New IR Remote Controlled QRP Magnetic Loop Antenna

[@sasines]

Very nice project and excellent workmanship. Nicely labeled and constructed. You have provided me with some great ideas for my own project. Thanks for sharing. 73 - Alan, W3AL

[@OM0ET]

Alan Sines Thank you Alan. Good luck with your project!

[@63snampook]

Very nicely made mag-loop. From what I understand however, it is not preferred to have the capacitor and the coupling loop on the same side of the main loop. Opposite to one another would be better...

[@OM0ET]

Yes thats truth. Would be better to place the small loop on top of the main loop but mechanically it was more complicated to me. 😉

[@vit777vit]

Piece or peace of mind? All together. I like it

[@OM0ET]

What do you mean?

[@vit777vit]

@@OM0ET I mean it is very nice, simple device and good result

[@OM0ET]

@@vit777vit Thank you :) 73 Paul

[@andreg6594]

Hallo tolles Projekt, wäre es bitte möglich den Schaltplan für die Motorsteuerung mit den Relais zu veröffentlichen ? Vielen Dank und bitte weiter so. 73 Andre

[@OH8STN]

absolutely brilliant design. can you tell us the range of the ir transmitter? thanks for sharing.

[@OM0ET]

OH8STN Hi, thank you! I don't no exactly, but tryed it within 5 meters when was IR led uncovered out of box. Next depends on your IR cover.

[@OH8STN]

I think 5 meters is good. I was thinking of adapting your design for a portable system. Thanks again and new subscriber.

[@OM0ET]

I am very glad! ;-) You will need put in some rechargable battery. Maybe some small LiIon with charging module from Aliexpress. I wish you good luck with your own project :)

[@NamasenITN]

Can you post information on the wire thickness, the air capacitor model, and the choke ?

[@OM0ET]

Wire thickness is 2,5mm. Is used old russian ceramic air capacitor 50pF and choke is random from home store (from PC PSU probably).

[@MoondancerRec]

Add a light pipe and you can set the loop in places out of direct line of sight

[@OM0ET]

Gabriel Sierra that's a good idea!

[@MoondancerRec]

Thanks! I use a home made syringe driven trombone capacitor and It is a great thing to sit in front of the radio and remotely tune the loop.

[@DavidGillooly]

Very nice construction job!

[@OM0ET]

David Gillooly thank you David ;-)

[@jimawhitaker]

Nice workmanship.

[@OM0ET]

thanks, but it's not yet tested in the real conditions - outdoor. Hope it will works. :)

[@barretto4152]

How well has the efficiency turned out to be since you've had it for a while? Is it worth it? Have you made a few contacts? I may make one myself maybe with copper Tubing and spread the two turns apart a little.

[@OM0ET]

I didn't use this antenna for so long, but I had a couple of contacts across the Europe from the table at my room :-) But better is working my 1m diameter loop which I use now :-) The efficiency of this remote magloop should be not high due to a small diameter of the loop, but it works :)

[@spiritcore1]

Very nice! How the 2 turns of the loop works? what's the difference from 1 turn? What's the diameter of the loop and the circumference? Thank you!

[@OM0ET]

Hello, diameter of both turns is 45cm, small loop diameter is 9cm and the gap between main loop turns is 4cm. Difference between one or two turns is in its final inductivity and size of antenna. But this construction is very small and effectivity of this MLA is very low. I recommend to you to build this one: kzbin.info/www/bejne/fHi6d3RnZ9eEa68

[@spiritcore1]

Thank you! I'll watch it. You have very interesting videos... Just watched the EH antenna one.

[@OM0ET]

Thank you! The EH antenna is practically not working until now, because i dont know how to solve the issue with the strong RF in the feed line(coaxial cable). Its causing a strong resonance unstability. I need to isolate RF between EH antenna and the coax.

[@spiritcore1]

Yes, I read the comments. Also read what someone there wrote on his website (I didn't understand half of it HI) that EH antenna isn't really radiating... I thought I fount the a magical antenna :) 73.

[@OM0ET]

About 15yrs ago i made the CB EH antenna and i did a QSO with 4W to U.K. CB station from inside of my room on 1st floor of the 3 floor building. So there is no doubt that EH antenna is really working. But the design was much different like this one.

[@VE3IPS]

very innovative and looks like some brilliant building. How big are the loops? and i love how you wired out the pl-239s

[@OM0ET]

Thank you! :-) The main loop is variable in size, because of PL connections. In this case was used 2 turns abt. 30cm in diameter loops. It's just experimental antenna. Better would be to use Bluetooth (WiFi) remote controller.

[@alexramos2568]

Why 8 relays and not just 4?

[@OM0ET]

4 chinese blue releys are just with one switching contact each. Transparent 4 releys have two contacts each. Transparent releys are switching voltage polarity in to DC motor. You can't do this with only one contact, you will need two of them. ;-) That's why are there 8 releys total. 73 Paul

[@digitaldreamer5481]

Aloha Paul, can this micro loop antenna be made for 10 meters only and how many watts can be transmitted? I believe you are going to modernize the entire Amateur radio hobby with your loop antennas. 😎

[@OM0ET]

This was just an experiment but it was capable to use more that 50 or even 100W due to very large capacitor in the box, but using such a big power so close to the human body would be dangerous. I dont have this antenna any more. Scraped 😃

[@digitaldreamer5481]

@@OM0ET Oh no!!! What a beautiful antenna and would have been perfect for my Xiegu G90 at 1-20 watts PEP. Plus I could of added a 7 a/h UPS battery and connect it to a folding solar panel for SOTA activations. Can you dig it out of the trash pile and give it to me? 😂🤣😂🤣

[@OM0ET]

@@digitaldreamer5481 lol 🤣 impossible! Unfortunately but parts doesn't exist anymore 😃

[@TrystansWorkbench]

Paul, this is a very interesting and instructive video. I have been experimenting with a magnetic loop antenna for around a week or so that's how I found your video. May I ask a question please? With the 50pF capacitor, what bands can you tune to? 73 Trystan G0KAY

[@OM0ET]

Trystan's Workbench thank you! MLA antenna is like a LC circuit and its resonance depends on capacity and inductance. There is also some optimal values for each bands. But if you will use more inductance you can use less capacity. There are plenty of online calculators on the web. There you can see what you can do with 50pF capacitor. But 50pF is not really a big value for MLA. Could be working well on 12, 11 or 10m bands with one turn of copper wire. 😉

[@TrystansWorkbench]

Paul, Thank you, and for your very fast reply too. Yes! So making two turns means you can go to 20m bands and lower? Do you need to alter the size of the Faraday loop if you go from one turn to two turns, and does the position of the faraday loop have to be changed if you do that (on your two loop it's near the capacitor for your two-turn loop)?

[@OM0ET]

The small loop position is this due to better construction capabilities but the best position is to place coupling loop against to capacitor. And about 2 turns - there have to be the optimal values and high Q of the antenna and its efficiency. The best is to use 1turn and good capacitor. But you have to calculate.

[@OM0ET]

In my case it was not a really good idea to do so as i did.

[@OM0ET]

Let see my latest videos with UltraLight MLA design. This antenna is working perfect!

[@sergey7331]

Hi! In order to measure the SWR properly, you have to switch to FM. Or you have to modulate the SSB signal by long "AAAA". By the way, have you passed a QSO on this antenna? I haven't seen more videos with this antenna.

[@OM0ET]

There was a mistake when i measured the SWR on SSB but after a few seconds i measured it on carrier modulation. Maybe you didn't seen whole video. I did couple QSOs with this loop but i don't recorded it on the video.

[@kschildt1]

Very Nice. Gave me some great ideas.

[@OM0ET]

Thank you Kenneth! Good luck with your next project ;-)

[@pochonietypasjomrutusultim5875]

Wow 😲

[@NamasenITN]

I think the radio (and yourself) are too close to the radiating elements. It is both technically and biologically unsafe.

[@ok2aqa731]

Moc pěkně vyřešeno! palec nahoru ;-) 73 OK2AQA - moje MLA ok2aqa.rajce.idnes.cz/Magnetic_loop_antena_pro_kv_7_-_28Mhz/

[@OM0ET]

OK2AQA Dakujem. Pozrel som si tvoju MLA. Aka je sirka pasma na 40m?

[@ok2aqa731]

když přidám přepínačem pevnou kapacitu, obsáhne ladící kondenzátor pásmo od 6,980 až cca 12,000 Mhz.

[@OM0ET]

Skor som myslel ako je "ostrá" na 40m pasme. Povedzme ze od SWR 1:1.5 do 1:1.5

[@ok2aqa731]

Aha, ladí opravdu sakra ostře a vyladím to na 1:5, ale stačí se odladit o pár KHz vedle a musím doladit, nejlépe to ladí na 20m, tam mám také 90% spojení, tam je to 1:4. Ale nemám analyzátor, tak je to jen podle ucha a SWR :-(..... Na 10m je to už 1:7

[@OM0ET]

OK2AQA Ano. Chystam sa postavit MLA na jedno pasmo - 40m. Pravdepodobne sirsia Cu trubka a vzduchovy kondenzator ladeny po kabli. V pivnici mam stale funkcnu takmer profi AL verziu MLA z Nemecka na 100W. Ta funguje od 14 do 29MHz. Je velmi pevna a 3 roky som ju mal na streche a pouzival ju ako hlavnu antenu az kym som ju nevymenil za HEXBEAM. Ta vsade ladi na 1:1 ale ako vsetky MLA je tie dost ostra.