โŒ

Normal view

There are new articles available, click to refresh the page.
Before yesterdayMain stream

Maximize Your Signal with the Chameleon URT-1 Remote Antenna Tuner

By: kb9vbr
2 July 2024 at 21:09

The Chameleon URT-1 is a remote outdoor antenna tuner for almost any type of antenna or model of transceiver. This wide range tuner matches resonant and non-resonant wires, verticals, and long wire antennas with its range of 5 to 1500 ohms of impedance. The URT-1 has a 50 ohm coaxial port and a wire beehive connector for added versatility. And the unit is weather proof so it can be mounted outdoors near the feed point of the antenna.

Chameleon CHA URT-1 https://chameleonantenna.com/shop-here/ols/products/cha-urt-1

What are remote tuners

The purpose of an antenna tuner is not to โ€˜tuneโ€™ your antenna, but instead to provide a proper impedance match to your transceiver. Modern transceivers require a 50 ohm impedance and if there is a mismatch, the transceiver will respond, at the very least, by reducing output power, and at the worst, damaging the final amplifier components. So in order to deliver all available power to your antenna, a proper impedance match is required. This is a simplistic explanation, but sufficient for today.

Screenshot

Usually the tuner, either manual or automatic is placed near the transceiver. This is fine in most cases. If your feed line run is short, it wonโ€™t make a difference. But coaxial cable does introduce losses into the antenna system and if your antenna has a high impedance at the feed point, the mismatch will create standing waves, and the elevated SWR can be characterized as power lost in the feed line. Again thatโ€™s a simplistic explanation.

So how do we increase the overall efficiency of our antenna system? One method is to move the antenna tuner from the transceiver over to the antenna feedpoint. Situating the tuner at the antenna allows it to deliver the proper impedance match, which will be 50 ohms, to the feed line. Since impedance is matched at the coax, we can run longer pieces of cable without fear of losing energy due to high SWR on the cable.

Now remote tuners are typically used with non resonant antennas, either long wires or verticals. A resonant antenna, like a dipole or end fed half wave should have close to a 50 ohm impedance at the feed point. The tuner located at your transceiver will be used to fix slight mismatches or to extend the bandwidth of your antenna. Remote tuners would be overkill in these situations.

But with, say a 43 foot vertical antenna, the impedance may be between 400 โ€“ 900 Ohms. A 9:1 transformer could help knock that down, but using a remote tuner instead, will take whatever impedance the antenna is and deliver a consistent 50 ohms to the feed line, reducing overall system losses.

URT-1 Specifications

The URT-1 covers 1.8 to 54 Mhz and has 16,000 memories for quick recall when tuning. It can match any antenna with an impedance of 5 to 1,500 Ohms. Thatโ€™s like a 30:1 match. And it can handle up to 125 watts sideband or CW and 60 watts on the digital modes.

Screenshot

Opening up the box, things may look a little familiar. This tuner is custom manufactured by Mat Tuner for Chameleon. It does look very similar to their MAT 40 remote tuner, but there are some key differences.

The tuner comes in two parts, the first is the coupler box. This connects to the transceiver and to a 12 volt power source. Then your coax cable runs all the way out to the tuner box which sits at the antenna feed point. You will notice that there are not separate control cables for the tuner. Power and tuner control are fed through the coax cable by way of a Bias-T circuit. The benefit to that is that you donโ€™t have to run a second cable to the tuner unit, but the downside is that you need to initiate tunes by pressing the tuning button on the coupler.

The tuner unit is constructed out a aluminum alloy and it weather proof. On the top of the unit is a beehive connector for feeding wire or vertical antennas. On the bottom is a counter poise and ground connector along with two UHF female connectors. One UHF connector connects to your coax run coming from the coupler and the second is for feeding antennas that have a similar SO-239 connection point.

The tuner comes with a set of rails so that you can mount it to a post or board using a pair of U-Bolts. An option 12 volt AC adapter is also available.
So whatโ€™s different between the URT-1 and the MAT 40 tuner? Namely the addition of a 50 ohm coaxial output port and the removal of the brand specific control cables. The URT-1 is a bit more universal in that the coupler unit will work with just about any brand or model of transceiver.

How to use Use the URT-1

Using the URT-1 is pretty simple. Weโ€™ll first connect the coupler to our transceiver. My main antenna, a G5RV, is connected to my LDG auto tuner, so going to put this one onto the 2nd antenna port on my transceiver. A coax jumper goes from the radio to the coupler. The antenna coax is then connected to the other port on the coupler. Finally connect the power. The green power light should glow. If you see the red error light, that means the there is a short circuit somewhere in the coax connection between the coupler and the tuner.

When connecting the tuner, you can not have any devices like switches, diplexers, or meters in the path between the coupler and the tuner. These could cause a short circuit, potentially damaging the tuner or your device.

To initiate a tune, put your transceiver into a constant carrier mode like RTTY. Set the power level to 15 watts or less, briefly hit the tune button, and immediately key the transmitter. Watch the transceiver SWR meter and it will show the resulting SWR when the tuning cycle is complete. Unkey the transmitter. A complete tuning cycle will take five seconds or less.

At this point you can transmit normally. When changing bands, you will reinitiate the tune process. The tuner has 16,000 memories, so once the unit finds a good match, it will remember it for faster subsequent tunes.

Now letโ€™s head outdoors and Iโ€™ll show you a couple of ways you can use the remote tuner in your portable amateur radio operations.

My experiences

What are my thoughts on the Chameleon URT-1 remote antenna tuner? First off, I must say that this unit is well constructed. The tuning unit consists of an aluminum alloy body that has a certain amount of heft to it. It wins points on that item alone. Taking this out into the field was a breeze as I didnโ€™t have to run a separate control cable to the tuner for power. Operationally, it tunes fast and had no problem finding a match that was 1.5:1 or less. I think the only time I had issues with it getting a good match was with my 25 foot Franken-tenna on the 15 meter band. In that instance it gave up at about 1.8:1. But with the Frankentenna it did perform quite well on 10, 15, 20, and 40 meters despite the bands not being in the best condition. I made 210 contacts on those bands activating the Mountain Bay state trail, with the bulk of them on the 20 meter band.

Screenshot

With the end fed random wire antenna, I connected the tuner up to UHF connection on the antenna. The addition of the 9:1 transformer with the tuner made for super fast tune times. Every time it found a match at rocket speed. For that activation of Ackley Wildlife Area I ended up with 176 contacts on 10, 12, 15, 17, and 20 meters. The great thing about non resonant antennas is their agility. To switch bands, all I had to do was hit the tune button and I was good to go.

I had the same experience back here at home with the 71 foot non resonant wire. Once it learned the antenna, it would re-tune almost instantly. I was able to get matches with this wire from 10 meters all the way down to 80 meters. Operationally, the antenna performed just as well, maybe a bit better than with my other tuner located at the feed point. This antenna is being fed with 75 feet of RG-8X, so the better match at the feed point does make a difference.

As for things I donโ€™t quite like about the tuner, First off these UHF ports are not labeled, so you need to look at the instructions to determine which goes to the coupler and which goes to the antenna. Also the ports didnโ€™t come with covers. If you are using the bee hive connector, having a cover on the unused UHF port would be nice. Iโ€™ve got a friend that 3D printed some, so i did have something that worked. Finally, and probably the biggest, is that you have to press the tune button on the coupler to initiate a tune. If your SWR changes or you change bands, the tuner wonโ€™t automatically retune, it needs to be activated. That involves switching to a carrier mode like RTTTY, pressing the tune button, and then transmitting a carrier. Not the worst thing in the world, but also not fully automatic like some brands of remote tuners. But those require a separate control and power cable and up side of this tuner is that you donโ€™t have to run a separate power and control cable to the tuner. Your power runs through the coax, which makes installation a breeze.

But, final words, Iโ€™ve been looking for a remote tuner at the hamfests. Everything Iโ€™ve seen is overpriced or in bad shape. Itโ€™s a bit serendipitous for Chameleon to be sending me this as it opens up the door to a bunch of different antenna configurations that Iโ€™ll be able to demonstrate. Iโ€™ve got some great ideas to use this tuner with, so youโ€™ll want to stick around for that.

Build a random wire antenna and make amazing contacts: https://youtu.be/D_-aNzrIXWs

Yaesu FT-891 transceiver: https://amzn.to/3RSg4DO
213 inch whip antenna: https://amzn.to/3O3Bvkm
Feather Flag Base: https://amzn.to/3O6O7al
Antenna mirror mount jaw clamp: https://amzn.to/48yzRPL
3/8ร—24 SO-239 stud mount: https://amzn.to/3Sjre69

As a bonus, patrons can view the full, unedited phone contacts for this Parks on the Air activation. Visit my page on Patreon for details: https://www.patreon.com/kb9vbrantennas

I do return QSL, if you made a contact with me and would like a QSL, please send me one. Return postage not necessary, but always appreciated. As they say, KB9VBR is โ€˜good in the book.


Links may be affiliate links. As an Amazon Associate, I earn from qualifying purchases. This does not affect the price you pay.


The post Maximize Your Signal with the Chameleon URT-1 Remote Antenna Tuner appeared first on KB9VBR Antennas.

Building the CaHRTenna Poseidon: A non-resonant vertical antenna powerhouse

By: kb9vbr
19 June 2024 at 12:12

CaHRTenna Poseidon is the Coffee and Ham Radioโ€™s take on the popular Rybakov vertical non resonant antenna. Today weโ€™ll talk about Poseidon, show you how to build your own, and put the Greek god of the sea on the air.

CaHRTenna Poseidon Vertical Antenna: https://coffee-and-ham-radios.square.site/product/cahrtenna-poseidon-vertical-antenna

The Rybakov Antenna: https://ve3gam.webqth.com/am-work/rybakov/rybakov.html

Coffee and Ham Radioโ€™s Poseidon is based on an antenna called the Rybakov. That antenna, created by Italian ham IV3SBE about 20 years ago is a non resonant ground ground mounted vertical antenna with a radiating element of 25 feet. At the feed point is a 4:1 unun or transformer to match the 200 ohm impedance the antenna presents. Radials of about a similar length provide the ground network for the antenna. With a tuner, the antenna will operate on the 80 through 6 meter bands, although it gets pretty inefficient on 40 meters and below. Your best performance will be on the higher bands and this style of antenna really excels on 10, 12, and 15 meters. As you get higher in frequency, the RF radiation angle gets lower and lower, making it an excellent DX antenna.

But why the name Rybakov? When IV3SBE designed the antenna, he envisioned it being supported by an 8 meter fishing pole. The antennaโ€™s 25 foot length makes it perfect to deploy with a lightweight mast or fishing pole. Rybakov is Russian for fisherman, so it makes sense to give the fishing pole antenna that name.

Coffee and Ham Radios did send me a Poseidon vertical antenna kit to build and put on the air in exchange for a video. But my opinions are my own and there is no outside influence. So letโ€™s head inside, build this antenna, and then put it on the air.

Screenshot

So what makes Poseidon different? I believe the key difference lies in the transformer. If you look at most 4:1 unun designs, they use a red T200 style toroid. The red toroids work well and offer very good overall efficiency, but a key design element of this antenna was to make is tunable with a transceiverโ€™s internal tuner. That means you will need an SWR thatโ€™s 3:1 or less over the entire frequency range the antenna is designed for. Unfortunately the T200 isnโ€™t up to that and you will get higher impedances at the lower frequencies. This green colored iron powder core thatโ€™s used in Poseidon offers an overall better impedance matching at a wider range of frequencies, with a slight tradeoff of efficiency. Is the tradeoff worth it? It is if you donโ€™t want to bring an extra piece of gear out into the field. Also consider, lower impedance coming out of the antenna means less losses in your feed line. So overall, its a valid choice to make.

The second consideration with this antenna is that 4:1 transformers can pass along common mode currents, causing the outer shield of your feed line to radiate. This will affect your antennaโ€™s radiation pattern. Proper 4:1 windings will also include a second toroid would as a 1:1 choke. In order to make this antenna easier to build, Poseidon does not use the double toroid winding, instead you will need a choke of some sort on your coaxial cable. Today Iโ€™ll be using an integrated choke on my feed line for this antenna.

Screenshot

Graphical contact map provided by: https://www.qsomap.com/
Thank you for your support.

How I record my contact audio: https://youtu.be/tOqzZPphE7k
My headset trigger switch: https://youtu.be/b5Wu8BlrSF0
Heil Ham Radio BM-17 Dual headset: https://heilhamradio.com/product/bm-17-2/


Links may be affiliate links. As an Amazon Associate, I earn from qualifying purchases. This does not affect the price you pay.


Like what you see? You can leave me a tip:
https://www.paypal.me/kb9vbr

Become a patron! Unlock exclusive content at: https://www.patreon.com/kb9vbrantennas

Support Ham Radio Q&A by shopping at Amazon: http://amzn.to/2kO6LH7

The post Building the CaHRTenna Poseidon: A non-resonant vertical antenna powerhouse appeared first on KB9VBR Antennas.

Antenna Book Face-Off: Rothammel vs ARRL โ€“ Which one reigns supreme?

By: kb9vbr
29 May 2024 at 12:20

I take a look at the 13th revised edition and first English translation of Rothammelโ€™s Antenna book and compare is to the new 25th Edition of the ARRL Antenna Book. Which book stands out as the best?

Rothammels Antenna Book: https://rothammel.com/Rothammels-Antenna-Book
ARRL Antenna Book 25th Edition: https://amzn.to/3T2OQv4

Recently on the livestream we had a discussion about antenna books, specifically the Rothammel Antenna Book. This substantial tome is frequently called the antenna bible, for its comprehensive scope. Up until recently the book was only available in German, but now an english translation of the 13th edition is available. That translation opens this guide up to a whole new audience and many hams are discovering what a valuable resource it is. Weโ€™ll look inside the book in a bit, but first the specs,

Rothammels antenna book is 1600 pages, dimensions are , and it weighs about 4 pounds. The paper has a textured finish and the text is set in 10 point type. This smaller typeface can make it a bit harder to read, so get your reading glasses tuned up for it. Cost of the book is 59 euros. I ordered it online direct from the DARC, the German amateur radio association and with exchange and international shipping, my cost was $87 US dollars.

Weโ€™re going to compare that book to the American standard antenna guide, the ARRL Antenna book. The ARRL antenna book has been around since 1939 and the new 25th edition has some pretty substantial updates in it. The latest edition was released in the fall of 2023, so this is the newest guide available. This book is no slouch either, it weighs five pounds, is inches and and has 1120 pages. While the Rothammel guides paper has a duller texture, the ARRL antenna book is a smooth coated paper set in an easier to read 12 point type. The paperback edition is $69.95 and is available direct from the ARRL or from online retailers.

For full disclosure, both books were purchased by me with my own funds.

In perusing the books, youโ€™ll spot some key differences right away, so lets open them up, take a look at the contents and talk about the information inside.

So which book is right for you. Rothammels is certainly more comprehensive with its quantity of antenna styles and variations. The content is direct and too the point. While it may not be comprehensive, it does give you the references and links so you can go off and explore.

On the other hand, the ARRL guide may not catalog such a diversity of antenna styles, the information it has is a bit deeper and well rounded. The ARRL antenna book also offers a substantial amount of electronic content to supplement the printed version and has plans and diagrams for antenna projects you can build.

One thing Iโ€™ve noticed between these two books is that the ARRL guide is more of a snapshot of what is the current trend in amateur operation. If youโ€™ve followed past editions of this book, youโ€™ll see content added and content taken away. If a design or style of antenna falls out of popular favor, it may be eliminated or have a diminished presence in the book. Thatโ€™s one of the reasons why past editions of the antenna guide are still quite popular.

On the other hand, it feels like once an antenna makes its way into Rothammels, its pretty much there to stay. Youโ€™ll find information on antennas both old and new and there are some pretty esoteric styles that are covered in the book. Not having any experience with previous editions, as they are all printed in german, thatโ€™s my feeling in reading this revised 13th edition. From a research standpoint, this extreme depth is great as you can look up an antenna, search the citations and reference material, and go on from there.

Which may be the biggest comparison between these two books. Rothammels is a starting point, a guide to get you going on a project or antenna design, while the ARRL antenna guide is the one stop shop with theory, design, and plans.

If you are starting out on the journey to build your own antenna systems and want to know more about the theory and design, Iโ€™d add the ARRL antenna book to your library.

If you are looking for ready reference, maybe not so much a construction book, then Iโ€™d go with Rothammel. Although you can certainly build much of anything thats in the Rothammels guide. It just takes more work to put the formulas, charts, and sketches together into a working antenna. Iโ€™ve found Rothammels to be valuable in looking something up, getting a concise overview and working from there.
Final word, I think both are excellent books and both are valuable in their own regard. I own previous editions of the ARRL antenna guide and was glad when they finally came out with a new edition this last year. And Iโ€™m also glad that an english translation is available for this seminal geman antenna book. Iโ€™ll be using both in future antenna projects.


Links may be affiliate links. As an Amazon Associate, I earn from qualifying purchases. This does not affect the price you pay.


Timestamp
00:00:00 Introduction
00:00:23 Rothammels Antenna Book 13th revised edition English
00:01:42 ARRL Antenna Book 25th Edition
00:03:07 Look ARRL Antenna Book 25th Edition
00: 10:40 Whatโ€™s inside the Rothammels Antenna Book
00:17:51 Which is the best antenna book

Like what you see? You can leave me a tip:
https://www.paypal.me/kb9vbr

Become a patron! Unlock exclusive content at: https://www.patreon.com/kb9vbrantennas

Support Ham Radio Q&A by shopping at Amazon: http://amzn.to/2kO6LH7

The post Antenna Book Face-Off: Rothammel vs ARRL โ€“ Which one reigns supreme? appeared first on KB9VBR Antennas.

Portable Ham Radio: Chameleon CHA Stinger Kit Review

By: kb9vbr
23 May 2024 at 12:47

The Chameleon CHA Stinger Kit is a versatile solution for a vertical antenna counterpoise or ground plane. The Stinger kit consists of six 48 inch stainless steel elements with all weather banana plugs on one end and a teardrop on the other. The Stingers are a quick deployment option for times in which you may not have the space to put out a conventional radial network, like if you are operating on a patio or deck, or other high traffic areas.

Chameleon CHA Stinger Kit:
https://chameleonantenna.com/shop-here/ols/products/cha-stinger-kit-d/v/CHA-STINGER-KIT-KIT

Chameleon antennas recently introduced the Stinger kit. This is billed as a versatile solution for a vertical antenna counterpoise or ground plane The Stinger kit consists of six 48 inch stainless steel elements with all weather banana plugs on one end and a teardrop on the other.

For antennas, like the Chameleon PRV system, you insert the 2 mm banana plugs into the holes of the radial puck that comes with the antenna. For other antennas, like the MPAS 2, an optional 6 port puck is available to convert the antenna counterpoise to the Stinger kit. Stinger kits can be ordered either with or without the puck, depending on if you need that part or not.

The Stingers are a quick deployment option for times in which you may not have the space to put out a conventional radial network, like if you are operating on a patio or deck, or other limited areas.

Performance of the stinger kit is good. Using the 58 inch whip on the Chameleon PRV antenna, I was about to get the SWR down to around 1.5:1 on the 20, 15, and 10 meter bands. Chameleon states that a tuner may be necessary for 40 meter operation in this radial configuration. On air reports were good on those bands.

Similar results were achieved with the MPAS 2 non resonant vertical antenna.

Not stretching out radials, like in limited spaces and high traffic areas may be a benefit to some portable operators, and the Chameleon Stinger Kit offers that convenience and versatility in those situations.

The Chameleon Stinger kit can be found online at chameleonantenna.com. Thank you to Chameleon for sending me a stinger kit for this review. Links to their online store are in the video description.


Links may be affiliate links. As an Amazon Associate, I earn from qualifying purchases. This does not affect the price you pay.


Like what you see? You can leave me a tip:
https://www.paypal.me/kb9vbr

Become a patron! Unlock exclusive content at: https://www.patreon.com/kb9vbrantennas

Support Ham Radio Q&A by shopping at Amazon: http://amzn.to/2kO6LH7

The post Portable Ham Radio: Chameleon CHA Stinger Kit Review appeared first on KB9VBR Antennas.

Discover the Power of Magnetic Loop Antennas: Chameleon F-Loop 3.0

By: kb9vbr
29 April 2024 at 11:58

In the proper sense, small magnetic loop antennas are not considered a compromise. With a properly sized loop, they have the efficiency of a properly mounted half wave dipole*. The Chameleon F-Loop 3.0 antenna unleashes that power with a magnetic loop design that is easy to deploy and offers a broad range of frequency support between 10 and 80 meters on the HF bands.

Chameleon CHA F-Loop 3.0 Magnetic Loop Antenna: https://chameleonantenna.com/shop-here/ols/products/cha-f-loop-30

Konsait Black Camera 323 Quick Release Plate with Special Adapter (200PL-14) for use with Manfrotto tripods: https://amzn.to/49fTAEo

(*) An Overview of the Underestimated Magnetic Loop HF Antenna
Leigh Turner, VK5KLT, 2015 (accessed February 12, 2024)
https://www.nonstopsystems.com/radio/pdf-ant/article-antenna-mag-loop-2.pdf

Magnetic loop antennas consist of three components. The first, and most noticeable is a large primary loop. This loop circumference is typically within โ…“ to โ…› the operating frequency range of the antenna. Inside this primary loop is a smaller conducting loop. RF energy is fed into the conducting loop and the electromagnetic coupling between the two are what creates the RF radiation. The third part is a tuning capacitor, which is connected to the large primary loop. Loop antennas have a low radiation resistance and the purpose of the capacitor is to eliminate reactance so that the loop becomes a resonant radiator. Since it is a resonant antenna, no antenna tuner or transmatch is required.

Since magnetic loop antennas have a low radiation resistance, high currents flow through the primary loop. These current flows are what radiates the RF energy in the form of electromagnetic coupling. These current flows are a limiting factor of magnetic loop antennas as if you give them too much transmit power, the capacitor will arc and short circuit.

With that said, magnetic loop antennas are a great choice for QRP or lower power operating and weโ€™ll talk about those benefits and features in a bit, but first, letโ€™s look at the Chameleon F-Loop kit.

Tuning a magnetic loop antenna

Now we get to the fun part, tuning your F-Loop antenna. Magnetic loop antennas have a very high Q, or quality factor. What that means is that their 2:1 bandwidth is very sharp and pronounced. As you go lower in frequency, the bandwidth shrinks. This loop will have 210 KHz of bandwidth on the 10 meter band, but on 80 meters, that bandwidth drops to 6 KHz. This is due to the function and size of the radiating loop. To a certain degree, a larger loop will give you more bandwidth on the lower frequencies, but even at that there are limits. Basically if you want to change frequencies, you will have to readjust the antenna.

There are two methods of adjusting the loop. The first is to use an antenna analyzer. Connect the analyzer and turn the tuning knob until you see a dip on the meter. As you are tuning, you will notice that touching the unit will slightly detune it, so as you are tuning, you will need to step away from the unit to get a more accurate reading. The knob is very sensitive and the 6:1 reduction drive lets you do precise adjustments. When you get in the ballpark, it will take very slight movements of the knob to hit the sweet spot.

The second method to tune the loop is to listen to your transceiver. As your turn the knob, you will hear the noise level increase and then decrease. This point of maximum noise is the sweet spot of the antenna and the result of your tuned frequency. After adjusting for maximum noise, make a test transmission to check the SWR and make any minor adjustments until you are at the minimum. You may not always hit 1:1 match, but anything under 2:1 SWR is fine and the antenna will operate well.

With magnetic loop antennas, you should never use a tuner or transmatch. These antennas are designed to work without a tuner and should only be adjusted to their resonant frequency using the tuning knob.

Once the antenna is adjusted, go ahead and transmit. If you need to change frequency, you will need to readjust the antenna.

My experiences with magnetic loop antennas

So what are my experiences with the F-Loop magnetic loop antenna? Generally, I had a lot of fun with this antenna. It sets up and tears down quickly, it is reasonably efficient, and by virtue of its use of the H or magnetic fields, it is highly resistant to man made noise. That makes these antennas great choices if you are in an urban environment or a residential area that is prone to RF interference.

I took this antenna out for a few Parks on the air activations to test its performance. This antenna paired really well with my Yaesu FT-817 QRP transceiver, but I would think this is an excellent companion also to the Icom IC-805, Elecraft KX series or the Xiegu G90 or 6100 low power rigs.

Magnetic loop antennas are often characterized as QRP antennas and the F-Loop can handle up to 25 watts sideband and 10 watts CW or digital. If you use more power than that, the air capacitor inside the tuning unit will start to arc. And therein lies the misconception that magnetic loop antennas are poor performing antennas.

In reality, they are not. A magnetic loop will work just as well as other antennas. At their best, a magnetic loop on the upper bands is comparable in performance to a dipole. At their worst, they are 6 dB or 1 S unit lower than an optimized three element beam. Which brings me to my on air test.

Looking at the data, the magnetic loop performed quite favorably when compared to my customary ยผ wave vertical antenna. On FT8, the signal reports where pretty equivalent. Using my Yaesu FT-817 set to 5 watts, I ran both antennas on the 20 meter band for about 45 minutes each and in that time period received about 18 contacts on each antenna. With the magnetic loop I gave an average signal report of -9 and received a report of -11 dB. With the vertical, I gave a signal report of -13 and received a -12 dB. To me, that isnโ€™t much of a difference. In fact, the only difference that I can spot is that in looking at the maps of contacts, the distances achieved with the vertical were further than the magnetic loop. But that could be attributed to the vertical antenna propensity for having a lower RF angle of radiation.

So what are the down sides of Chameleon F-Loop antenna. I donโ€™t think there is really anything negative about this antenna on it own, this is a highly engineered and well constructed piece of equipment. But the negatives relate to magnetic loop antennas in general. First is its low power capability. I know a lot of people arenโ€™t into QRP operation so the 25 watt limit on sideband may be a turnoff. Chameleon does offer an optional power compensator that allows you to use up to 60 watts sideband with the loop, but still these are categorized as low power antennas.

The second downside is the relatively narrow bandwidth. If you change frequencies, you will need to re tune the antenna. You certainly have more bandwidth on 10 and 15 meters, but 20 meters and lower, the bandwidth approaches paper thin ranges. That can be great for rejecting adjacent noise and signals, but if you are the hunt and pounce type of person, you will find the bandwidth highly limiting.

I think these two limitations of magnetic loops really lend themselves to digital and CW operation. The weak signal modes like FT8 and the narrow bandwidth of CW really make these antennas shine. And being that we are at the peak of the solar cycle, we can also take advantage of their enhanced performance on the higher HF bands.

Since magnetic loop antennas also exploit the H or magnetic field, they can be successfully used indoors with a minimal performance loss. H fields have better penetration through walls and glass, so If you live in an apartment, condo, or have HOA limits, this may be the type of antenna that gets you on the air at home. In a high RF noise environment, their enhanced signal to noise ratio will also be of a benefit, and you may be able to hear things that you miss with other antennas.


Links may be affiliate links. As an Amazon Associate, I earn from qualifying purchases. This does not affect the price you pay.


Like what you see? You can leave me a tip:
https://www.paypal.me/kb9vbr

Become a patron! Unlock exclusive content at: https://www.patreon.com/kb9vbrantennas

Support Ham Radio Q&A by shopping at Amazon: http://amzn.to/2kO6LH7

Timestamp
00:00:00 Introduction
00:00:30 Chameleon F-Loop 3.0 Magnetic Loop Antenna
00:01:02 How do magnetic loop antenna works
00:02:26 Chameleon F-Loop 3.0 Kit Options
00:04:38 Assembling the Magnetic Loop Antenna
00:07:04 Tuning your Magnetic Loop Antenna
00:08:59 Chameleon F-Loop 3 80 meter band
00:09:51 Personal Experience with the F-Loop
00:14:15 Magnetic Loops are NOT compromise antennas
00:16:35 Who are magnetic loop antennas good for

The post Discover the Power of Magnetic Loop Antennas: Chameleon F-Loop 3.0 appeared first on KB9VBR Antennas.

Everything you wanted to know about Chameleonโ€™s PRV Vertical Antenna Kit

By: kb9vbr
26 March 2024 at 12:17

I made over 1000 contacts and spent a month working with the Chameleon PRV or Portable Resonant Vertical Antenna kit. The core of the PRV is the Multi Configuration Coil or MCC. This adjustable coil, when paired with an appropriate length whip, will operate on any frequency between 6 and 80 meters. The PRV kit is well suited for outdoor and portable operations such as SOTA, Summits on the Air or POTA, Parks on the Air.

Chameleon PRV (Portable Resonant Vertical Kit):
https://chameleonantenna.com/shop-here/ols/products/cha-mcc

A Chameleon PRV POTA Kit was provided in exchange for this video.

PRV kit breakdown

The core component of the PRV or portable resonant vertical kit is the Multi Configuration Coil. The PRV is a base loaded antenna and the multi configuration coil, when paired with an appropriate sized whip, allows you to achieve a resonant match for any frequency between 6 and 80 meters.

The coil is constructed out of anodized aluminum outer body with a delrin center and stainless steel and silver clad copper wire. At first glance you will say this is Chameleonโ€™s knockoff of the Wolf River coil, but i believe it is more appropriate to compare the PRV kit and multi configuration coil with the Super Antenna MP1. The MCC is a more refined and elevated version of the MP1 coil, with the addition of being manufactured in the USA.

The coil itself is fairly lightweight, weighing in at just under 16 ounces and fully collapsed, it is 12 ยฝ inches long. At the base of the coil is a 3/8ร—24 male thread for attaching it to a base. Their is an SO-239 or UHF female connection for the coax, a thumb screw to lock the outer body of the coil to the center. This will keep it from slipping after you have a match. And finally, a 3/8ร—24 female receptacle for a whip. The choice of whip you use will determine the frequency range of the coil.

Chameleon sells the PRV kit in three different packages, the MCC coil by itself, the SOTA, or summits on the air light kit, and the POTA, parks on the air heavy kit.

Assembling the kit

Assembling your PRV or portable resonant vertical antenna is pretty straight forward. If you have any experience with other base loaded verticals this will seem familiar.

First off is the base or antenna support. The PRV kit comes with a ground spike you can push into the ground to support the antenna. If you are working with soft earth, this stainless steel spike will the coil and up to the 17 foot whip. But, if you are like me, and itโ€™s winter, or if you are operating on hard earth, or a durable surface like asphalt or concrete, the spike wonโ€™t work. The POTA heavy kit solves that with the UCM or universal clamp mount can be attached to anything with a lip, like a picnic table or bbq grill. The coil and whip can be deployed from that.

For my testing I preferred to use their new carbon fiber tripod. This is a lightweight portable tripod with extendable and adjustable legs. You can splay the legs out and it will easily support the coil and the PRV standard whip in most weather conditions. It will also support the 17 foot whip as long as it is not windy. If there is anything brisker than a gentle breeze, you run the risk of the tripod tipping over. Sand bags or weights on the legs will help prevent that. The tripod has a 3ร—8 x 16 course thread and ยผ inch male thread. These are standard tripod threads and the PRV kit comes with a ยผ inch to โ…œ inch fine thread adapter. You will use this adapter with the Chameleon tripod or any other tripod you wish to use.

Tuning

Tuning, or finding a good match, on your PRV can be easy, or it can be a challenge, it all depends on how you approach the process. Iโ€™ve had situations where the SWR in my vertical antenna drops down to nothing, and other times when it was a total bear and I canโ€™t get lower than 2:1. Iโ€™m going to tell you right now, itโ€™s not you, and often it is the location or ground conditions the antenna is on. That means if you are going to run with base loaded vertical antennas, you just need to accept that sometimes you wonโ€™t get perfect SWR, and in reality, anything less than 2:1 really is ok. Fortunately, Chameleon, with the PRV offers a fair amount of guidance in their user guide on how to get a good match on the various bands.

My experiences

So what is my experience with the Chameleon PRV or portable resonant vertical antenna? Iโ€™m going to say that I am very impressed. Honestly, this isnโ€™t a one off review of the antenna, but instead my opinions after using for a full month and making over 1000 contacts with it. There are some things that I like, and some that I donโ€™t.

First off, construction is top notch. This antenna is made in the USA and it shows with quality components. The multi configuration coil is well built, it is designed to handle up to 500 watts single sideband and 200 watts digital modes. I find that the construction of the coil and whip would support those claims. The documentation is excellent, it goes into great detail on how to tune and adjust the antenna, which is outstanding. The system is extensible, you can use it with the 58 inch whip, but I believe it really shines when you combine it with either the 9 foot Mil-Whip or 17 foot stainless collapsible whip. The 34 foot wire winder radial is innovative, but I think its also the weakest part of the package.

The problem I have with the wire winder radial is the weight. When you suspend it on a line from the elevated tripod to another support, you will need either a substantial tripod or to guy everything down as the weight of the winder on the line will pull the whole thing down. Since the ground was frozen during my test period, I couldnโ€™t guy things, so I struggled with deploying the elevated radial system.

But the elevated radial system also seemed to offer the best performance overall, so the effort to put it up is worth it. Properly deployed, I found it easy to get a match with the elevated radial as you werenโ€™t subject to the vagaries of ground conditions.

But I really like that the kit is extensible. You can add additional radials for better ground performance. I found that to really be a benefit for the 20 and 40 meter bands. You can use it with the magic carpet. I had a difficult time getting a good match with the faraday cloth and the 58 inch whip, but the ground screen worked great with the longer whips. And speaking of longer whips, I think the PRV is at its best when you use it with the 17 foot stainless or 9 foot mil-whips. I had no problems putting out great signals QRP, with only 5 watts of power using the long whips.

Bonus content and activation videos using the Chameleon MCC coil and the PRV kit are available to my patrons. Please visit my page on Patreon for details: https://www.patreon.com/kb9vbrantennas

Timestamp
00:00:00 Chameleon PRV Portable Resonant Vertical Antenna kit
00:00:57 CHA MCC Multi Configuration Coil
00:02:38 PRV SOTA Light and POTA Heavy Kits
00:03:36 Deploying the PRV POTA Heavy Kit with Extensions
00:05:52 Ground Spike, UCM, Carbon Fiber Tripod
00:07:55 PRV SOTA Light Kit Deployment
00:09:15 Tuning the MCC Multi Configuration Coil
00:11:01 Elevated deployment with the wire winder radial
00:12:35 My experience with the Chameleon CHA PRV POTA Kit

Like what you see? You can leave me a tip:
https://www.paypal.me/kb9vbr

Become a patron! Unlock exclusive content at: https://www.patreon.com/kb9vbrantennas

Support Ham Radio Q&A by shopping at Amazon: http://amzn.to/2kO6LH7

The post Everything you wanted to know about Chameleonโ€™s PRV Vertical Antenna Kit appeared first on KB9VBR Antennas.

Setting QRP on FIRE with the Chameleon OCF 40 Antenna

By: kb9vbr
28 February 2024 at 12:59

I head out to Dewey Marsh State Wildlife Area (POTA K-9840) with my QRP Yaesu FT-817ND to give the Chameleon OCF 40 Off Center Fed dipole antenna a test. The CHA OCF40 is a very lightweight and backpackable medium power antenna โ€” intended for extreme portable use, such as: Parks On the Air (POTA), Summits On the Air (SOTA), and other outdoor QRP radio adventures where an effective antenna is required.

Chameleon OCF 40 Off Center Fed Dipole Antenna: https://chameleonantenna.com/shop-here/ols/products/cha-ocf-40/v/CHA-OCF-40-ORANGE
Minus33 Merino Wool Fingerless Glove: https://amzn.to/47TZj1E
My favorite amateur radio gear: https://amzn.to/3QXrYgz

As a bonus, patrons can view the full, unedited phone contacts for this Parks on the Air activation. Visit my page on Patreon for details: https://www.patreon.com/kb9vbrantennas

I do return QSL, if you made a contact with me and would like a QSL, please send me one. Return postage not necessary, but always appreciated. As they say, KB9VBR is โ€˜good in the book.


Links may be affiliate links. As an Amazon Associate, I earn from qualifying purchases. This does not affect the price you pay.


Like what you see? You can leave me a tip:
https://www.paypal.me/kb9vbr

Support Ham Radio Q&A by shopping at Amazon: http://amzn.to/2kO6LH7

The post Setting QRP on FIRE with the Chameleon OCF 40 Antenna appeared first on KB9VBR Antennas.

New and Improved! Chameleon LEFS 4010 EFHW Antenna

By: kb9vbr
12 February 2024 at 13:12

I head to Council Grounds State Park (POTA K-1447) to test the new Chameleon LEFS 4010 end fed half wave antenna system. The LEFS or Light Weight Antenna System is a versatile EFHW HF antenna with tuner-free operation on 40, 20, 15, and 10 meters and can be used with a tuner on 60, 30, 17, and 12 meters. This lightweight antenna is specially good for low power, or QRP, operation and is small enough to be carried in your pack for portable POTA and SOTA adventures.

Chameleon LEFS 4010 Lightweight End Fed Sloper Antenna: https://chameleonantenna.com/shop-here/ols/products/cha-lefs-4010/v/CHA-LEFS-4010-NO-CX

My favorite amateur radio gear: https://amzn.to/3QXrYgz


Links may be affiliate links. As an Amazon Associate, I earn from qualifying purchases. This does not affect the price you pay.


Like what you see? You can leave me a tip:
https://www.paypal.me/kb9vbr

Become a patron! Unlock exclusive content at: https://www.patreon.com/kb9vbrantennas

Support Ham Radio Q&A by shopping at Amazon: http://amzn.to/2kO6LH7

The post New and Improved! Chameleon LEFS 4010 EFHW Antenna appeared first on KB9VBR Antennas.

Is this the best? Gabil GRA-7350TC Ultra Compact Vertical Antenna

By: kb9vbr
6 February 2024 at 12:56

We take the Gabil GRA-7350TC portable whip antenna and lightweight tripod up north with us to Madeline Island on the shore of Lake Superior (Big Bay State Park K-1439) to give it a test and see if this really is the ultimate in portable, packable, HF vertical antennas.

Read my updated thoughts on the Gabil antenna: https://www.jpole-antenna.com/2023/11/28/activation-log-the-gabil-antenna-maybe-its-not-so-bad/

Gabil GRA-7350TC 3/8ร—24 Portable HF antenna: https://amzn.to/4638Sd5
Gabil GRA-ULT01 MK3 Lightweight portable antenna tripod: https://amzn.to/472QXVh


Links may be affiliate links. As an Amazon Associate, I earn from qualifying purchases. This does not affect the price you pay.


Roasted Stuffed Squash Thanksgiving Bowl
1 acorn squash
1 medium onion
2 celery stalks
12 oz turkey (Oscaer Mayer carving board cuts work great)
1 package Stove Top stuffing mix
1 1/2 cup water
4 tbsp butter
1/4 cup pecans
1/4 cup dried cranberries

  1. Slice squash in half end to end. Scoop out inside and coat with olive oil and salt. Roast in a medium heat dutch oven for about an hour or until tender.
  2. Saute onion and celery until translucent. Slice turkey into small pieces and cook until warmed through.
  3. Add stuffing, water (or broth), and butter. Stir until stuff has absorbed liquid.
  4. Stir in pecans and cranberries. Add salt and pepper to taste.

Serve stuffing mix in the squash bowls.

As a bonus, patrons can view the full, unedited phone contacts for this Parks on the Air activation. Visit my page on Patreon for details: https://www.patreon.com/kb9vbrantennas

I do return QSL, if you made a contact with me and would like a QSL, please send me one. Return postage not necessary, but always appreciated. As they say, KB9VBR is โ€˜good in the book.

Like what you see? You can leave me a tip:
https://www.paypal.me/kb9vbr

Support Ham Radio Q&A by shopping at Amazon: http://amzn.to/2kO6LH7

The post Is this the best? Gabil GRA-7350TC Ultra Compact Vertical Antenna appeared first on KB9VBR Antennas.

Work 8 amazing bands with one antenna! CaHR Ares End Fed Random Wire

By: kb9vbr
24 January 2024 at 13:16

The folks are Coffee and Ham Radio did it again! This time with their Ares End Fed random wire (non-resonant) antenna. Whatโ€™s a random wire antenna and why would you want one? Letโ€™s talk about that as we put this antenna together.

Coffee and Ham Radio (CaHR) Ares Random Wire End Fed antenna:
https://coffee-and-ham-radios.square.site/product/cahrtenna-ares-random-wire-end-fed-/13

CaHR Ares Build Instructions: https://github.com/TemporarilyOffline/cahrtenna/blob/main/Ares%20Build%20Instructions.pdf

Ares is the Greek god of war. Also of courage. Thatโ€™s a mighty high aspiration to name an antenna after. But it seems fitting for an antenna, that when used properly, can be uncompromising and savage on the bands. The Ares is a random wire, or non resonant end fed antenna. It uses a 9:1 transformer at the feed point to match the impedance of the wire to the transmitter.

Coffee and Ham Radios sent me this antenna in exchange for a build and review video. Thereโ€™s no outside influence and my comments are my own.

But why a non resonant antenna? Donโ€™t antennas need to be resonant to operate. Thatโ€™s the cool thing about this style of antennas. If a radiator is not resonant on any of the bands it is intended for, it will have an impedance at the end of the wire of about 450-600 ohms. You can use an external tuner or matching device to resonate it on those bands. Back in the days of tube radios and open wire feed lines, it was easy to match the 450 ohm impedance of the random wire to your transmitter. Today, using 50 ohm coax, we use the 9:1 transformer and a tuner to accomplish the same task. Itโ€™s a really weird quirk that makes this style of antennas useful on a broad range of frequencies.

This is a pretty simplified explanation, Iโ€™ve got a video that goes into greater detail, I encourage you to check it out, the link is in the description below.

With that said, I have quite a bit of experience with and really love random wire or non resonant antennas, so Iโ€™m a bit excited to put this one together. Letโ€™s head to the bench, unbox the Ares antenna, assemble it, and give it a test.

Letโ€™s talk about wire length, because thatโ€™s the key to an effective non resonant antenna. If you look online, there are countless charts that give you preferred wire lengths based on which bands you wish to cover. These lengths have been mathematically calculated to not be resonant on any of the target frequencies you wish to use. But two lengths that are preferred are 41 and 71 feet.

With 71 feet of wire, and a tuner I can pretty much operate on any band between 10 and 80 meters. If my radiator is a shorter 41 feet long, then I have 40 through 10 meter support. There are other lengths that work. But these two lengths, 71 or 41 feet have the best mathematical combination for length vs band coverage.

The Ares now comes standard with enough wire for a 71 foot radiator along with a 28 foot counterpoise, approximately 100 feet of wire. Older models only came with 60 feet of wire. So the upgrade in wire length allows the freedom to choose between building an 80 meter or 40 meter antenna. I want 80 meter support, so Iโ€™m building mine with 71 feet of wire, but if you want an antenna with a smaller footprint, and 80 meters isnโ€™t a big deal for you, cut your radiator at 41 feet for 40 through 10 meter coverage

Resources

Random Wire Antenna Lengths: https://udel.edu/~mm/ham/randomWire/
Optimal lengths of random wire antennas: https://sprott.physics.wisc.edu/technote/randwire.htm

Tiger Sauce: https://amzn.to/46UIH9G

As a bonus, patrons can view the full, unedited phone contacts for this Parks on the Air activation. Visit my page on Patreon for details: https://www.patreon.com/kb9vbrantennas

I do return QSL, if you made a contact with me and would like a QSL, please send me one. Return postage not necessary, but always appreciated. As they say, KB9VBR is โ€˜good in the book.

=====================
Minnesota Wild Rice and Mushroom Soup

1 cup wild rice
4 slices bacon
1 large yellow onion diced
2 large celery stalks diced
2 large carrots diced
1 pound mushrooms sliced
2 cloves garlic
1 tsp oregano
2 tbsp butter
3 tbsp flour
1 cup white wine
1 bay leaf
2 tsp rosemary
4 cups chicken stock
1 cup heavy cream
1 tbsp vinegar
salt and pepper

In a separate pot add wild rice and 1 tsp salt to 2 cups boiling water. Cook for about 45 minutes or until done (authentic wild rice may take less time, read package directions).

Cut bacon into 1/4 slices and cook in large pot until fat is rendered. Remove to paper towel. Add vegetables to bacon fat and saute until onions are translucent 3-5 minutes. Add mushrooms and cook for additional 15-20 minutes until they develop a deep brown color.

Add butter, when melted add flour and oregano and stir until thickened. Add wine to deglaze pot. Add chicken stock, bay leaf, and rosemary. Cook for 20 minutes.

Add wild rice, heavy cream and simmer for another 10-15 minutes. Add vinegar, salt and pepper to taste. Serve with crackers.

Timestamp

00:00 CaHR Ares Random Wire Antenna
02:06 Unboxing the CaHR Ares Antenna
05:45 Assembling the random wire antenna
07:22 Non resonant Antenna wire lengths
08: 22 Deploying the antenna at Blue Mound State Park
10:09 17 meter contacts
12:15 15 meter contacts
14:08 40 meter contacts
14:47 20 meter contacts
17:10 Wild Rice and mushroom soup
18:10 How did it work?


Links may be affiliate links. As an Amazon Associate, I earn from qualifying purchases. This does not affect the price you pay.


Like what you see? You can leave me a tip:
https://www.paypal.me/kb9vbr

Become a patron! Unlock exclusive content at: https://www.patreon.com/kb9vbrantennas

Support Ham Radio Q&A by shopping at Amazon: http://amzn.to/2kO6LH7

The post Work 8 amazing bands with one antenna! CaHR Ares End Fed Random Wire appeared first on KB9VBR Antennas.

Your ultimate guide to the CaHRtenna Apollo End Fed Half Wave EFHW Antenna

By: kb9vbr
10 November 2023 at 13:18

I take a look at the Coffee and Ham Radioโ€™s Apollo End Fed Half Wave (EFHW) antenna. CaHRtenna EFHW is a 49:1 end fed antenna designed to operate on the 40 to 10 meter bands.

The god Apollo is one of the most important in Greek Mythology and is also the name of the Coffee and Ham Radioโ€™s flagship product, their end fed half wave antenna. The coffee and ham radio guys sent me one of their antennas to build, so letโ€™s put it together and get it on the air.

Apollo is the greek god of light. Also archery, truth, and poetry. These are some pretty lofty goals to attach a name to an end fed half wave antenna. But I have a feeling the Coffee and Ham Radioโ€™s Apollo antenna will live up to those expectations.

The coffee and ham radioโ€™s Apollo antenna is available online for purchase direct from them. They did send me this antenna in exchange for one of my 2 meter J-Pole antennas and a review, but my opinions are my own. This antenna comes as a kit, so you will have to assemble it before putting it on the air. All the parts are included, with the exception of some basic tools,

So letโ€™s head to the bench, unbox the Apollo antenna, assemble it, and give it a test.

Coffee and Ham Radio CaHRtenna Apollo EFHW: https://coffee-and-ham-radios.square.site/product/cahrtenna-apollo-end-fed-half-wave-/8
CaHRtenna Apollo Build Instructions: https://github.com/TemporarilyOffline/cahrtenna/blob/main/CaHRtenna%20Apollo%20Build%20Instructions.pdf
Coffee and Ham Radio Youtube Channel: https://www.youtube.com/c/coffeeandhamradios

Like what you see? You can leave me a tip:
https://www.paypal.me/kb9vbr

Become a patron! Unlock exclusive content at: https://www.patreon.com/kb9vbrantennas

Support Ham Radio Q&A by shopping at Amazon: http://amzn.to/2kO6LH7

Timestamp
00:00 CaHRtenna Apollo End Fed Halfwave
01:18 Unboxing the Apollo EFHW
04:02 Building the CaHRtenna Apollo
07:55 Deploying and Tuning
12:10 Making contacts
14:24 My Opinion and conclusion

The post Your ultimate guide to the CaHRtenna Apollo End Fed Half Wave EFHW Antenna appeared first on KB9VBR Antennas.

โŒ
โŒ