That's great to hear. Having the height of your antenna and using a signal like the Digital modes /CW, is ideal for an antenna like this with its tight Q. I was able to make some SSB contacts but it was a struggle. Thanks for letting me know.
I have homebrewed mag loop antennas. Just looking at the dimensions of this one, it is hard to imagine that it could handle any power. The air variable caps needed for QRO operation have to be much larger to accomodate the greater plate spacing. A piece of large diameter coax gives you a larger diameter of radiator than a simple wire but far below what a high end loop will require. Ideally the loop capacitor will either be a vacuum variable or a butterfly design. A common air variable introduces additional losses. This gives you a less efficient radiator. The end result is that you have a better receive antenna than a transmit antenna. Tuning these loops by ear will work to a certain extent. However, you need a NanoVNA or an antenna analyzer to tune properly and maximize the potential of the loop.
The type of capacitors this uses is the the polyvaricon (sp?) variety. You're right, it can't handle much power. About 5 to 10 watts CW and 10 to 20 watts SSB. And because of the size of the loop, it is better at 20 meters than 40. I have a G90 which has SWR reading capabilities - very easy to use - making tuning a little easier. But, this was not the best loop antenna which is why I sold it. It was interesting to play with and I'm glad I had it for a while but I have moved on. Thanks for replying.
@@rbashta Thank you very much for buying this loop and sharing your experiences. To get good performance from small transmitting loops requires meticulous attention to design, construction and materials. Otherwise, loops will prove to be less efficient radiators. Coupled with low power, there may be stations that you can hear when they cannot hear you.
Ну, на счёт переменных конденсаторов вы совершенно правы. Эта антенна представляет собой параллельный колебательный контур, при чём с относительно высокой добротностью. По этому, при резонансе, Э.Д.С. там может достигать единиц киловольт, при мощности передатчика в десяток ватт. Да, лучшим решением будет вакуумный КПЕ. Но, а на счёт антенных анализаторов, то это лишне. Обычно такая антенна настраивается следующим образом - в режиме приёма, по максимальному уровню шумов или сигнала корреспондента. А потом даётся малой мощностью несущая и окончательная настройка по минимуму КСВ. Такие антенны узкополосны - полоса пропускания 15...30 килогерц и на ось конденсатора надо установить хотя бы простейший верньер с передачей 1к3 или 1к10. Я экспериментировал с такими антеннами и лучшие результаты это рамка с петлёй связи. Удачи, 73!
Alex - thanks for your note. These loop antennas are quite interesting with their good points and bad ones. I enjoyed playing with this antenna but eventually sold it. I mainly use an end fed for a lot of my work. 73
Sometimes when it is storming outside and dangerous to operate when Zeus is busy shocking the earths surface I think about having a loop like this at my bedside with a little QRP transceiver. Definitely portable and field expedient
Thanks for your helpful video. One suggestion I'd make is that you carefully clean your lens with a soft damp cloth (either water or lens cleaning fluid) and you'll improve the video quality significantly.
Thanks for the comment. I would re-do the video but I have sold the antenna. To be honest, there are some plus and minuses to this antenna. It works the best when outside and close to the ground. But it needs constant tweaking to get on frequency. I do best with my QRP Guys end fed which requires only a 25 foot wire.
i only need it to recieve not transmit i have space for about 20 foot long wire so maybe the loop would be better to revieve not sure ..longwire is much cheaper i live in a apt loop would be in front of a window.
The loop antenna works better for receiving than transmitting but is still very directional and has to be retuned every time you change bands and frequencies. A long wire antenna does not have that issue. I will say that this antenna has a very sharp Q and is good at reducing interference from other signals around the station you’re trying to listen to. I will also say that there are larger loop antennas on the market which work better than this one.
*Hello dear friend! Please tell me, what is the maximum power of this magnetic antenna? There are different data on Aliexpress . Someone writes 5 watts and someone writes 20 watts. Will this antenna work for transmission in the apartment of a reinforced concrete apartment building? Thanks!*
Thanks for the question. I had the same one originally. This antenna can handle up to 20 watts SSB and 10 watts CW. However, this amount of power is right at the threshold of causing the capacitor plates from arching over. To operate at a safe amount of power, I would use 10 watts SSB and 5 watts CW.
For me, I found this antenna worked best outside - away from buildings - and with the antenna sitting close to the ground, to take advantage of the earths magnetic presence. I have seen these antennas work inside a building but only if it is close to a window. Good luck.
The diagram I show is pretty much the schematic of the loop antenna. The loop uses the shield of the loop cable with a variable capacitor attached to the ends. The variable capacitor is actually two. When using 40 meters, one side of the variable capacitor is shorted. And then when using 20 meters, the switch is open, both variable capacitors are used. There are wires connected to both ends of the cable which go to the radio antenna connection. There is one variable capacitor connected in series with one of the leads to the radio. This capacitor is for matching the SWR of an antenna. I hope this helps.
I sold it a month ago. It was fun to use but I had better luck with an end fed antenna I use for QRP POTA work. Just remember to use it near a window or on a balcony. Tune for the loudest signal and make sure your SWR is below 1.5. Also, it is very directional. And don't touch it when transmitting. You will get a shock. You don't need that. It will work decently if the propagation is good. I did make an inner loop which you do see on a lot of mag loops and that can work a bit better. Good Luck.
There are larger mag loops on the market, like the Chameleon or the Alex Loop, which have a diameter of 1 meter. They can do 80 meters. The larger loops can also handle up to to 100 watts. This QRP mag loop has a diameter of less than 3/4 of a meter - 70 centimeters to be exact. It is one of the smallest mag loops out there. Those larger loops go for about $ 500. This one cost $ 139.
@@rbashta What you've got there is about $50 in parts, if all need is longer coax for the loop, then we might get up to $60. I was considering this loop as it is pretty cheap. I have not seen inside the little box but I suspect it will contain two cheap polycon variable capacitors, a switch and a pair of SO239's. MFJ make a cheap nasty loop tuner and it is very much the same. IE a handful of cheap parts and a tin box. It seems that hams have forgotten how to make make things and your credit card is an essential tool as they seem to have forgotten how to MAKE the gear they use.
@@G7VFY Unfortunately peoples use to pay tons of money for something that they can make on theyr own , involving 1/5 of the money . Alot peoples buy the alexloop and somm like that for $500 and up wich is totally insane and NO sense to me . They pay loads of money for a lenght of a shielded cable and a cheap variable cap ..this is because they don't know about the skin effect of the rf ..so by this everyone can understand that a solid copper tube is one thousand times better than a coax . Oh yes, but the coax version is for portable use . LOL and you pay $500 because you won't make it yourself ? Hey, it's a 1m of coaxial cable and a cheap boxed variable cap ! To me, those hams really should woke up .
@@adrianoragazzo1321 People still do. They MAY pass an exam, but they still seem to have no clue or interest in making some of the most basic and common tools and station accessories. A coax loop pocket money parts, assuming that you don't have the parts already. Appliance operators, the credit card is the only tool they've mastered.
@@adrianoragazzo1321 A lot of hams have physical limitations and are unable to even do the soldering so back off!! I hope that you never have a debilitating condition to the point where you need help to take a piss or are unable to perform any ham related tasks.
I’ve run this antenna up to 10W on FT8. Managed to get transatlantic FT4/8 QSOs from a bedroom in a 4th floor apartment.
That's great to hear. Having the height of your antenna and using a signal like the Digital modes /CW, is ideal for an antenna like this with its tight Q. I was able to make some SSB contacts but it was a struggle. Thanks for letting me know.
I have homebrewed mag loop antennas. Just looking at the dimensions of this one, it is hard to imagine that it could handle any power. The air variable caps needed for QRO operation have to be much larger to accomodate the greater plate spacing. A piece of large diameter coax gives you a larger diameter of radiator than a simple wire but far below what a high end loop will require.
Ideally the loop capacitor will either be a vacuum variable or a butterfly design. A common air variable introduces additional losses. This gives you a less efficient radiator. The end result is that you have a better receive antenna than a transmit antenna.
Tuning these loops by ear will work to a certain extent. However, you need a NanoVNA or an antenna analyzer to tune properly and maximize the potential of the loop.
The type of capacitors this uses is the the polyvaricon (sp?) variety. You're right, it can't handle much power. About 5 to 10 watts CW and 10 to 20 watts SSB. And because of the size of the loop, it is better at 20 meters than 40. I have a G90 which has SWR reading capabilities - very easy to use - making tuning a little easier. But, this was not the best loop antenna which is why I sold it. It was interesting to play with and I'm glad I had it for a while but I have moved on. Thanks for replying.
@@rbashta Thank you very much for buying this loop and sharing your experiences. To get good performance from small transmitting loops requires meticulous attention to design, construction and materials. Otherwise, loops will prove to be less efficient radiators. Coupled with low power, there may be stations that you can hear when they cannot hear you.
Ну, на счёт переменных конденсаторов вы совершенно правы. Эта антенна представляет собой параллельный колебательный контур, при чём с относительно высокой добротностью. По этому, при резонансе, Э.Д.С. там может достигать единиц киловольт, при мощности передатчика в десяток ватт. Да, лучшим решением будет вакуумный КПЕ. Но, а на счёт антенных анализаторов, то это лишне. Обычно такая антенна настраивается следующим образом - в режиме приёма, по максимальному уровню шумов или сигнала корреспондента. А потом даётся малой мощностью несущая и окончательная настройка по минимуму КСВ.
Такие антенны узкополосны - полоса пропускания 15...30 килогерц и на ось конденсатора надо установить хотя бы простейший верньер с передачей 1к3 или 1к10.
Я экспериментировал с такими антеннами и лучшие результаты это рамка с петлёй связи.
Удачи, 73!
Alex - thanks for your note. These loop antennas are quite interesting with their good points and bad ones. I enjoyed playing with this antenna but eventually sold it. I mainly use an end fed for a lot of my work. 73
Sometimes when it is storming outside and dangerous to operate when Zeus is busy shocking the earths surface I think about having a loop like this at my bedside with a little QRP transceiver. Definitely portable and field expedient
Thanks for your helpful video. One suggestion I'd make is that you carefully clean your lens with a soft damp cloth (either water or lens cleaning fluid) and you'll improve the video quality significantly.
Very helpful. Thanks for posting. Look forward to receiving mine. 73.
This was so helpful. Thank you very much for your explanations. 73
Thanks for letting me know
Thanks for the good info, but I would have loved to hear it in action. Thx, Brent
Thanks for the comment. I would re-do the video but I have sold the antenna. To be honest, there are some plus and minuses to this antenna. It works the best when outside and close to the ground. But it needs constant tweaking to get on frequency. I do best with my QRP Guys end fed which requires only a 25 foot wire.
i only need it to recieve not transmit i have space for about 20 foot long wire so maybe the loop would be better to revieve not sure ..longwire is much cheaper i live in a apt loop would be in front of a window.
The loop antenna works better for receiving than transmitting but is still very directional and has to be retuned every time you change bands and frequencies. A long wire antenna does not have that issue. I will say that this antenna has a very sharp Q and is good at reducing interference from other signals around the station you’re trying to listen to. I will also say that there are larger loop antennas on the market which work better than this one.
The wire would be much cheaper and less directional.
Would you be able to put a link for the antenna in the description ?
*Hello dear friend! Please tell me, what is the maximum power of this magnetic antenna? There are different data on Aliexpress . Someone writes 5 watts and someone writes 20 watts. Will this antenna work for transmission in the apartment of a reinforced concrete apartment building? Thanks!*
Thanks for the question. I had the same one originally. This antenna can handle up to 20 watts SSB and 10 watts CW. However, this amount of power is right at the threshold of causing the capacitor plates from arching over. To operate at a safe amount of power, I would use 10 watts SSB and 5 watts CW.
That Element IS NOT AbOUT A METER LONG, More Like Two Meters Or 1.5Meters !
*Hello! I bought such an antenna. Why doesn't she work for me on the show? SWR 1.5*
For me, I found this antenna worked best outside - away from buildings - and with the antenna sitting close to the ground, to take advantage of the earths magnetic presence. I have seen these antennas work inside a building but only if it is close to a window. Good luck.
hello, is there a more detailed diagram of the antenna on which the toggle switch is indicated?
The diagram I show is pretty much the schematic of the loop antenna. The loop uses the shield of the loop cable with a variable capacitor attached to the ends. The variable capacitor is actually two. When using 40 meters, one side of the variable capacitor is shorted. And then when using 20 meters, the switch is open, both variable capacitors are used. There are wires connected to both ends of the cable which go to the radio antenna connection. There is one variable capacitor connected in series with one of the leads to the radio. This capacitor is for matching the SWR of an antenna. I hope this helps.
Any updates? Still working for you? I have one on order from China. Expected delivery by the end of this month. Bought it for apartment use.
I sold it a month ago. It was fun to use but I had better luck with an end fed antenna I use for QRP POTA work. Just remember to use it near a window or on a balcony. Tune for the loudest signal and make sure your SWR is below 1.5. Also, it is very directional. And don't touch it when transmitting. You will get a shock. You don't need that. It will work decently if the propagation is good. I did make an inner loop which you do see on a lot of mag loops and that can work a bit better. Good Luck.
Grazie per il tuo video ,adesso mi sento più sicuro di aquistare questa antenna
Grazie e 73 de IZ7QUC Antonello
Prego. Questa antenna funziona meglio per CW. Visiterò l'Italia ad ottobre e porterò una radio. Spero di lavorarti. 73 de N1KRB
2023 :-)
I wonder how big you would need to make the coax loop to cover 80m? G7VFY
There are larger mag loops on the market, like the Chameleon or the Alex Loop, which have a diameter of 1 meter. They can do 80 meters. The larger loops can also handle up to to 100 watts. This QRP mag loop has a diameter of less than 3/4 of a meter - 70 centimeters to be exact. It is one of the smallest mag loops out there. Those larger loops go for about $ 500. This one cost $ 139.
@@rbashta What you've got there is about $50 in parts, if all need is longer coax for the loop, then we might get up to $60. I was considering this loop as it is pretty cheap. I have not seen inside the little box but I suspect it will contain two cheap polycon variable capacitors, a switch and a pair of SO239's. MFJ make a cheap nasty loop tuner and it is very much the same. IE a handful of cheap parts and a tin box.
It seems that hams have forgotten how to make make things and your credit card is an essential tool as they seem to have forgotten how to MAKE the gear they use.
@@G7VFY Unfortunately peoples use to pay tons of money for something that they can make on theyr own , involving 1/5 of the money . Alot peoples buy the alexloop and somm like that for $500 and up wich is totally insane and NO sense to me . They pay loads of money for a lenght of a shielded cable and a cheap variable cap ..this is because they don't know about the skin effect of the rf ..so by this everyone can understand that a solid copper tube is one thousand times better than a coax . Oh yes, but the coax version is for portable use . LOL and you pay $500 because you won't make it yourself ? Hey, it's a 1m of coaxial cable and a cheap boxed variable cap ! To me, those hams really should woke up .
@@adrianoragazzo1321 People still do. They MAY pass an exam, but they still seem to have no clue or interest in making some of the most basic and common tools and station accessories. A coax loop pocket money parts, assuming that you don't have the parts already. Appliance operators, the credit card is the only tool they've mastered.
@@adrianoragazzo1321 A lot of hams have physical limitations and are unable to even do the soldering so back off!!
I hope that you never have a debilitating condition to the point where you need help to take a piss or are unable to perform any ham related tasks.
I buy It buy swr Is too much.