I have an old Cushcraft AR-270, 2m, 70cm antenna. It had been out in the weather and was not performing correctly so I took it apart to see if I could clean it up. I found the same type matching network in the Cushcraft. The cap and the coil were obviously different values. I repaired a broken solder joint at the top of the coil and cleaned it up. I put it all back together and it is performing very well. I don't completely understand how it works, but it does. Thanks for the video.

Looks like me. I love taking stuff apart to see what makes it tick. thanks Kevin.

Another excellent video, Kevin! In fairness, I don't think these are marketed to amateurs, but rather to the folks playing paintball and who are using Baofeng's for 'tactical comms'. Many of the chest harnesses made for paintballers have a pouch for a radio and also a loop that the antenna goes through, designed to mitigate the forces on the antenna base when trudging through the 'jungle'!

I have one of these I bought in 2020. The build quality on your antenna appears to be better than mine. On my antenna, the cap was barely glued on and came off in the summer heat. After an entire winter outside it was permanently folded over right above the base. It wasn't until I took it down that I noticed it was actually broken at the nut/bolt connection. Water had seeped in and it rusted through. After pulling off the single layer of heat shrink, I found two pieces of yellow tape measure steel tape.

I put a 48.8" version of this on a 20' last and it worked great on 2 meters!

👍 Thanks Kevin, that was interesting. I often wonder what's inside these HT or mobile whips. This was like antenna CSI 😂. The matching part with the connectors certainly looks useful for homebrew antennas. In fact, it would be useful if you could buy parts like that for HT/mobile whip experiments. In the past, I have made various mobile whips and portable antennas using cheap fibre glass "Roman blind" rods. I covered the rod with self-adjesive copper slug tape and then put heatshrink over the whole thing. Not as flexible as sprung steel but very RF conductive, lightweight and hardwearing. In terms of the matching in this design, it just looks like an auto-transformer with shorted turns as you say to tweak the inductance for the radiator plus the series capacitor to make the match to the transmitter a resistive impedance - kind of similar to that used in gamma match?

I have the same length Abbree, it wasn't anywhere as good the Nagoya. but I bought it for its fold over ability. even though I read reviews on Amazon saying that it was a Tape Measure blade inside, it didn't matter to me because hundreds of people make those 2 meter Tape Measure Yagi's all the time.

Thanks for the tear down!

Very cool. I really didn't want to do this to mine so ... THANKS!

Thanks for the "tear down", your assumptions were correct. Meanwhile, I've never understood why Baofeng couldn't make a decent HT antenna.

My primary HT antenna for hiking in the boonies. I think the Abbree brand works and many knock offs are of questionable quality.

Nicely presented

Thanks for the 2 videos, really interesting. It didn't work out for you but I'm sure it's given lots of people ideas on how to use tape measures in different types of antenna build. I'd like to find some time to build my own version. I wouldn't call it "tactical" though....probably call it "practical". 🤣

Another learning experience with/Professor Loughin. 👍🏻👋🇺🇸

Just stumbled across your channel today. Interesting video. I have heard mixed reviews, but mostly bad, on the Abbree brand of antennas.

I think they used a gas torch to burn off the tape measure paint.🔥🤔 Thanks for the autopsies, we were all very curious to see their construction. 👍🍻🤓

Thumbs up for the teardown

I saw one teardown on youtube and the antenna actually had printed tape measure inside! I have a couple of these Abbree antennas and they work much better than the original rubber ducks.

Thank you and that was interesting.

Thank you. I still love dismantling things. Near totally dismantled a large BW TV in high school. Thanks again. N0QFT

You need to try that really long one.. that thing is really powerful

These always seemed hit and miss. I have a few which work wonderfully and compare well against other antennas. But lots of people online and in videos seems to get poor performance.

Thanks for this video

lol i was expecting to see a real tape measure numbers and all. very cool. its actually better built than i thought it would be.

Wonderful, can you say "Big Clive". How about more of these type of videos?

I bought one, Thought it was pretty decent until I compared it to the stock rubber duck antenna that came with a baufeng. Honestly. The abbree could barely pick up NOAA without cutting in and out while the stock rubber duck seemed to be more consistent. Also, the abbree seems to work the same regardless of whether or not you have the flexible topper attached to the coil or not.

Great Teardown Kevin. now I can make one with a bit more confidence in being able to tune it. I'm so glad you produced a "Dremel" i thought you were gonna try with that flimsy plastic razor knife( which i see used a lot i n the US) do you have what we call in England a Stanley Knife, very rugged and just as sharp- but in my opinion a lot safer to use. Keep up the great work. PS. would love to hear your take on matching an end fed mono band half wave antenna. Barnie 73 de M7PBX.

If you look on Amazon at these antennas. They show what a authentic one looks like inside vs an imposter. The authentic one shows a base with about 25 wraps/coils. So either they have changed the design or this is an imposter?

Thanks for the dissection, very interesting. I would guess that's a standard inductor that the manufacturers solder-short for various applications. 73 de GØUSL

I was totally expecting to see various tape measures printed on the inside, like the factory in China was reusing waste from a nearby tape measure factory.

I have the 108cm version. On a quansheng UV-K5 for me it is the difference between being able to communicate on the local 2 meters repeater inside my ground floor apartment or not being able to open the repeater at all (with the standard rubber duck). I also bought and tried an Abbree 771 (clone)... It has a similar coil/capacitor construction in its base as you found inside. However that one doesn't perform that well on 2 meter, although NanoVNA measurements do show nice dips at 144 and 430 MHz.

Well done Kevin make a dipole out of tape metal strips then shrink wrap the metals ?

Thank you for the video! Maybe you could "re-tune" the coil, and get it tuned for the proper frequency. Then try the range test again? That would be an interesting project and video!

I got mine to work 74km on simplex at roughly more than 200 feet above sea level at 4 watts using my old trusty Icom IC 02AT. By the way, my Abbree is the 72cm version.

Thank you so much.

A few grest vids there Kevin. Not all are confident to dissect stuff they have purchased. At least you have highlighted the risks of alternates. 73

Still very new to ham but the first thought I had on coil was maybe it works like a jpole.

Nice break down. I agree for 6 or so bucks there is some good experimental hardware for later uses. Thanks for taking it apart. Vic de KE8JWE

i tested the longer one and am amazed. gave 2s units over the VX-8 original antenna, both receive and xmit

I have the 48" version. I ran an experiment with another ham 10 miles away on 2M simplex and it did work better that the spaghetti thin after market one I usually use. The problem is it is so long that it puts a heck of a strain on the HTs connector.

From Jeff Eide WA7LFP: Thanks again for an informative video. (As usual for you. : )

The simplest thing to do, would be just to solder a straight wire from the feed point, to where it connects to the threaded lug. So that essentially the base is nothing more than a feed through insulator. Cut the spring steel down to 18 in. And give the whole thing a good coating of epoxy line heat shrink. Could make an excellent quarter wave antenna. If you wanted to go the extra step solder a piece of silicone coated or meter test Pro wire to the negative side or ground side of the coil form. And heat shrink that as well, to provide a counter Poise or ground plane to the 19-in vertical.

Shorted turns on inductors are generally frowned upon, reason being that they add nothing but loss (circulating current).

The antenna seems to have good parts, I would experiment with the VNA to see if I can improove it's performance. The radiator is definitely resonant on 145M so you can't go wrong with it.

Excellent, everyone has wondered what’s in them 😂

At least the glue and heat shrink was good quality :)

Often wondered what was in them antennas.

2 length of what the make tape measures our of if you look into the top of the loading base it is pushed on and glued I wish they made one for 50 or 70 mhz

Modifying the transformer to proper 49:1 should make that a decent end fed half wave for 2m. Maybe removing the shorts and moving the tap would do the trick? I'd go that route. Actually thinking of making one from actual tape measure left from portable yagi projects.

Can u do more video about receiving image from satellite pls

Nice.............

thank u

I make it a firm rule to never by anything that starts with the word 'tactical'. It has served me well. Not that I would buy an antenna when I can build them for next to nothing and actually learn things. I'd guess the capacitor mostly bypasses the majority of the loading coil to operate on 440 MHz. Like most Chinese stuff it's a cheap kluge version of proper engineering design. BTW, once they have shorted a group of windings on the same side, if they need another half a turn removed they short it on the other side. I'm sure you're right. They use the same coil for all different lengths of antenna element, and they tune them on a test-fixture using blobs of solder because it's quicker than soldering on jumpers. I had a couple of those antennas come with a package deal on 2 cheap Baofeng radios and I found them to work not nearly as well as 1/4 wave pieces of stiff wire soldered into connector adapters I had in my junk box. I made 2 antennas, 1 for each band, (actually 3, if you count the one for the FM broadcast band.) They don't fold very well, but I can actually fold them in an emergency, then straighten them back out since they are just made from old copper house wire. The Broadcast band one I put a little loop in the end of and hang the whole thing on a nail on the wall, radio and all. It keeps the longer copper wire antenna vertical and keeps me from knocking over the radio.

I was also expecting to see actual tape measure inside. Those look a lot thicker or less flexible than a tape measure now that we can see it up close. I’m wondering if there’s still a use for those. Maybe as radials, or as part of a tape measure yagi?

I got an abbree to use on my ft60. It only lasted a month before the loading coil failed internally.

You could try copper plating the steel radiator as see how it effects performance. G7VFY

I was wondering if you would be interested in reviewing the TV antenna aspect?

Good job, Kevin. Is it possible that, in the original video, by walking in a straight line away from the dummy load, you might have been in a minor lobe of the antenna? Or, by doing a 360 degree walk around your signal source, the performance might have improved? Just a thought...

I have a Model 771-3 137-174/400-520 12W High Quality Tactical Antenna TwayRdio Made In China on my FT70D. Probably the same kind of setup. I havent compared it to the stock antenna yet. I live a mile from the repeater. Any advice on a better than stock antenna ?

Making a rough air core calculation for the inductance of the coil (0.05 μH?), an LC tank circuit resonance calculation would yield a resonant frequency of 205.5 MHz. Higher than the range test frequency of 146.46 MHz and Blue VNA sweep resonant frequency of 126.49 MHz shown in the other video. But perhaps my inductance calculation is off and the inductance of the coil is more like 0.13 μH which would yield a resonant frequency around 127 MHz.

Please, how long is wired in coil wound on 8mm diameter plastic form 18 gauge mag wire? Do somebody know that?

What would happen if someone took the base and added like a 771 or a rubber 🦆y on Thank u

Shorted turns is a good way to kill the inductor Q. So maybe that both "tunes" the transformer and broadens the bandwidth over the ranges the antenna claims to operate?

No continuity? Sounds liike the're using capacitance to match the load.

So basically it's a tactical tape measure! XD

Thought.... make the tape measure pieces into a dipole

The coil assembly looks like a useful junk box item. Maybe it might be worth desoldering the links one by one to see the effect on impedence/resonance. It seems to me that this is to enable multiple versions from a standard assembly. The reactance of the capacitor would make the element seem electrically shorter. In short, I am baffled. lol.

I'm wondering what would need to be fixed in order to make this work as expected?

Ok now I am pretty new to gmrs and foolishly bought two of the 42” tactical folding antennas. Well I guess my newbness got me and yes out of the box no bueno swr was like 6+. Shoot screwed again.🤨. But wait a month later from watching KZfaq and ham radio guys talk antenna tuning🤔. Guess what you can carefully remove the top cap with a dull knife or other tool. Then guess what you can cut them with a metal shears or tin snip.🤔…. A little math and calculations of the wavelength of the frequencies you wish to tx at. You can then trim and tune the antenna for your specific use case. It works try it. I trimmed mine for a full wave antenna for gmrs centered on 465.500Mhz. Come on ham guys you can do better. I am a newb. Back from the past of CB’s.

hello please make a video about how to tune(trim) a HF antenna without analyzer or VNA ???.

Interesting all the components of an actual useful antenna are present. Just their way of connecting them is a little strange. If you were to change the configuration so that the feed point was at approximately turn three or four., leaving the bottom of the coil connected to ground. And then unsorted the turns above the feed Point leading to the vertical. Then solder the capacitor from the turn where the feed point is connected. To the top of the coil where the antenna connect. And in a perfect world using a very small trim capacitor. You could adjust the capacitor for the best possible match. And you would have a base loaded 5/8 wave antenna. This is essentially a copy of the antenna that's used on a lot of the military manpac radios. The antenna used on the PRC 152 is slightly different as the base is nothing more than a spring. With interchangeable whips. There is a tuning unit built inside the handheld, that automatically adjusts the antenna for Optimum matching. But the basic design, at least of the whip section is similar to what was used on Manny Pac radios from the Korean War on. The base load assembly is very similar to what is in a 5/8 wave antenna. Just a very strange method of using a capacity to feed point. The capacitive feed point, protects the radio from a direct short, by providing an AC float path along the coil. Also because the antennas ground system will be constantly changing due to the size of the radio and how the user is holding it.

That seems like a typical design for a half wave end fed. I can’t imagine why it would work at 18 inches. Perhaps someone designed a longer antenna and someone else decided to shorten it without paying attention to theory

So what is the point of the coils and the capacitor? If I were to make an Abbree antenna, why couldn't I just go from the center wire to the tape?

Probably wont get an asnwer but worth a shot. Can you run the lower half that was covered in plastic with the coils without that protection? Can I just throw thick heatshrink over it and keep running it?

Very interesting , discovery !!!🧐👉🏻 There is a 11 meter one from the same company !! 🤔

Its made with Spring Steel

More importantly. What schematic software drawing tool did you use? It looks like it came from an ARRL book.

That plastic cover on the coil could have been removed by placing over a socket of proper demitions and screewing a bolt into the top side then a hammer or press could slide it off saving the coil , looks like a typical end fed antenna . I do Wonder if there using 3 quater waves for 70cm if so bet its not to good , be interesting to see

I’m still wondering what the capacitor is for.

As soon as you took off the shrink tubing and I saw two parallel radiators, I right away thought "V" antenna. Possible gain and directionality. Sometimes I think too much. Also. in other tests, I've seen the Abbree antenna slightly outperform quality aftermarket antennas. Every test is different and most likely every antenna is built a little different. In any case, not an antenna I'm much interested in using......yet I bought the long version......go figure.

So... is the whip suppose to be empty? and the ABBREE did not advertise that as showed. there was suppose to be maybe 25 turns with copper wire.... is this a gimmick?

Desolder, reorient jumpers, cap and test. Would be good to se you make it right and perform as it should. Just saying

An 18" radiator? They should have skipped the matching network!

👌👍

Same thing many Military portables use.

I added a 19" rat tail to the ground on my handie and it works really well with the 42" Abbree, might want to try that... before you throw it away. Keep the spring steel for making a UHF yagi, they are better than the usual tape measure steel!

I bet if you replaced the spring steel with same-sized strips of copper, you’d find the performance would greatly improve. Skin effect pushes rf current to the surface of any conductor. That blued steel adds new meaning to “rubber dummy load”. de kg5ar

that moment you realize your antenna is made of tape measure scraps.

Spring steel.

Why’s your work bench look burnt in random letters and numbers like mine for? I’d really like know how that happens

FYI: Speaking of Abbree . The Abbree AR-869 was tested by FEPLabs Radio and it FAILED badly for spurious emissions for 2 meters. "Hero or ZERO?? Signal Check 1/8"

Hmmm. I wonder if there's a difference between this antenna and the Abbree _tri-band_ 18.89-incher? Something may be wrong with your components because these antennas actually test very well, not only against the stock antennas, but against the Nagoya NA-771 and 24J. The tri-band model looks _identical_ to the dual band model. Side by side there's no difference whatsoever. I suspect the Abbree dual-band AR-771 is the same as the tri-band AR-771 (the model numbers are the same). And I suspect the dual-band and tri-band flat-tacts are identical, the only differences, of course, being the price. To be on the safe side, I label them as I don't want to rip them asunder to test my theory. What do _you_ think?

hey man, how is life? Are you better?

What do you think a normal round antenna is...yep a round piece of metal. Surprise!

is it a real ABBREE

Its an old video' but what ty he hay. No one seems to understand how these are supposed to be used. This is not a super amazing antenna. Really its no better than the basic 6" ones. How it is used. You are in a trench or fox hole and shells are dropping all around you. Which do you want to do. Stick you whole radio and had out into the shrapnel filled air inorder to receive transmissions. Or.... deploy the extra length of the tactical wip and not have your hand blown off. 42" model is great for bunker. Small hole in roof. Slide it up so as to receive form within cover. Plus extra length means if it is hit, just tape it up and keep using it. Down side you still have to expose yourself to transmit.

Hey Kevin: 1) Thanks for the tear-down, I was wondering what was in there. 2) I was reading some of the comments where some of the guys were saying about using the radiator elements as an "Inverted Vee", I don't see how they could be as the tape measure elements are at the same potential considering they're bolted to the same feed point, the only thing I see is the two tape measure parts are in parallel and thusly reducing the radiation resistance of the radiating elements by 1/2. 3) I DO NOT understand the print of that coil base AT ALL, shouldn't the coil be in line with the center conductor of the feed point and NOT the ground for loading???? Unless they're using the coil as a counterpoise for the actual radiating elements???? Comments would be GRATEFULLY appreciated! Thanks again for ALL your work in bringing us these EXTREMELY interesting and thought provoking vids!! L8R Bro.

This is the absolute best ABBREE video yet! Finally, someone shows us exactly what it is. DE WA1KLI

Most likely a Slim-Jim antenna.

We all know HT antenna is affected by other things. So hard to isolate variables.