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Reviews Categories | Antennas: HF: Verticals; Wire; Loop | ULTIMAX100 End Fed HF Antenna Help

Reviews Summary for ULTIMAX100 End Fed HF Antenna
ULTIMAX100 End Fed HF Antenna Reviews: 67 Average rating: 4.5/5 MSRP: $85.00
Description: SPECS:
Configuration - End Fed
Power - 1500 Watts PEP rating
Length - 24 feet
Weight - 3.5 pounds
Polarization – Vertical, Horizontal, Sloped
Connector – SO-239-50 ohm
SWR < 2.5:1 – (3:1 tuner required all radio tuners work)
Bands – from 3.0 MHz to 54 MHz (80 to 6 meters)
Radials - none required
Product is in production.
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KC7JNJ Rating: 5/5 Jan 26, 2018 10:40 Send this review to a friend
More update  Time owned: more than 12 months
More of an update: as of 15 Dec 2017-26Jan 2018 I have used nothing but a FT-817nd (with a BHI dsp, and a Sotabeems speech compressor) with this antenna. The solar flux has been between 69-71 the whole time. I have worked 33 states and 3 Japanese contacts. All on the stock 24ft of wire. I don’t understand it but I am on the air having a blast. And I am staying QRP!

I have this antenna on a 32ft jakite pole mounted as a vertical on top of my house. I have 40ft of counterpose wire running down to my wood fence and along it. I have tried many of the lengths of wire Albert suggested. But in the end I went back to 24ft. My location sucks for radio. I can never have a full sized windom or a nice tower and beam. But I am on the air and I am still having fun! I have worked 80-40-20-30-18-10 with it. It has been in the air a few winters and is still doing what I need. This not a full sized antenna mounted 100ft in the air between to trees miles from the nearest man made noise. You should not expect it work like one. What it does is keep me active, doing the parts of the hobby I like.
W6GAE Rating: 5/5 Dec 5, 2017 08:30 Send this review to a friend
Great Antenna!  Time owned: 0 to 3 months
As a new General licensee, I spent a good deal of time researching equipment for my entrance into the world of HF. After much consideration and a thorough review, I purchased a 33 foot Ultimax DXtreme given it's size, ease of use, frequency range and enthusiastic reviews (both of the antenna and of Albert). I was not let down. After some initial set up problems caused in total by my inexperience and with the very helpful guidance provided by Albert, I joined in a recent DX event contacting a number of operators around the country and, to my happiness, in Saipan and Brazil, all on my first night with a 100 watt transceiver! Have now contacted many across the US and even South Africa, Spain and Japan all with a 33 foot vertically mounted (on telescoping pole) antenna. Albert is a true professional whose focus is on delivering a superior product backed by a superior focus on customer service. He went the extra mile to get me up and running and provided quick and very helpful response to my questions. In a nutshell, great product with great customer support.
W1LTX Rating: 5/5 May 12, 2017 12:55 Send this review to a friend
great antenna   Time owned: 6 to 12 months
my ultimax 100 works great but i did improve the antenna by adding 44 ft 12 gage wire huge improvement
K6SDW Rating: 4/5 May 5, 2017 22:19 Send this review to a friend
end fed antennas  Time owned: more than 12 months
Like all end-fed antennas, there's nothing magical about them or should be.

This unit built fine and works when you understand it's limitations.

In my case for me to work 40/80 meters I had to increase length to around 67' otherwise this antennas was numb to the lower 2 bans.

This antenna never could resonate on 30meters with builtin antenna tuners

Cheers All.

WW2PT Rating: 5/5 Apr 2, 2017 22:13 Send this review to a friend
Good performance, great value  Time owned: more than 12 months
I purchased an Ultimax 100 antenna on a whim at the Orlando Hamcation in February 2016 to use for field portable QRP work and perhaps as an auxiliary antenna for my home station. The price was low enough for me to take a chance that it would live up to its specs (the hamfest special price was $55). If not, oh well... I spent more on gas and lunch that day, so the risk wasn't too terrible. I'm pleased to say it was money well spent.

Circumstances arose shortly afterwards that prevented me from operating until I moved into a new house; it wasn't until late January 2017 that I was finally able to get the radios set up again at a new QTH and give this new antenna a try. At my previous QTH I was using a ground-mounted Tarheel screwdriver vertical with a few 10' ground radials; at the present house I plan to eventually install a much better radial system and put the Tarheel back up, or perhaps go to a bigger vertical. Until then, however, the Ultimax is all I have to work with. The only other option at this time is to remain QRT.

At first I just had the antenna indoors, looped around my office/shack. I wasn't expecting much from an 24' wire inside a house with a metal roof - it was like operating inside a Faraday cage - and to be honest it was a challenge with the high noise and low signal levels, but over the next few weeks I was able to work 47 countries running between 50 and 100 watts with my Elecraft K3, and occasionally my KX2 at 5 watts. (Other than phone contests and a very occasional SSB contact, all of my operating is CW.)

At the beginning of March 2017 I moved the antenna outdoors, running the wire vertically up a 31' Jackite telescoping fiberglass mast that I zip-tied to the front deck railing just outside the window of my shack. Right away I noticed an improvement in signal strength, although the noise was still high. I was only running about 10' of coax despite Albert's recommended 25' minimum feedline length. But I was on the air, working DX, and happy. By the end of March I was up to 82 countries worked, including a few all-time new ones (Pitcairn Is., Côte d'Ivoire, Niger, Guinea-Bissau), plus a whole lot of other DX operations in February and March, giving me a bunch of new band slots. I've lately started working QRP most of the time, reducing the K3's output to 5 watts and only occasionally cranking it up to 100 watts if needed to get a new band slot. I've already got well over 20 countries worked QRP in just a couple of weeks with the Ultimax 100; if I can hear the DX, however weakly, I can work them almost all of the time. Hearing them was the problem, however, because my noise level was pretty high (a constant S6-S7 on pretty much all bands). The K3's noise reduction, blanker, and filtering helped a lot, but still... I knew I was missing a lot. I was also getting some RFI in the shack, most likely due to the short feedline and close proximity of the antenna to my equipment, forcing me to reduce power on certain bands.

Reading some of the reviews here, I found that others were able to reduce their noise levels and RFI by running longer feedlines, so today (April 2) I relocated the antenna to the back of the house with a 100' run of LMR-400 coax, and I'm happy to report that noise levels are greatly reduced (as low as S3 on 40m as I type this). Time will tell how much of an improvement in performance there will be, but at this moment it looks promising. I am now thinking about using a longer wire (66' seems to be the magic length, from what I've read here) to see if I can improve performance on 80m and 40m.

In all, I am very pleased with the Ultimax 100. The price is right, it has gotten me on the air quickly and easily while I gather parts for a more permanent antenna, and I plan to keep it in use even after my vertical is back in operation. Since I am a renter I need to keep a low profile, and this antenna and the Jackite pole supporting it are barely noticeable from the street. As I do not have a high-power ATU I've yet to try using my KPA500 amplifier with the Ultimax 100, so I cannot comment on its power handling claims. I can say that the ATUs in both my K3's and KX2 have no trouble matching this antenna on all bands from 80m through 6m.
N3HKN Rating: 5/5 Mar 7, 2017 15:41 Send this review to a friend
Solved By Vendor-UPDATE  Time owned: 0 to 3 months
Adding at least 31ft of coax to the feedline reduced the noise and improved the performance. The web site mentioned feedline for other models but the 100 had no mention of min-feedline. I just grabbed about 40ft of RG58 connected it to the match box. It is draped from the window on the third floor to the ground and back up to the tuner. I had to do that since the matchbox is only 6ft from the tuner. Reduced noise by 2 S-units. Dead bands were really not dead....
W1LWT Rating: 5/5 Feb 20, 2017 20:40 Send this review to a friend
great antenna  Time owned: more than 12 months
I bought 2 of these antenna's 5 years ago. one for the house as a back up.The second one is a portable i use with a 31'foot fibre pole. The both is great i have many contacts on either that makes this antenna my work horse with continued success.Never fails to not perform as it is advertised. comes very close to my other 21 antennas I have .Hanging in the air at my farm in Maine. Well worth every dollar you never be let down......
ONAIR Rating: 5/5 Dec 25, 2016 14:55 Send this review to a friend
Very Good Antenna!!!  Time owned: 0 to 3 months
Got one to take on the road when traveling. Was able to hit Europe from New England on 17 and 20 meters, and work most of the US on 10, 17 and 20! I have even made many contacts with it on 80 meters! All of this with 100 watts and the antenna strung up INDOORS, inside hotel rooms!! I can definitely recommend this antenna, especially if you like to travel or live in an antenna restricted community.
KE8BPC Rating: 1/5 Dec 13, 2016 14:50 Send this review to a friend
Recieve Only update  Time owned: 3 to 6 months
I had the balun opened up and this is what was found ", I opened up the balun. First, it is not a 9:1 unun transformer. It is wound like one.. but, only has 8 turns. Not sure what they were trying to accomplish there but it makes the wire length more critical. Second, they had not secured the toroid and it was loose and was against the side of the box against one of the contacts. Not sure how that would effect it but it might disturb the resonance saturation of the toroid " I hope this helps some one with the same issue.
KC3HJP Rating: 5/5 Sep 27, 2016 13:42 Send this review to a friend
Instant DX!  Time owned: 0 to 3 months
About 3 weeks after getting my Technician license I was hooked on amateur radio and wanted to get onto HF so I got my General but didn't have an HF antenna. With no antenna I needed to get busy. I had never been on HF before and was looking for something that only required a reasonable amount of space to install. After looking at many options the Utimax 100 seemed to be a good option after reading many reviews.

When I ordered the Utimax 100 I hadn't thought all of my installation options through and eventually realized while the antenna was in transit that I had an additional mounting option that would permit an antenna longer than 24'. I contacted Albert at Utimax and explained my situation and he said although it is shipped as a 24' antenna wire the matching network inside of the box could handle a 36', 44' or 66' wire. I went to my local electrical supply house and purchased 50' of 14 gauge wire. I cut the original wire off of the insulator and wrapped the new wire around it and crimped it with a similar style crimp just like it came from Utimax. I then measured 44' out from where the wire went through the insulator hole and cut the wire and soldered it onto a new yellow wire connector.

Our property is flat at the bottom for about 30' and then quickly slopes up a hill. I installed the antenna 9' off the ground in the lower yard on an existing 4x4 post with the wire sloping up at about a 30 degree angle and then its attached on top of the hill to a light pole also at about 9' off the ground. I used about 5' of parachute cord through the insulator and then through two pulleys with a 10lb weight holding the wire fairly tight. Mid-way between the bottom of the yard and the top of the yard I would have to say that the antenna wire is about 12-15' off the ground.

I also purchased a Utimax Line Isolator and that's connected to the antenna box with a 2' piece of coax. The line isolator has a 75' piece of coax getting the whole setup connected into the shack.

Once I got everything hooked up I went into the shack, turned on my IC-7100 and set it for 75 watts. I tuned it up on 20 meters and listened to a guy contesting in France. I pressed the PTT and gave out my call and I instantly got a reply! I wasn't sure what I needed to do next, I was shocked! A short time later I got into Croatia and then Ireland. It was all I could do to go back outside and seal up my coax connectors with some coax seal and electrical tape. I wanted to stay in the shack and play.

Since that time I've made many contacts both domestically and internationally. My furthest QSO so far has been to Uzice, Serbia which is 4783 miles from my QTH. I couldn't be happier with this antenna. I have a feeling that If I had an additional mounting option and could get the antenna wire even higher off of the ground it would probably do even better. I'm thinking about buying another one just to have around for field days and other portable use.

Oh by the way, lengthening the wire is only supposed to improve the reception and transmission abilities of the antenna and not widen the bands that it was originally designed for.
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