Medium wave beam?
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I doubt many commercial options exist, due to the size required, and very limited market.
Using an HF beam, with a low pass filter might be a reasonable option.
Here is a story about a beam for 160m, which is close to the AM BCB.
Just saw this blog post, from a few days ago, about a vertical 160m beam.
w0qlremotebase.wordpress.com
Vertical Yagi For 160 Meters
Were you imagining a horizontal yagi at 270 feet in the air? No way. It is actually a vertical yagi, meaning three 160m vertical antennas are in a line and spaced a typical distance apart for a yag…
w0qlremotebase.wordpress.com
The laws of physics almost never permit “medium wave” and “compact” to exist in the same paragraph. If directionality and lower noise on medium wave is what you’re after, start here -
wiki.radioreference.com
Then read nearly everything in this RR Forum:
forums.radioreference.com
Loops - The RadioReference Wiki
Receive Antennas (below 30MHz)
For all topics related to receive antennas used on HF, MW, LW, etc. For transmit antennas use the Amateur Radio Antennas forum.
that's what i was starting at, can i make a cubical quad using air wound loops to reduce space?The laws of physics almost never permit “medium wave” and “compact” to exist in the same paragraph. If directionality and lower noise on medium wave is what you’re after, start here -
Loops - The RadioReference Wiki
ka3jjz
Wiki Admin Emeritus
ROTFL!
Tell you what - here's a hint. Do the math for the sizes and spacing, and see what your results would be.
While the loops wiki has loops that cover MW, there are many other MW related antennas - including the K9AY...
wiki.radioreference.com
Mike
Tell you what - here's a hint. Do the math for the sizes and spacing, and see what your results would be.
While the loops wiki has loops that cover MW, there are many other MW related antennas - including the K9AY...
MW DXing and Broadcasting - The RadioReference Wiki
Mike
I'll save him the trouble: ONE SIDE of a quad antenna at 1500 kHz would be about 172 feet. And don't forget... for the antenna to work properly you'll need to get it into the air.... at least 40-60 feet up. But, I acknowledge your reference point for "compact" may be different than mine (e.g. football field and several towers vs a small island... and several towers). And don't forget.... you'll probably want to rotate the entire antenna since it is highly directional. If in fact you do have several football fields of space to work with, it would be simpler to make a rhombic antenna.
n5ims
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Depends on why you want a "beam". If you simply want an directional antenna there are plenty examples of directional medium wave antenna systems. Many AM broadcast stations use them quite effectively. That said, they're not cheap and take quite a bit of land area. Be aware that the tower layout and spacing is critical for a good dependable radiation pattern. You'll also need several tall towers for your system. Some only have a couple of towers for a simple pattern while others may have as many as 12 towers to get the pattern correct. This is one example for KFXR 1190 in the Dallas TX area. Bing Maps - Directions, trip planning, traffic cameras & more These take loads of cash and land to do so they're not for the faint of heart. Also note that you'll need to have your towers registered with the FCC and FAA and properly marked since they'll nearly certainly be over 200' tall.
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You can build a 4 Square system. You use four vertical antennas and a phasing system to adjust the directional pattern. You install the phasing switches out in the field and control it with a small box in the shack. It's possible to 'beam' your signal in 8 directions. They do work on the 160 meter ham band (which is MF). https://lowbandsystems.com/product/controller-lbc8-4square-8dir
If you're just interested in one direction only and have a sizeable acreage, a wire antenna like the Rhombic would work. https://www.mapability.com/ei8ic/rhombic/text.php
If you're just interested in one direction only and have a sizeable acreage, a wire antenna like the Rhombic would work. https://www.mapability.com/ei8ic/rhombic/text.php
I apologize for any gender misidentification.... I should have referred to you as "the OP" (Original Poster). And I'm sorry for any perception of rudeness... it was not my intention. You did receive not only reference information regarding the practicality of medium-wave quad antennas, but also further places for research and practical alternatives for directional antennas in the medium-wave band. I hope you'll see fit to continue to use RR as a source of information and discussion in the future. Your presence and questions are always welcome.
How compact do you have in mind? There will be a trade off of lower performance for a smaller size, which can be somewhat aided by filters and pre-amps. I'm not sure where the cliff effect would come into play.
I just connected the OP's post other post on medium wave listening with this one, It appears that she wants the antenna for Broadcast Band listening. In that case a loop would probably be the best antenna to use. (See the links popnokick supplied in his post above). Most loops have a figure 8 pattern so they are directive to some degree.
I'm a long time BCB DXer. I picked up a Wellbrook ALA100 active receiving loop a few years back. It was great at digging out weak signals. Within a few weeks I added a dozen new stations to my 18 year old BCB receiving log. Prior to that, it got to the point where I was hearing the same stations over and over again.
While it's a great antenna, the Wellbrook is kind of overpriced and is made in England.. There are North American made loops like the W6LVP model. It seems to be quite popular here on RR.
I'm a long time BCB DXer. I picked up a Wellbrook ALA100 active receiving loop a few years back. It was great at digging out weak signals. Within a few weeks I added a dozen new stations to my 18 year old BCB receiving log. Prior to that, it got to the point where I was hearing the same stations over and over again.
While it's a great antenna, the Wellbrook is kind of overpriced and is made in England.. There are North American made loops like the W6LVP model. It seems to be quite popular here on RR.
wow, that's way better of a response than i honestly expected. That speaks very well of the rr crowd. Usually i get nasty responses when i try to correct someone. It's cool when you're pleasantly surprised by kindness. Thanks for the warm feels.
I had a lot of help over the years in my ham radio interests & pursuits... and try whenever I can to return the help to fellow hams. Keep us posted on what you have tried / try / will try for your medium wave antenna(s). Everyone here is genuinely interested, and many in the "same boat".
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