Results from Other Hams
Here you can find some information about the loop construction by different amateurs using AAA-1 kit or LZ1AQ loop amplifier.
All images are delivered kindly from hams around the world. I hope you can draw some ideas about antenna design and mechanical construction from them.
More details are available from the corresponding sites.
Links to reviews and practical constructions in magazines and sites:
- Radiorama, No.63/2016, review and practical design from Paolo Mantelli (in Italian)
- A Japanese transaltion of the article “Wideband Active Small Magnetic Loop Antenna” Thanks to Japanese hams who translate the article.
- QTC Amatörradio Sweden No2/2013 – a review in Swedish journal, from SM0JZT (in Swedish)
- QTC Amatörradio Sweden, No12/2015 – review and practical design, from SM5FQQ, SM5ACQ, SM5EFX (in Swedish)
- http://radiolawendel.blogspot.bg/2012/01/dalla-bulgaria-una-nuova-antenna-attiva.html – In Italian
- K9ZCE’s loop design with photos.
- IK0VVE’s loop design with photos.
- K6AVP’s loop design with photos.
- Article from DL4ZAO – in German.
AAA-1 is approved for use with SDRplay SDR
There are videos on the SDRplay YouTube channel where the AAA-1 was tested in loop mode and compared with other commercial loop antenna. A dual channel RSPduo was used for this purpose. This is also a demonstration how a dual channel SDRplay can be used to compare antenna performance.
Here are the links:
AAA-1C new Control board has an additional limiter to protect the receiver from very strong signals which limits the output signal to 10 dBm level in order to fulfill the requirements in SDR play specifications.
PA0HKZ: Simple way to use your enclosure
“I Found a simple way to use your enclosure. No drilling and no holes for connecting antenna. Use 3 PG 21 cable glands with nuts. They fit in the existing holes. I hope the pictures make things clear.”
ON5KQ: The battle against windmills!
“Since a few days, I installed my ON5KQ CW-skimmer at the new location. I used a large Loop arrangement with 4 loops. Each loops are made from 5m long piece of flexible 20mm thick hot-water pipe and connected following your advice to bring XL (Inductive reactance) down as much as possible. Mounted in vertical position just 3m above the a 15m roof out of steel. The steel roof has a size of 40x50m = 2000m2 and is next to a 160m saltwater canal, very close to the harbor of Zeebrugge, NorthSea. Please refer to attached pictures of the antenna site…
The antenna is very directive for vertical polarized local signals, so I can notch out the heavy power pulse noise of the wind energy farm very very close. The closest windmill with 4MegaWatt generator is only 90m far away !! Amazing, that with carefully turning the loop system, the noise can be almost completely eliminated !”
A Dual Polarization Crossed Loops Built by Paolo Mantelli
Qualche anno fa, mentre ero alla ricerca dell’antenna delle meraviglie, quella che tutti cercano, l’antenna magica che riceve tutto, su tutte le frequenze, l’antenna che tira fuori i segnalini dal QRM, quell’antenna che deve essere piccola, per stare nel piccolo spazio che abbiamo, ma grande nelle sue incredibili performance, ho incontrato per caso, navigando su Internet, un articolo di un Radioamatore Bulgaro: Chavdar Levkov LZ1AQ.
Read the full article (Italian): http://www.air-radio.it/radiorama/2016/Radiorama%20n.63.pdf
This is an element from PA3AKE’s phased array.
“A single loop measures 2.2uH, so in cross parallel could be 550nH. Maybe overkill, but it is an easy construction. I removed the outer insulation with a torch and a knife.”
PA1M: LZ1AQ actieve antenne versterker
Het wonen midden in een woonwijk is niet altijd even prettig als je zendamateur bent. Teveel buren te dichtbij en veel stoorbronnen vaak in de vorm van (plasma) televisies. Het storingsvrij luisteren op de lage amateurbanden op de zendantenne wat vaak een verticaal of (verkorte) dipool antenne is levert dan erg veel storing op. Als je kijkt met een SDR tussen de 1 en 3 MHz dan zie je heel veel stoorsignalen staan. Dit kan oplopen tot ver over de S9 op een aantal frequenties. Lastig als daar nu net het station zit waar je naar wilt luisteren of een verbinding mee wilt maken. Een aparte ontvangstantenne wil dan wel eens helpen en dan vaak in de vorm van een magnetische loop antenne. Zo heb ik er een aantal gebouwd.
Read the rest of the article (Dutch): http://www.pa1m.nl/pa1m/lz1aq-actieve-antenne-versterker/
M0CKE dual polarization
A New Homebrew Magnetic Receive Loop at VE1ZAC
The magnetic loop is very good antenna, with the lowest of low footprint and space requirements. Compared to the K9AY, it is a winner for me. If I had to pick one receive array of my three current ones… hmmm, it would really be a tough call.
Active receive antennas will be with me for the rest of my radio days, even if I have large amounts of space for antennas in the future. The new magnetic loop has remarkable performance for such a small footprint antenna. It is a keeper!
Read the rest of the article: http://www.ve1zac.com
Phased array at N2WQ
F2DX: Home-made 4 crossed loops + LZ1AQ’s Amplifier
Loop: 2/4 crossed loops each with 1m side. Tubes with diameter 14mm. L: 0.53uH. L of single loop 2.10uH.
The 4 loops system is now always connected to my QS1R + Skimmer Server, receiving 7 band at the same time.
The loop is 34m away from the most closely transmission tower. I used about 50 meters ofcat. 6cablebecause I had a roll in stock. It is composed of two screens (each around 2 pairs) + a ground wire that I connected to the base of the mast. The cable is buried in a sheath. I kept 5 meters more over the base of mast if I ever want to put the antenna higher.
LZ2ZG phased array
F-10255: Active Crossed Parallel Loops
Les premiers essais, avec pour antenne de référence l’end-fed décrite sur le site, permettent de constater que la loop fait généralement jeu égal avec cette dernière sur les bandes basses sans jamais être meilleure, tant du point de vue de la force du signal que du rapport signal sur bruit (en position double loop). A partir de la bande du 40m, l’end fed amène des signaux plus forts et un meilleur rapport S/B. La loop semble un peu moins sensible aux parasites orageux. Il convient de préciser que l’installation se trouve en zone résidentielle ; les antennes étant éloignées des habitations les plus proches d’environ 10m (QRA) à environ 50m (voisins). L’end fed fait 37,5m de longueur à 7m de hauteur, la loop d’environ 1,50m se trouve à 2m de hauteur.
Read the rest (in French): http://f-10255.pagesperso-orange.fr/antenne/lz1aq/lz1aq.htm
Mr. Tomas Andersson Sweden
Dave Gahimer (K9ZCE): Building a magnetic loop antenna & broadband amplifier for your SDR
Then there is the possibility of SDR chip damage from your 1.5 KW station! In researching Loops we came across LZ1AQ. A Brilliant design /engineer (http://www.lz1aq.signacor.com/). Deep reading sometimes, but a great understanding of what makes a good receiving loop antenna.
Those who chase DX know that sometimes fading is caused by the signals’ polarization changing in the Ionosphere. Having both vertical and horizontal loops, and the ability to combine both signals diminishes this fading problem. Being able to filter the powerful, commercial FM transmitters diminishes image problems. Clipping strong signals at the antenna from very near powerful antennas/transmitters could save the SDR receiver from damage.
Read the rest: http://swling.com/blog/2016/03/guest-post…
Mr. Daisuke Yasuhara Japan
The AAA-1 is installed at the HB9FX tower, as seen in the picture. I am using a passive antenna splitter from microcircuit and from there feeding several receivers. One of them is an SDR with public access under http://websdr.fvzr.ch:8901
Theo Druijven, Netherlands
“I received the antenna amplifier about 10 days at my home address in the Netherlands. I installed the antenna amplifier at my house. See attached picture. The antenna configuration is a crossed loop of about 80 cm diameter, made of 15 mm copper pipe with one vertical dipol.”
“The results are very good comparing to the former antenna amplifier. The old amplifier suffer for intermodulation products over the whole of the HF bands. With your amplifier its all cleared up and i can listen to very remote stations. At least if I catch a signal in the HF band, it’s a station and it’s no intermodulation product.”
“I made the antenna from 15 mm copper tubing. By bending the tube in small pre detemined angles, it became a full circle.
Antenna works perfectly! Even at 50 kHz.”
“I am indebted to Chavdar for both putting the design and the detailed analysis on the web and answering all my questions.”
“I used the plastic coated tube for its weather resistant properties. Performance is very acceptable and reduces my s/n level by many db,s on 80/160m bands.”
LZ2WO – RX phased array with 2 or 3 active AAA-1 loops 1 m diam. tube 14mm.
Phased with PA0SIM phaser or with Flex 5000 – dual RX mode.
AB5MF ex JH0BDK Mr. Sakae Obara
“Since I intend to use it only indoor, I used cheep materials such as soft styrene tube covered by kitchen aluminum foil as the element.”