Re: European Lunar Lander - Call for Declarations
Keep in mind that any ham radio transponder on the moon will not be an "easy sat". You will need an EME class station to work it.
If we build a lunar transponder, we can expect to see many, many postings on Amsat-BB about how Amsat only cares about elite hams and is not interested in building satellites for the common ham.
I'm not saying it wouldn't be fun to have a transponder on the moon, and we in the USA might even be able to help you build it if they get ITAR fixed in time, but we better put on the flame proof trousers when we announce the project to the masses.
Dan Schultz N8FGV
Thanks Dan,
Point well taken. Now, keep in mind we can find 1001 reasons why not. On the other hand, how about reasons to do it? How many times will we ever get a "free" ride to the moon surface? At this stage we need to declare our interest and yes ITAR is a potential problem. However, how about we support AMSAT-DL (in case they go for it) or AMSAT-UK or AMSAT-IT. Encourage them to move on this. There are means and ways (for the US) to work with others without being limited by ITAR. It is just too bad that so many times we seem to focus on the difficulties and loose sight of the opportunities.
Thanks again, appreciate your feedback.
Stefan VE4NSA
On Fri, Jun 1, 2012 at 6:54 PM, Daniel Schultz [email protected] wrote:
Keep in mind that any ham radio transponder on the moon will not be an "easy sat". You will need an EME class station to work it.
If we build a lunar transponder, we can expect to see many, many postings on Amsat-BB about how Amsat only cares about elite hams and is not interested in building satellites for the common ham.
I'm not saying it wouldn't be fun to have a transponder on the moon, and we in the USA might even be able to help you build it if they get ITAR fixed in time, but we better put on the flame proof trousers when we announce the project to the masses.
Dan Schultz N8FGV
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
I disagree about having to have a EME class station if we put a transponder on the moon. The reason being, since the same side is always facing the earth, a directional high gain antenna may be used on the transponder itself!
Lee W5LMM
On 06/01/12 19:54, Daniel Schultz wrote:
Keep in mind that any ham radio transponder on the moon will not be an "easy sat". You will need an EME class station to work it.
If we build a lunar transponder, we can expect to see many, many postings on Amsat-BB about how Amsat only cares about elite hams and is not interested in building satellites for the common ham.
I'm not saying it wouldn't be fun to have a transponder on the moon, and we in the USA might even be able to help you build it if they get ITAR fixed in time, but we better put on the flame proof trousers when we announce the project to the masses.
Dan Schultz N8FGV
Are you sure about that, Dan? I'm hardly an expert on EME, still looking to get there, but based on numbers I worked with some time ago, even 500mW from the Moon should be copyable with a good radio, with a yagi and possibly a preamp. This is not to say that a random HT would work, but I don't think we're talking of the classic EME-capabile station.
--STeve Andre' wb8wsf en72
Just for the "fun" of it I'd like to see an accurate link budget written up. It is a little bit out of my comfort zone. Maybe Domenico or one of you who has this knowledge could do it. I may even learn something.
73 Bob W7LRD
antennas still down
----- Original Message -----
From: "STeve Andre'" [email protected] To: [email protected] Sent: Friday, June 1, 2012 9:20:35 PM Subject: [amsat-bb] Re: European Lunar Lander - Call for Declarations
On 06/01/12 19:54, Daniel Schultz wrote:
Keep in mind that any ham radio transponder on the moon will not be an "easy sat". You will need an EME class station to work it.
If we build a lunar transponder, we can expect to see many, many postings on Amsat-BB about how Amsat only cares about elite hams and is not interested in building satellites for the common ham.
I'm not saying it wouldn't be fun to have a transponder on the moon, and we in the USA might even be able to help you build it if they get ITAR fixed in time, but we better put on the flame proof trousers when we announce the project to the masses.
Dan Schultz N8FGV
Are you sure about that, Dan? I'm hardly an expert on EME, still looking to get there, but based on numbers I worked with some time ago, even 500mW from the Moon should be copyable with a good radio, with a yagi and possibly a preamp. This is not to say that a random HT would work, but I don't think we're talking of the classic EME-capabile station.
--STeve Andre' wb8wsf en72
_______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
I disagree about having to have a EME class station if we put a transponder on the moon. The reason being, since the same side is always facing the earth, a directional high gain antenna may be used on the transponder itself!
Lee W5LMM
How big antenna and what band should be used? Please calculate the best combination here:
http://www.changpuak.ch/electronics/calc_10.php
Note that you need about -120dBm signal to be heard in receiver. The path is about 400000km (240000 miles).
-jari oh3uw ;-)
Check http://www.amsatuk.me.uk/iaru/spreadsheet.htm for a detailed link budget spreadsheet, with accompanying explanations.
73, art….. W4ART Arlington VA
On 2-Jun-2012, at 01:16 AM, Bob- W7LRD wrote:
Just for the "fun" of it I'd like to see an accurate link budget written up. It is a little bit out of my comfort zone. Maybe Domenico or one of you who has this knowledge could do it. I may even learn something.
73 Bob W7LRD
antennas still down
Please contribute: http://pages.teamintraining.org/nca/moabtour12/afeller
Check also this discussion from James Miller, G3RUH:
http://www.amsat.org/amsat/articles/g3ruh/110.html
73s Peter, DB2OS
Hi together,
Please also have a look at this document: http://wsn.spaceflight.esa.int/docs/lunarlander/LunarLander_EIDA_CDI_230512....
in particular see point 2.2.2 Communication and 2.2.3:
"Visibility of the Earth from the landing site imposes the following constraint: • communications shall only be possible within a 13.7 day (TBC) window each month, and shall depend on the availability of the ground station."
further:
"the mean power available for an individual payload is expected not to exceed 20W"
73s Peter DB2OS
On 03.06.2012 00:29, Peter Guelzow wrote:
Check also this discussion from James Miller, G3RUH:
http://www.amsat.org/amsat/articles/g3ruh/110.html73s Peter, DB2OS
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
That can't be quite right. A gain antenna can be put on the moon but its half power beam width will be limited by libration. If we put a 2.401 GHz dish on the thing we could easily stay inside the HPBW and likely not need much power for a decent signal into a small dish on the earth.
The problem is what to do with the things in the dark when it is truly cold and similarly hot when in the sun.
I suggest no battery and nearly as dumb as a rock linear transponder. It probably isn't an earth satellite so it doesn't need much in the way of control.
Interesting to say the least.
Bob On Jun 1, 2012 8:05 PM, "Daniel Schultz" [email protected] wrote:
Keep in mind that any ham radio transponder on the moon will not be an "easy sat". You will need an EME class station to work it.
If we build a lunar transponder, we can expect to see many, many postings on Amsat-BB about how Amsat only cares about elite hams and is not interested in building satellites for the common ham.
I'm not saying it wouldn't be fun to have a transponder on the moon, and we in the USA might even be able to help you build it if they get ITAR fixed in time, but we better put on the flame proof trousers when we announce the project to the masses.
Dan Schultz N8FGV
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Hi Peter, DB2OS
I was reading the document in particular point 2.2.2 Communication and 2.2.3 but in my opinion the Radio Hams are off side because everyting has been already designed and in my opinion there is no room available on the Lander for a Moon-Earth experimental communication transponder in our L band and S band because our antennas are too big.
Since the main 7.2 and 8.5 GHz X band High Gain Antennas of the Lander are oriented toward the Earth in a fixed position to compensate the pointing for libration probably only a 5 watt pep and a circularly polarized horn on our 10.5 GHz should be possible.
73" de
i8CVS Domenico
----- Original Message ----- From: "Peter Guelzow" [email protected] To: [email protected] Sent: Sunday, June 03, 2012 12:57 AM Subject: [amsat-bb] Re: European Lunar Lander - Call for Declarations
Hi together,
Please also have a look at this document:
http://wsn.spaceflight.esa.int/docs/lunarlander/LunarLander_EIDA_CDI_230512. pdf
in particular see point 2.2.2 Communication and 2.2.3:
"Visibility of the Earth from the landing site imposes the following constraint: • communications shall only be possible within a 13.7 day (TBC) window each month, and shall depend on the availability of the ground station."
further:
"the mean power available for an individual payload is expected not to exceed 20W"
73s Peter DB2OS
On 03.06.2012 00:29, Peter Guelzow wrote:
Check also this discussion from James Miller, G3RUH:
http://www.amsat.org/amsat/articles/g3ruh/110.html73s Peter, DB2OS
Thanks folks,
That's a very helpful and constructive discussion. It will certainly allow for better assessment of the feasibility, options and limitations.
Stefan, VE4NSA
On Sat, Jun 2, 2012 at 8:54 PM, i8cvs [email protected] wrote:
Hi Peter, DB2OS
I was reading the document in particular point 2.2.2 Communication and 2.2.3 but in my opinion the Radio Hams are off side because everyting has been already designed and in my opinion there is no room available on the Lander for a Moon-Earth experimental communication transponder in our L band and S band because our antennas are too big.
Since the main 7.2 and 8.5 GHz X band High Gain Antennas of the Lander are oriented toward the Earth in a fixed position to compensate the pointing for libration probably only a 5 watt pep and a circularly polarized horn on our 10.5 GHz should be possible.
73" de
i8CVS Domenico
----- Original Message ----- From: "Peter Guelzow" [email protected] To: [email protected] Sent: Sunday, June 03, 2012 12:57 AM Subject: [amsat-bb] Re: European Lunar Lander - Call for Declarations
Hi together,
Please also have a look at this document:
http://wsn.spaceflight.esa.int/docs/lunarlander/LunarLander_EIDA_CDI_230512. pdf
in particular see point 2.2.2 Communication and 2.2.3:
"Visibility of the Earth from the landing site imposes the following constraint: • communications shall only be possible within a 13.7 day (TBC) window each month, and shall depend on the availability of the ground station."
further:
"the mean power available for an individual payload is expected not to exceed 20W"
73s Peter DB2OS
On 03.06.2012 00:29, Peter Guelzow wrote:
Check also this discussion from James Miller, G3RUH:
http://www.amsat.org/amsat/articles/g3ruh/110.html73s Peter, DB2OS
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Hi Stefan VE4NSA, Peter DB2OS and folks on BB
It should be very nice to have a transponder on the Lunar Lander operating into the X/K band 10,5 GHz Uplink and 24 GHz downlink. As on AO40 the antennas are very small and probably there is room for a transponder.
For a good feasibility and assesment with ESA it would be very important to have also a 24 GHz Beacon relaying to us TLM data concerning some primary ESA experiments.
Just my idea.
73" de
i8CVS Domenico ----- Original Message ----- From: Stefan Wagener To: i8cvs Cc: Peter Guelzow ; Amsat - BBs Sent: Monday, June 04, 2012 9:26 AM Subject: Re: [amsat-bb] Re: European Lunar Lander - Call for Declarations
Thanks folks,
That's a very helpful and constructive discussion. It will certainly allow for better assessment of the feasibility, options and limitations.
Stefan, VE4NSA
On Sat, Jun 2, 2012 at 8:54 PM, i8cvs [email protected] wrote:
Hi Peter, DB2OS
I was reading the document in particular point 2.2.2 Communication and 2.2.3 but in my opinion the Radio Hams are off side because everyting has been already designed and in my opinion there is no room available on the Lander for a Moon-Earth experimental communication transponder in our L band and S band because our antennas are too big.
Since the main 7.2 and 8.5 GHz X band High Gain Antennas of the Lander are oriented toward the Earth in a fixed position to compensate the pointing for libration probably only a 5 watt pep and a circularly polarized horn on our 10.5 GHz should be possible.
73" de
i8CVS Domenico
----- Original Message ----- From: "Peter Guelzow" [email protected] To: [email protected] Sent: Sunday, June 03, 2012 12:57 AM Subject: [amsat-bb] Re: European Lunar Lander - Call for Declarations
Hi together,
Please also have a look at this document:
http://wsn.spaceflight.esa.int/docs/lunarlander/LunarLander_EIDA_CDI_230512. pdf
in particular see point 2.2.2 Communication and 2.2.3:
"Visibility of the Earth from the landing site imposes the following constraint: • communications shall only be possible within a 13.7 day (TBC) window each month, and shall depend on the availability of the ground station."
further:
"the mean power available for an individual payload is expected not to exceed 20W"
73s Peter DB2OS
On 03.06.2012 00:29, Peter Guelzow wrote:
> Check also this discussion from James Miller, G3RUH: > > http://www.amsat.org/amsat/articles/g3ruh/110.html > > > 73s Peter, DB2OS
_______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Hi all
There is nothing much to do with 20W mean power. Just a 5W pep beacon...
-jari oh3uw
Hi Stefan VE4NSA, Peter DB2OS and folks on BB
It should be very nice to have a transponder on the Lunar Lander operating into the X/K band 10,5 GHz Uplink and 24 GHz downlink. As on AO40 the antennas are very small and probably there is room for a transponder.
For a good feasibility and assesment with ESA it would be very important to have also a 24 GHz Beacon relaying to us TLM data concerning some primary ESA experiments.
Just my idea.
73" de
i8CVS Domenico
participants (10)
-
Bob- W7LRD -
Daniel Schultz -
i8cvs -
Jari Koivurinne -
Lee Maisel -
Peter Guelzow -
Robert McGwier -
Stefan Wagener -
STeve Andre' -
W4ART Arthur Feller