Author Topic: EME: Earth Moon Earth Communications  (Read 30833 times)

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Offline Electro Fan

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EME: Earth Moon Earth Communications
« on: May 25, 2015, 11:38:48 pm »
Thanks to the ever stimulating EEV forum, I happened across a thread that was started by Bidski on LNAs which included this post by VK5RC:

https://www.eevblog.com/forum/beginners/100mhz-lna/msg679432/#msg679432

In the post VK5RC mentioned that he has been building an EME (Earth Moon Earth) communications system.  The concept is certainly understandable and believable technologically but the notion that the knowledge, skill, and wherewithal exists for an individual to build such a system seems very impressive, if not astonishing; apparently it is a doable challenge.  My guess is that it's beyond my abilities but I thought it would be worth some research to learn what's involved.  I figured maybe some others might find this interesting...

In doing some reading I found this excellent article:

http://www.k4lrg.org/Projects/K4MSG_EME/

Looks like it requires a transmitter, maybe 100 watts or less?
- Might need a license?

Needs a receiver that can pick out a signal about 24 dB below the noise floor?
- Kind of an exciting challenge by itself

But what really caught my attention is the graph showing the monthly distance (between Earth and Moon) and signal degradation.  Checkout the big spike - what's that?  Noise from the Sun?  Nope.

"The smaller degradation peak occurs when the Moon is roughly coincident with the Sun, while the very large peak occurs when the Moon is passing in front of the Milky Way, a *HUGE* source of galactic noise!"  Wow!  (I suppose every astronomer knows this but I found it impressive to see the extent to which "Galactic Noise" is present, revealed, and quantified on the graph.)

Ok, that's all I know so far but if anyone wants to discuss how practical or difficult an EME project might be, please feel free to chime in.  Perhaps VK5RC and others who have experience can provide some guidance.  Don't know if K4MSG (author of the article linked above) visits the EEV forum but maybe he would be up for advising as well.

EF
« Last Edit: May 25, 2015, 11:47:38 pm by Electro Fan »
 

Offline mackrc1

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Re: EME: Earth Moon Earth Communications
« Reply #1 on: May 26, 2015, 12:19:03 am »
EME is certainly a very interesting sector of ham radio and is well documented as well. You don't need to be an expert to to do it but it can be challenging to get it right.
You will definitely need a license. I always advise people to stick to the law and get a license, but for screwing around with a watt or two you really needn't bother. However EME is very difficult to do on low power so get a license first if you plan to do this.
An LNA at 100mhz seems to me rather pointless and a waste of effort (Not to discourage though its always fun to try!). Loss at this frequency isn't a huge issue and you will be better off focussing on your antenna. I'm going off my guts here I'm not an expert in EME but I can't see it be a necessity.
If you are wanting to get into this, start off by listening into stations. Get yourself a decent SDR radio (lots of fun to be had with these thing) and build yourself a basic EME station. Once you've become an expert in receiving go get a license and and a radio (or build one!) and start trying to communicate! Hopefully by this time you will have discovered all the other opportunities available in amateur radio!
Just my thoughts  ;)
« Last Edit: May 26, 2015, 12:21:10 am by mackrc1 »
 

Offline Dragon88

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Re: EME: Earth Moon Earth Communications
« Reply #2 on: May 26, 2015, 01:06:05 am »
Yup, this is a documented (if less common) aspect of ham radio. Get a license and you can experiment to your heart's content using the ham bands.

Also look up meteor burst communication. Even just monitoring the ISS passing overhead can be fun. Astronaut hams sometimes pick up the mic and make QSOs with ground stations as well.
 

Offline Alex Eisenhut

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Re: EME: Earth Moon Earth Communications
« Reply #3 on: May 26, 2015, 01:22:44 am »
Pretty cool, but what's really gonna fry your noodle is that they radared Venus from the Earth to find out its rotation period and plane... in 1961.
Hoarder of 8-bit Commodore relics and 1960s Tektronix 500-series stuff.
 

Offline dave_k

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Re: EME: Earth Moon Earth Communications
« Reply #4 on: May 26, 2015, 02:34:35 am »
An LNA at 100mhz seems to me rather pointless and a waste of effort (Not to discourage though its always fun to try!).

Plus, 100MHz is right in the middle of the FM broadcast band where transmitter power levels approaching +70dBm are not uncommon. Depending where you are that might be a rather annoying source of interference.
 

Offline chickenHeadKnob

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Re: EME: Earth Moon Earth Communications
« Reply #5 on: May 26, 2015, 03:50:49 am »
I am not a ham but I first heard about moonbounce decades ago from a colleague ee/ham. So old news. I also remember seeing a picture of one of the laser  reflectors left by the Apollo  missions (11,14,15). Wiki here:http://en.wikipedia.org/wiki/Lunar_Laser_Ranging_experiment

You don't need a ham license to ping one of those!
 

Offline VK5RC

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Re: EME: Earth Moon Earth Communications
« Reply #6 on: May 26, 2015, 04:57:30 am »
I think the first EME was looked at in late WW2, as a method of ship data comms,  but the crap S/N limits data rate, Shannon limit.
The Ham ticket is not that hard especially if you have a interest in electronics but opens up for experimentation a big chunk of RF spectrum. Local ham clubs are always looking to encourage new hams.
Whoah! Watch where that landed we might need it later.
 

Offline Electro Fan

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Re: EME: Earth Moon Earth Communications
« Reply #7 on: May 26, 2015, 06:45:42 am »
If you are wanting to get into this, start off by listening into stations. Get yourself a decent SDR radio (lots of fun to be had with these thing) and build yourself a basic EME station. Once you've become an expert in receiving go get a license and and a radio (or build one!) and start trying to communicate!

Ok, this seems like a reasonable approach.

Below is the list of items suggested in the article for a transmit/receive EME.  How would you modify it for "Phase 1 Receive Only" while hopefully being able to reuse some/most? of the investment for "Phase 2 Receive and Transmit"?  Thx

1.     TRANSCEIVER: Whatever you choose to spend.
2.     AMP/PREAMP: Up to $450 new depending on brand; less if purchased used.
3.     POWER SUPPLY: Up to $200 for a new linear-type. I paid $105 shipped for a new MFJ switcher (compact, reliable, and there are *NO* noise problems with it!).
4.     ANTENNA: $225-$250 including shipping and/or local sales tax (if bought from HRO).
5.     TV ROTOR: ~$100.
6.     LOW-LOSS COAX: ~$60-$120 depending on type and length.
7.     INTERFACE UNIT: $160 for a Rigblaster Plus II.
8.     PC/LAPTOP: Whatever you choose to spend.
9.     WSJT and Dimension 4 software: FREE
 

Offline TSL

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Re: EME: Earth Moon Earth Communications
« Reply #8 on: May 26, 2015, 07:08:59 am »
You can learn a lot by going to the penultimate Australian EME website of VK3UM...

http://vk3um.com/

Doug has written the excellent program EME calculator, that will allow you to work out the entire path loss/system gain for a two way contact via the moon. Its fun to experiment with different antenna types in it to see what effect it has on the path loss.

He's also written EME Planner, Libration Calculator, and others to assist you in an EME adventure.

Oh and check out the pictures of his 8m dish that's mounted on a Centurion Tank ring gear so he can rotate it!

regards

Tim
« Last Edit: May 26, 2015, 07:11:16 am by TSL »
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Offline Electro Fan

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Re: EME: Earth Moon Earth Communications
« Reply #9 on: May 26, 2015, 07:23:59 am »
I think the first EME was looked at in late WW2, as a method of ship data comms,  but the crap S/N limits data rate, Shannon limit.
The Ham ticket is not that hard especially if you have a interest in electronics but opens up for experimentation a big chunk of RF spectrum. Local ham clubs are always looking to encourage new hams.

VK5RC - I "ported" your other post into this thread so it's all together, Thanks, EF

---

Hi EF,  EME is achievable with home-brew gear,  there are quite a few Hams who have EME capable stations. 
Probably the easier path is to get your ham ticket which will allow you to transmit a reasonable power level on a frequency where someone else is listening. 
Guys  like vk3um ve4ma are some of the leaders in the field.
There appears roughly 2 paths,  first go for morse or voice level communication which needs a lot better S/N ie more power,  better antenna (dish)  and better receive path.  The other path is to use spread spectrum techniques (computer encoding decoding)  using a program eg jt65,  S/N can be as low as - 18dB ie below noise and still get decode.  This allows medium level eg 100w,  modest antennas ie yagis,  and little preamp. Activity on 140MHz JT65  ham band is quite active,  building a receive only station negates licencing issues.  Another area that may interest you is WSPR,  another digital mode. Communicating across the globe with 0.1 W is fascinating.
It is an interesting technical 'hobby'.
Regards Rob
 

Offline Electro Fan

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Re: EME: Earth Moon Earth Communications
« Reply #10 on: May 26, 2015, 07:31:51 am »
Looks like vk3um is a leader in EME.

This is very cool (Sample Echo Off The Moon):
http://www.vk3um.com/1296_CW_Feb06.wav

But I think I'd need to find an antenna that will fly a little better with the Home Owner's Association:
http://www.vk3um.com/Dish%20Photos.html
« Last Edit: May 26, 2015, 07:34:53 am by Electro Fan »
 

Offline G7PSK

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Re: EME: Earth Moon Earth Communications
« Reply #11 on: May 26, 2015, 07:52:45 am »
On VHF you can get good EME with just a Yagi antenae. Many people will use 4 coupled together but one on its own will work. Take a look at this site/PDF.

http://tcf.pages.tcnj.edu/files/2013/12/SMALLSTATIONEME.pdf
 

Offline Nuno_pt

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Re: EME: Earth Moon Earth Communications
« Reply #12 on: May 26, 2015, 08:21:40 am »
You can do EME in any band, most use is 50MHz and up, on 50 till 432MHz you can go for a single yagi, but the most use is 4 yagi's on an H bay, let's say for 50MHz 4x7elements.

If you go for 1.2GHz and up you are better serve with an satellite dish, for making some QSO's the minimum recommended it's 3 meters dish and about 300W on the feed for 1.2GHz.

Just Google for EME station.
« Last Edit: May 26, 2015, 08:25:18 am by Nuno_pt »
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Offline Howardlong

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Re: EME: Earth Moon Earth Communications
« Reply #13 on: May 26, 2015, 09:31:14 am »
A reasonable stepping stone is ham radio satellites. If you can't receive those, you'll have a mighty tough time doing EME.

You don't even need an expensive setup, but the lessons drawn from satellites including orbital prediction, weak signal reception, antenna polarisation and doppler can be applied directly to both satellites and EME.

I've done many live demos at ham fests with just an off the shelf handheld radio and hand held yagi. There is a knack to it as with many facets of this kind of thing, it wouldn't be interesting if there wan't some skill to gain.

You can also pick up telemetry from LEOs with just a simple monopole antenna, an SDR and a PC.

Finally, I should warn you about EME. I was lucky enough to be invited to be the after-dinner guest speaker at the annual worldwide EME conference when it was held in Cambridge, UK in 2012. There were a lot of folks there from across the globe, a couple of hundred or so, a lot of whom are pretty seriously into this stuff. If thought collecting exotic test equipment was a reasonably hedonistic way to spend your kids' inheritance, you should see what some of these guys get up to!
 

Offline VK5RC

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Re: EME: Earth Moon Earth Communications
« Reply #14 on: May 26, 2015, 11:24:09 am »
+1 re HowardLong's comments, but it is a lot of fun and you can do it more cheaply than K4MSG lists but it is a good article. EF Thanks for porting my comments!
I have found Amateur radio a lot of fun as there are different areas you can get an interest in, they do vary after a few years. Also there are a lot of good guys like W2AEW keen and good teachers.
I have posted some photos of parts of my setup. For me this is a hobby and EME has taken me about 18months of my infrequent spare time (job and family) and saving for bits and pieces
Firstly the feed horn, it is an VE4MA super, consisting of 7" stainless steel gas flue pipe and a 16" diameter cake tin ! The G4DDK LNA can be seen, the receive relay is hidden behind. Red is the transmit line, green is receive.
Secondly is the PA, I think it is getting out about 300W at 1296HMz, I bought two of W6PQLs pre made PA s - you can see one standing vertically closest to the camera (not cheap but nice units). You need to split the signal before and then recombine after,  see the Hybrid couplers and plumbing on the top surface. It sucks some juice needing 25A at 28V. No magic smoke released yet but no self echo either!
« Last Edit: May 26, 2015, 11:37:47 am by VK5RC »
Whoah! Watch where that landed we might need it later.
 

Offline w2aew

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Re: EME: Earth Moon Earth Communications
« Reply #15 on: May 26, 2015, 02:36:35 pm »
I think the first EME was looked at in late WW2, as a method of ship data comms,  but the crap S/N limits data rate, Shannon limit.
The Ham ticket is not that hard especially if you have a interest in electronics but opens up for experimentation a big chunk of RF spectrum. Local ham clubs are always looking to encourage new hams.

Just a bit of history - EME was first accomplished in 1946 - a US Army Signal Corp experimental project called Project Diana:
http://en.wikipedia.org/wiki/Project_Diana
It actually paved the way for radio astronomy and even manned space-flight, long range space exploration, etc. (up until then, no one knew of radio signals could penetrate our atmosphere).  This project was run out of Camp Evans, part of Fort Monmouth in NJ (less than an hour from my home).  The site is now part of a historical site.  One of the amateur radio clubs I belong too has their facility in the same building that Diana was operated in.  The mounts for the radar antenna that was used are still in the ground outside of the building.  Cool stuff!
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Offline Electro Fan

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Re: EME: Earth Moon Earth Communications
« Reply #16 on: May 26, 2015, 06:54:33 pm »
Thanks very much to everyone for the info, enthusiasm, and encouragement.

I'm trying to figure out if EME is feasible given my current state of knowledge and abilities.  To figure it out I've made a small initial project outline.  Please feel free to insert any answers, info, comments, questions, etc.  Thanks!

EME Project

Phase 0 (Feasibility Assessment)

Phase 1 (Receive Only)
•   Phase 1A:  Receive a terrestrial HAM signal
•   Phase 1B:  Receive a LEO signal
•   Phase 1C:  Receive something tougher than a LEO signal but easier than an EME signal?  Any need for this step?
•   Phase 1D:  Receive an EME signal

Phase 2 (Transmit and Receive)
•   Phase 2A:  Transmit and receive terrestrial HAM signal
•   Phase 2B:  Transmit and receive a LEO signal
•   Phase 2C:  Transmit and receive something in between LEO and EME signal?  Any need for this step?
•   Phase 2D:  Transmit and receive an EME signal

Questions (for Phase 0 Feasibility Assessment)

Questions Regarding Phase 1
1.   Can the same transceiver and antenna (in receive only mode) be used for Phase 1A and Phase 1B?  For example, is it fair to assume that Phase 1A and 1B could both be done with a Yaesu FT-60R (or lesser radio) and a handheld or small tripod mounted antenna?

2.   Is there a need for Phase 1C?  If so, what is it?

3.   What is the lowest cost and/or fastest path to Phase 1D?  (What is the recommended configuration for Phase 1D?  How much if anything used in Phase 1A and 1B can be reused?)  Does it make sense to build a configuration suitable for Phase 1D and use it for Phase 1A and 1B?

4.   Key Question:  Is it correct that all of Phase 1 can be done (in the U.S.) without a FCC license?

Questions Regarding Phase 2
1.   Key Question:  What license(s) will be needed for Phase 2?
?   Phase 2A:  Technician?
?   Phase 2B:  General?
?   Phase 2D:  ?

2.   What is the recommended incremental configuration for progressing from 2A thru 2D?  ie, How much if anything used in Phase 2A and 2B can be reused in 2D?  Key Question:  What is the smallest antenna that is likely to achieve a successful transmission in Phase 2D?  (The neighborhood isn't likely to support anything much more than a portable/temporary tripod mounted antenna; possibly a DirecTV size dish, but nothing larger will fly around here.)

3.   In Phase 2A it would seem possible to send and receive my own signal.  Can sending and receiving my own signal be done in Phase 2B and 2D, or is the nature of LEO and EME Transmit/Receive such that it is unlikely to receive your own signal?  (ie, Are LEO and EME transmissions largely or entirely dependent on someone else confirming receipt of a LEO or EME transmission via a QSO?)
« Last Edit: May 26, 2015, 06:56:43 pm by Electro Fan »
 

Offline Nuno_pt

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Re: EME: Earth Moon Earth Communications
« Reply #17 on: May 26, 2015, 08:04:57 pm »
First thing first, what band do you plan to do EME, 50, 144, 432MHz, 1.2, 2.4, 5.7, 10GHz?

Then go from here.
Nuno
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Offline AG6QR

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Re: EME: Earth Moon Earth Communications
« Reply #18 on: May 26, 2015, 09:38:35 pm »
I'm a licensed ham, but haven't done EME (but have read some about it), so I'll try to limit my answers to those areas where I have some knowledge.

First, getting a license isn't very hard.  If you're reading this board, you probably have most of the electronic theory background already, and that's what most candidates find the toughest part.  Since you've said you're in the US, I'll go out on a limb here and say that getting a license is the easiest and cheapest part of the journey you're planning (other country's license requirements may be harder).  But getting a license does require taking an exam, and taking an exam requires finding a site and time where an exam is offered.  After the exam, it will take a few weeks for the paperwork to be processed.  So try to get that out of the way ASAP.  Go to http://www.arrl.org/getting-licensed and poke around to find out more info.  It would be a shame to get to Phase 1D, then start looking for an exam session, and find out that you were a week late for an exam session, and the next one in your area was several months away.

Practice exams are available on-line from various sites.  Take a few until you are solidly passing.

Quote
Key Question:  What license(s) will be needed for Phase 2?

Most EME work is done in the VHF/UHF bands, where a technician has full privileges.  So the most basic license will do the trick.  However, once you're in an exam session, you can take as many tests as you want for the one fee you paid, until you fail an exam or pass them all.  So you might as well try for the general and extra exams while you're there.  These license classes open up lots of opportunities on the HF (shortwave) bands, where you can bounce signals off the ionosphere and talk around the world.  It's a different niche of Ham radio, but an interesting and popular one.

Quote
is it fair to assume that Phase 1A and 1B could both be done with a Yaesu FT-60R (or lesser radio) and a handheld or small tripod mounted antenna?

Phase 1A/1B, and 2A/2B, yes.  But it's probably a dead end as far as EME.

The FT-60R is a nice radio, I've got two myself.  But it is a low powered FM-only walkie-talkie.  Plenty of people use them for satellite communications, with upgraded antennas.  You can even talk to the astronauts aboard the ISS, if your timing is just right and you have a bit of luck.  But a problem is that it won't send or receive the modes most useful for weak signal work.  My understanding is that most EME is done with SSB, Morse, or various digital modes, and an FM-only radio won't do any of that.  Someone has probably done EME using FM, but it would require significantly more antenna and power than the other modes.  I believe what you want is an all-mode transceiver that covers the bands you're interested in.  There are various possibilities here, but I don't know enough to recommend specific makes/models.

There are hams who thrive on a challenge and like to do something most people would call impossible.  You could probably get a nice writeup in QST (the ARRL's monthly magazine) if you managed to make an EME contact using an FT-60R.  The antenna and amplifier required to accomplish such a feat would not be trivial or inexpensive.

Quote
Key Question:  Is it correct that all of Phase 1 can be done (in the U.S.) without a FCC license?

Yes, there is no license required for receiving, period.  Furthermore, it is legal to own transmitters without holding a license, but it is not legal to transmit with them.  So, at least in theory, you could buy a transceiver that you would eventually use for phase 2, even before you got your license.  Some sellers might not be eager to sell to you before you were licensed, however.

Quote
In Phase 2A it would seem possible to send and receive my own signal.  Can sending and receiving my own signal be done in Phase 2B and 2D, or is the nature of LEO and EME Transmit/Receive such that it is unlikely to receive your own signal?

For EME, you are likely to receive your own signal, like it or not.  There's a bit more than a 2 second delay for EME round-trip.  That's plenty of time for a transceiver to switch from transmit to receive and to begin receiving.
« Last Edit: May 26, 2015, 10:00:12 pm by AG6QR »
 

Offline eneuro

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Re: EME: Earth Moon Earth Communications
« Reply #19 on: May 26, 2015, 11:02:04 pm »
The mounts for the radar antenna that was used are still in the ground outside of the building.  Cool stuff!
Even in this ARRL Amateur Radio Technician Class Training Course they mentioned EME communication at UHF/VHF and said something about Yagi antenas and... parabolic dishes.

Why parabolic dish is in my interest-that is simple-during the day use it for solar thermal in CSP, but at night if it could be used for radio communication it could be even more fun, so trying to estimate if 3m-5m parabolic dish could be usable for EME?  :popcorn:
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Offline VK5RC

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Re: EME: Earth Moon Earth Communications
« Reply #20 on: May 26, 2015, 11:51:44 pm »
The problem of dual use parabolic dishes is in swapping the hardware out of the focal point,  not an insoluble problem though.  The dish surface obviously needs to be both rf and light reflective. When you solve it,  post your solution.  I'd be interested!
Interesting history re eme,  my memory was a bit off!
Whoah! Watch where that landed we might need it later.
 

Offline Electro Fan

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Re: EME: Earth Moon Earth Communications
« Reply #21 on: May 27, 2015, 02:16:00 am »
First thing first, what band do you plan to do EME, 50, 144, 432MHz, 1.2, 2.4, 5.7, 10GHz?

Then go from here.

That's a fair question but I don't have enough experience to know.  My objectives are to make it as easy/practical and cost-effective as possible to bounce a signal off the Moon and hear it come back to Earth.  My biggest constraint is that I can't deploy a big antenna.  Perhaps some type of small to medium size Yagi will have to do, but no dish is likely to be doable.

Next, as I don't have a license yet, I'd like to go for whatever will minimize licensing (ie, the lesser the license requirement the better).

Other than those considerations, I'm open to whatever frequency (or frequency tradeoffs) you suggest.
 

Offline retrolefty

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Re: EME: Earth Moon Earth Communications
« Reply #22 on: May 27, 2015, 02:31:39 am »
Been a ham for decades but not very active and never did any EME but read a lot and visited a few 'shacks' that were set up for EME. First know that EME can be a real time and cash sink. You have to figure out what total budget you want to invest then put 50% into the antenna/rotator/low loss feedline and the rest goes into good low noise preamp and then either a transceiver or separate receiver/transmitter. Good challenge and as I said there is a ton of ham reading material available. The best path is if you can find a local 'Elmer' that has first hand experiance to mentor your path. Good luck

EDIT: Getting a U.S ham licence is easier then ever. They dropped all morse code testing requirement and there are on-line practice testing sites for all licence levels. I went from a Technician to Extra class with just a couple of weeks with the practice sessions and then one trip to a local testing session one Saturday.



73
« Last Edit: May 27, 2015, 02:35:38 am by retrolefty »
 

Offline w2aew

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Re: EME: Earth Moon Earth Communications
« Reply #23 on: May 27, 2015, 02:39:04 am »
First thing first, what band do you plan to do EME, 50, 144, 432MHz, 1.2, 2.4, 5.7, 10GHz?

Then go from here.

That's a fair question but I don't have enough experience to know.  My objectives are to make it as easy/practical and cost-effective as possible to bounce a signal off the Moon and hear it come back to Earth.  My biggest constraint is that I can't deploy a big antenna.  Perhaps some type of small to medium size Yagi will have to do, but no dish is likely to be doable.

Next, as I don't have a license yet, I'd like to go for whatever will minimize licensing (ie, the lesser the license requirement the better).

Other than those considerations, I'm open to whatever frequency (or frequency tradeoffs) you suggest.

As you may have surmized, there are a LOT of tradeoffs.  Antenna size scales inversely with operating frequency.  Path loss depends highly (and non-linearly) on operating frequency.  etc. etc.

There are quite a few EME enthusiasts in the amateur radio community.  I know a few guys that are really into EME, and most are operating at 432MHz or above.

If you would like to learn more, you might want to view some of these example pages that I found with a simple search:

Moonbouncers Information website: http://www.moonbouncers.org/
EME Newletter archives by K2UYH: http://www.k2uyh.com/news.htm
The 144MHz EME Newsletter: http://www.df2zc.de/newsletter/
Info on mostly 6m EME operation: http://www.bigskyspaces.com/w7gj/


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Offline Electro Fan

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Re: EME: Earth Moon Earth Communications
« Reply #24 on: May 27, 2015, 02:42:25 am »
AG6QR - Thanks.

I'm up for taking the test and I'm pretty sure with some study I can pass the first one, not sure yet about the second.  What I'm not clear about is whether the first license ("Technician") is going to enable me to transmit with the required frequency and power configuration (all still TBD) for the full EME transmit receive project. 

It seems from the reading I've done so far that some sort of digital transmission might have a better chance of succeeding - I'm still very early in figuring out this stuff. 

As mentioned, I'm limited by the size of antenna I can deploy - I'm in a neighborhood where small and unobtrusive is kind of a requirement.  So, maybe I need to work backward from what antenna will be politically acceptable around here.  From there I can figure out what that leaves in terms of transmit/receive frequencies, and how much power is needed from the PA and what sort of LNA will work, and maybe from there what sort of modulation.  Kind of a goofy set of constraints driven by Home Owners Association considerations but it is what it is (the neighbors are very nice, they're just not into big antennas).... so maybe something among SSB, Morse, or something digital.

If the FT-60R stands no chance of doing EME I might be able to go for a mobile/portable or desktop type transceiver that will ultimately power Phase 2D but use it for Phase 1 (receive only) as you suggest.

I'm pretty sure the delay from Earth to Moon and back has to be at least a couple seconds.  In standard Geosynchronous satellite communications the delay up to a satellite and back down is about 270 milliseconds and GeoSats are only about a tenth of the way to the Moon.  Even so with a 2-3 second delay it would seem tricky to be continuously transmitting on one frequency and then trying to tune to another frequency to catch an iffy transmission.   Maybe this would require one transceiver or transmitter for send and another transceiver or receiver for monitoring/receiving?
 


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