve on the opposite side of the house. Prior to installing the tuner and the random wire, I was using an MFJ 1796 vertical antenna. The performance of the AH-4 with the random wire far exceeds the vertical and the AH-4 operates flawlessly with very low SWR from 80 through 6 meters. I only wish I would have purchased one earlier. I would recommend this tuner to anyone, especially those who live in areas with antenna restrictions. |
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| 9V1VV |
Rating: |
2003-05-04 | |
| Versatile |
Time Owned: 6 to 12 months. |
I use the AH-4 from a difficult antenna-restricted apartment. The antenna is a 60-foot horizontal long wire only 15 feet off the ground, no. 30 copper wire, almost invisible. I work worldwide on 80, 40 and 30 metres at night like this with the IC-718. SWR's are as good as 1.1:1 -then I take the AH-4 Maritime Mobile with the same transceiver. It is then fed by 100 feet of RG58 and 4-core control cable on the upper deck, into a simple 21-foot whip. Again excellent results on all bands (except 160, not surprising). The loss at 28 MHz using RG58 is probably 1,5 dB but I still get excellent reports. I have "ruggedisded" my AH-4 by removing the PCB and throwing away the case, and remounting the PCB inside a GRP case. Much stronger for Maritime use. Also use weatherproof PL259 and Coax connectors for simple plug-in of the two cables.
AH-4 : a great little device. |
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| N0DT |
Rating: |
2003-04-22 | |
| Good portable option |
Time Owned: 0 to 3 months. |
I purchased the AH-4 from a friend just before my recent trip to Micronesia. With a 58-foot piece of wire in an inverted-L configuration and eight 64-foot radials, I made QSO's worldwide operating for a few hours every night as V63JE. Had QSO's on every band 80-10m. This was during a time when the SFI was hovering around 100. I was impressed with the reliability and ruggedness of the AH-4. It held up well in Pohnpei when I operated in the middle of a tropical storm with rain being driven by 60mph wind gusts. When I accidently dropped the AH-4, it fell about ten feet and bounced off a big rock. No damage to the tuner. I never bothered using the plastic cap supplied with the AH-4 that is suppose to cover the ceramic insulator.
It packs well for portable use. With 60 feet of RG-8 and an identical length of control cable, the AH-4 did not even take up half of one suitcase. The set up time was minimal compared to a vertical or beam, where you have to assemble numerous pieces of antenna with the associated hardware. With the AH-4, just hang the wire, throw the radials on the ground and you're done. This was probably the main reason why I went with the AH-4. I was on vacation and didn't want to spend a lot of time assembling an antenna. It was also nice to be able to just QSY and hit the tune button. It tuned in under two seconds on all bands. While the components of the AH-4 aren't as efficient as a larger manual tuner, it still performed beyond my expectations and there was also no coaxial feedline loss that would have existed with a tuner at the radio. The radio I used on the trip was the IC-706MKIIG and it was as reliable as the AH-4.
This is just my one experience with it, but I would use it again in a similar situation (portable, quick setup & teardown). |
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| WE8Q |
Rating: |
2003-04-18 | |
| Great Mobile Tuner |
Time Owned: more than 12 months. |
| I use mine mounted on the bottom of my Chevy Truck with a 102" stainless steel CB whip antenna and an Icom IC-706MKIIG. It gets hit with water from the rear truck tire when it is raining and salt, sleet, slush, and snow in the winter. Never had any problems with it. Matches the whip on 75-6 meters in an instant, although the antenna is highly inefficient on 75 meters. I highly recommend this tuner for mobile ops. |
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| AB8PW |
Rating: |
2003-04-18 | |
| $300 wasted |
Time Owned: more than 12 months. |
I have owned this tuner for over a year now. 6 or 7 months ago I would have posted a positive review, but not now. When I put it up we had a dry summer, but then fall came and so did the rain. And as a result of the rain water got inside the tuner through the ceramic insulator at the top. I sent out an email to icom explaining what happened and I did not get a response. I am not happy with Icoms support department. Mine started to give me 2:1 and 3:1 matchs on certain bands, and it would not tune at all on other bands. That is when I knew something was up. I am working on fixing the water damage, but for a "waterproof" tuner, I should not have to.
It is a good concept, but will only provide adequete performance. I had mine originally hooked up to an earth ground and a 52 or 53 foot wire. Then it got "ghosts" in it. Something happens in the tuner and all of the sudden the tuner thinks it is trying to tune a wire that is already resonant on the band, and won't tune it (these tuners require a length of wire that is not resonant on any band to work.) The fix: Go trim off or add a foot to your wire length. I did that twice in the course of a month after it had been up for a month or two. I was willing to deal with that though, it was an easy fix and I was getting on HF, I wasn't busting pile up's with it, but it was getting me on HF, which kept me happy, until the water damage.
The Verdict, if you want to get antenna up quickly, like at field day or for a special event station, this is the way. If you are going to spend the time to do the calculations to find a peice of wire that is not resonant on any band, build a wire dipole and put an old fashioned tuner on it instead. |
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