Would it be good to go with a stacked array of Yagis with elevation and rotational control? Or would a dish type array be a better route. And, what is the recommended power to use with the VHF/UHF EME? It'll be awhile before I can get everything setup, but I wanted to know what other hams that have done EME have had the best luck with. I saw a nice set of dish antenna plans in an old QST magazine from 1974. Any suggestions?
Or has EME become more a niche and less common?
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Obi-wan "You were the chosen one. It was said you'd destroy the Sith, not join them. Bring balance to the Force, not leave it in darkness."
Would it be good to go with a stacked array of Yagis with elevation and rotational control? Or would a dish type array be a better route. And, what is the recommended power to use with the VHF/UHF EME? It'll be awhile before I can get everything setup, but I wanted to know what other hams that have done EME have had the best luck with. I saw a nice set of dish antenna plans in an old QST magazine from 1974. Any suggestions?
Seriously, like I'd be able to do that. I wish I could.
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Obi-wan "You were the chosen one. It was said you'd destroy the Sith, not join them. Bring balance to the Force, not leave it in darkness."
Yep, I copied their 80 meter EME signal, so I guess I've done EME with just a dipole.
I haven't gotten a Round Tuit yet, but I've read that it's possible to make an EME QSO with quite a few well-appointed stations using only 100 watts and a single yagi. Just like copying the HAARP signal, the other station is doing the heavy lifting.
To get serious, the antenna system requirement depends on several things:
-Which band you want to work?
-Are you satisfied working just the "big guns" with 30 dB antenna systems or would you like to routinely work lots of stations, including "non-"big guns?
-Are you satisfied making contacts without actually hearing your own lunar reflection?
It is true that using JT-65, a specialized digital mode optimized for e.m.e. work, you can make contacts via the moon using a fairly modest station, as long as you can work the mode and aim "something" at the moon: Even a single 13 dB Yagi and 100W can be enough to work other stations who are a bit better equipped. That was almost never possible before WSJT coding was developed.
However, in doing that you probably won't hear your own reflection, and operating JT-65 still takes some skill as well as reasonably good weak signal equipment (very stable, very accurate, very sensitive, SSB-CW gear).
Normally dish antennas aren't employed even for e.m.e. on any band below 70cm, and not that many moonbouncers use dishes even there. They're more commonly employed where reasonably sized ones can have a lot of gain, like 2.3 GHz and above.
Stacked yagis, quads, quagis and loop yagis are far more common at 1.2 GHz and below.
Moonbounce antennas are very rarely installed where they cannot be reached, such as on a tall tower. No need to put them up there, and if they're out of reach they're much more of a pain to adjust, optimize, etc.
To get serious, the antenna system requirement depends on several things:
-Which band you want to work?
-Are you satisfied working just the "big guns" with 30 dB antenna systems or would you like to routinely work lots of stations, including "non-"big guns?
-Are you satisfied making contacts without actually hearing your own lunar reflection?
It is true that using JT-65, a specialized digital mode optimized for e.m.e. work, you can make contacts via the moon using a fairly modest station, as long as you can work the mode and aim "something" at the moon: Even a single 13 dB Yagi and 100W can be enough to work other stations who are a bit better equipped. That was almost never possible before WSJT coding was developed.
However, in doing that you probably won't hear your own reflection, and operating JT-65 still takes some skill as well as reasonably good weak signal equipment (very stable, very accurate, very sensitive, SSB-CW gear).
Normally dish antennas aren't employed even for e.m.e. on any band below 70cm, and not that many moonbouncers use dishes even there. They're more commonly employed where reasonably sized ones can have a lot of gain, like 2.3 GHz and above.
Stacked yagis, quads, quagis and loop yagis are far more common at 1.2 GHz and below.
Moonbounce antennas are very rarely installed where they cannot be reached, such as on a tall tower. No need to put them up there, and if they're out of reach they're much more of a pain to adjust, optimize, etc.
WB2WIK/6
I assume if you have the antennas down on the ground you want them as far away from ground clutter (trees, buildings power lines) as possible? I was reading up on the 2 meter 440 EME that amateurs were doing back in the mid 70s, seemed like it would be interesting to try. They were mostly discussing dish antennas as the means for doing EME, the dish they were using for 2 meter or 440 MHz was around 30 feet in diameter with a duplexer at the array focal point. Looked like everything would have to be locked in tight or you wouldn't get good reception or a good signal out. I take it SSB and CW are the best modes for EME? Because they were talking about EME FM simplex with 2 meters and 440. I know it wasn't satellite operation, because they only had the duplexer so they could switch bands if there was no contacts made on one or the other. And, it appeared from the picture that the dish was stationary, which didn't make sense to me as the moon is always moving. I figured they would have to track it across the sky to keep a good solid signal. But, the picture was not the best quality so there might have been some mechanism to move its position, I just couldn't see it. I'm gonna guess using FM they would need a lot more power than if they used SSB phone or CW for the the contacts? I have always been interested in satellite and EME and just now starting to get the funds together to try it. Might be awhile before I am set up, but I want to make sure I do everything properly. I hate getting frustrated and wanting to bend yagi elements, just kidding.
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Obi-wan "You were the chosen one. It was said you'd destroy the Sith, not join them. Bring balance to the Force, not leave it in darkness."
I assume if you have the antennas down on the ground you want them as far away from ground clutter (trees, buildings power lines) as possible?
Sure, but you can operate e.m.e. successfully with all sorts of ground clutter, since the best paths are elevated above the horizon, so you'd normally be aimed over all that stuff.
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I was reading up on the 2 meter 440 EME that amateurs were doing back in the mid 70s, seemed like it would be interesting to try. They were mostly discussing dish antennas as the means for doing EME, the dish they were using for 2 meter or 440 MHz was around 30 feet in diameter with a duplexer at the array focal point.
That wouldn't be a duplexer. But anyway, in the 60s most of the moonbouncers (and there weren't many) were "big gun" stations who were really serious and often operated from commercial sites with huge dishes. It takes an enormous dish to have substantial gain at 144 MHz, much larger than 99.9% of anybody sane would install at their home. Virtually all of the "big gun" 2m moonbouncers today use yagi arrays.
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Looked like everything would have to be locked in tight or you wouldn't get good reception or a good signal out. I take it SSB and CW are the best modes for EME?
No, JT-65 is the best mode for e.m.e. However CW is still used quite a bit. SSB is almost never used, it occupies too much bandwidth and makes signals too weak. But you need a high quality SSB transmitter to run JT-65.
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Because they were talking about EME FM simplex with 2 meters and 440. I know it wasn't satellite operation, because they only had the duplexer so they could switch bands if there was no contacts made on one or the other. And, it appeared from the picture that the dish was stationary, which didn't make sense to me as the moon is always moving. I figured they would have to track it across the sky to keep a good solid signal. But, the picture was not the best quality so there might have been some mechanism to move its position, I just couldn't see it. I'm gonna guess using FM they would need a lot more power than if they used SSB phone or CW for the the contacts? I have always been interested in satellite and EME and just now starting to get the funds together to try it. Might be awhile before I am set up, but I want to make sure I do everything properly. I hate getting frustrated and wanting to bend yagi elements, just kidding.
I don't think a single amateur contact has ever been made via moonbounce using FM as a mode. It would take unbelievable e.r.p. Maybe it could be done using a vastly oversized commercial dish, beyond the scope of anything hams would have. But I've never heard of anyone doing it. CW was used for almost all moonbounce contacts for decades, but now that WSJT digital modes are available (and the software is free!), JT-65 is becoming popular.
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Either file a petition with the FCC for your pet QRZ tirade, or have a steaming cup of "Shut The Hell Up!"
"He's dead, Jim. You take his Tricorder and I'll get his wallet."
"The problem with America is stupidity. I'm not saying there should be a capital punishment for stupidity, but why don't we just take the safety labels off of everything and let the problem solve itself?"
That looks hot, but I don't think the Mrs. would let me get away with it. The thought of the tower I have sitting in the garage going up soon has ruffled her "I want a white picket fence home" feathers. For some reason she notices the G5RV that goes from the backyard tree to the front yard tree, yet no one else that stops by notices it until I point it out. It goes like this "Is there anyway you can move that ladder looking thing hanging from the trees?" LOL. And, she gets irritated when I talk loud using SSB. But, I love her and she is usually pretty understanding with amateur radio except at 3 or 4 am in the morning. Plus she doesn't enjoy listening to CW like I do, can't understand why.
I assume though there are less substantial EME set ups than that thing?
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Obi-wan "You were the chosen one. It was said you'd destroy the Sith, not join them. Bring balance to the Force, not leave it in darkness."
We appreciate your support.
What is the best setup for EME?
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Linear Mode
