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I was wondering if i could use my gps to locate satellites for fta receiver reception and setting up of satellite dish.

Wow, that's a new one.

Umm, no. A GPS receiver can only receive signals from GPS satellites. And even at that, even though some GPS receivers have a screen that shows the general location of the GPS satellites relative to your location, you can't "locate" the satellites specifically.

Like MM have said, you can't locate the satellites using the GPS. Just like you can't locate a radio station's antenna using your car's radio.

However, you shouldn't have any problems while setting up the dish. Usually, they will include a chart showing the general compass direction of the satellite depending on where you live. They may also include a little gadget with a little light on it. You connect this gadget to the dish's coax connections, and just point the dish in the general direction of the satellite. When you are on target, the little light will light up. That's it.

Now if you can't locate GPS satellites specifically then how could the system work, it wouldn't would it? Of course you can locate GPS satellites.

Locating other satellites? No!

you mean there is not just one giant satellite up there that does everything?

I don't agree. You can not locate any of the GPS satellites. You can not get a 3D position of any of the satellies. You can only get the signals from these satellites. based on the signals, you can calculate where you are located.

As you should realize GPS uses ECXYZ (call these 3D or not if you like) and if your receiver can not determine the position of the satellites to match the respective ranges then your receiver won't be able to calculate anything.

Perhaps you should review what Ephemeris and Almanac's are all about. Really if this was not possible then mission planning software wouldn't work would it? And neither would GPS!

How do you think VLBI, SLR and other laser measurement systems locate those GPS satellites with reflectors? Of course GPS satellites can be located and it's quite absurd to suggest otherwise.

Interesting, I didn't know a consumer GPS can display the location of a satellite, any satellite, a TV satellite, let alone a military satellite. Which GPS unit can display that? , Just name a single recreation GPS. I have a Garmin 76CSx, and a Garmin-45. Maybe you can teach all of us which page will show where each satellite is located.

A GPS receiver does know where they are using calculations, but there is no way a recreation unit will, or can, show you that location. The original post was asking if he/she can use a GPS to locate satellites for setting up of a satellite dish, I assumed he was talking about a TV dish, like DirecTV or DISH.

As for ECXYZ, I assumed that since the OP asked what he did ask, he probably would not know what the heck is ECXYZ. In fact, I would bet the majority of GPS users would not know, or even care, what the heck is ECXYZ. But most everyone probably would understand what 3D means.

As for using lasers system to locate them with reflectors, I am sure the OP, and many other GPS owners has one right in their backyards, or maybe they can borrow one from a friend. I sure don't have one. Do you? Maybe you can use your laser, or your fancy GPS, to help the OP to locate and setup a satellite dish.

I really don't want to drag on this discussion, since it gets us nowhere. But I do want to give the OP the simply and straight forward answer he/she was looking for.

Yes can understand from your comments why you wouldn;t want to drag this discussion on as quite frankly you really have no where to go.

What a load of hoohah. The orig query has been covered and if you want to take your silly reasoning to the extreme then just about every GPS will show the general sky view although in generic terms but the underlying principle of this sky view is no hidden secret squirrel stuff. Geez the data was able to be downloaded from a GPS45 almost 15 years ago.

And what a stupid comment about "let alone a Military satellite" ???? Like this sort of comment highlights some misconstrued thinking that GPS are up there hiding somehow!!!!! Arh what can one say? the GPS sats have an extremely predictable orbit and to bring this military rubbish into this is simply ... arh well rubbish

As for a straight forward answer, well that's already been covered

as well as putting other myths in the correct context.

SatNav,

I think there are a few different questions here, each of which deserves a different answer.

Firstly, the OP's original question: I was wondering if i could use my gps to locate satellites for fta receiver reception and setting up of satellite dish. Answer: No! No recreational GPSr will give you the coordinates of any satellite (GPS or otherwise), other than the basic "sky view" plot of where the GPS satellites are currently located overhead - but not their actual coordinates, and it won't show you where any other satellites (e.g. geostationary communication satellites) are located.

Secondly: Does my GPSr "know" the locations of the GPS satellites? Answer: Yes - that's part of how it calculates your location. But will it tell you their locations? No. (Apart from the basic sky view screen.)

Thirdly: Can YOU get the location coordinates of the GPS satellites? Answer: Yes, you can (in theory) - but not using your recreational GPSr! There are various software tools around that can calculate the GPS satellite locations on your computer, but you don't need a GPSr to do this - and I'm not sure what use it is to the average consumer-user, apart from general interest.

Hope this helps clear matters up!

What is an fta receiver?

A GPS receiver can help find the azimuth (but not elevation) of a geosynchronous satellite if you create a waypoint with the longitude and altitude, placing the lattitude at zero . I have done this for several WAAS and XM satellites.

A compass with inclinometer is a better tool for this if you know the azimuth and elevation from your location.

What is an fta receiver?

I assume the OP was referring to Free To Air television transmissions.

A GPS receiver can help find the azimuth (but not elevation) of a geosynchronous satellite if you create a waypoint with the longitude and altitude, placing the lattitude at zero . I have done this for several WAAS and XM satellites.

Nice idea - but my Garmin Summit HC won't let me create a waypoint with an altitude of more than 30,000 metres (which is not QUITE high enough to reach geosynchronous orbit! ), so I can't create a waypoint at the true location of a geosynchronous satellite. I guess if you create a waypoint with the correct longitude of the geosynchronous satellite, latitude of zero degrees, and elevation of 0 metres, this will be directly below the geosynchronous satellite, so it will point you in the right direction, but as you say, it won't help with the elevation.

Geosynchronous orbits are very high (approx. 35,786 km), so to a first degree of approximation, a geosynchronous satellite will be roughly the same angle below the zenith as your latitude from the equator. (That is, if you are at 30 degrees south of the equator, a geosynchronous satellite should be about 30 degrees off the vertical.) This is usually good enough to point a TV dish to get an acceptable signal.

A compass with inclinometer is a better tool for this if you know the azimuth and elevation from your location.

Agreed - this is probably the best approach.

julianh, Yes there did become a few different questions which started with the following which is completely incorrect and off track from the orig query



For pointing purposes the coordinates are really basically useless anyway as the more usefull numbers are azimuth and elevation/zenith but then there really is no purpose in trying to point a dish at a GPS satellite other then for very special purposes.

But the fact remains GPS sats can be located, this is not a theory, can be positioned, are not some secret squirrel stuff or play hide and seek military anything, they are navigation satellites in a very well defined and precise orbit, they simply have to be.

How about this (to put words in JCBI's mouth ):

I don't agree. You can not display the locations of (locate) any of the GPS satellites with your GPSr. You can not get a 3D position of any of the satellies displayed on your GPSr. You can only get the signals from these satellites. based on the signals, you can calculate where you are located.

Too my reading, I think the words I have added in bold type were pretty much implied in JCBI's original posting.

Implied? Assumed? Or whatever words you feel comfortable about, in hindsight to might be right then again you might not?

I read things as they are written, reading minds are not productive.

But then I will leave it up to your imagination regarding the bit and Don't know?

Hmmm ...

The first post in this thread (which has now gone WAAAAY off topic!) which even suggested that you COULD possibly get the position of a satellite (any satellite!) from a consumer GPS was - let's see - post number 4 by - SatNav!

Everyone else has (more or less!) stuck to responding to the OP's original question - which I think most of us took to be along the liens of "can you use a GPSr to display / output the location of a satellite?"

Answer: No.

(By the way - you might have sensed that I enjoy perpetuating a pointless debate as much as anyone! )

Oh good now "my GPS" has been assumed to be a consumer GPS?

That's right post 4 was in response to post 3 which stated you couldn't.

now you can't even read what was written! Don't forget the word GPS was included in the original text! Oh how conveniently forgotten?

Well my friend make what you wish and add your own assumptions to this statement "My GPS knows where GPS satellites are"

My GPS!

Yes I noticed especially the way you include convenient assumptions and conveniently forget critical wording. Yes there must be an art in this enjoyment.

Please do continue.

Do I sense a bit of pots and black kettles?

Let's provide the full quote from post #3:

Like MM have said, you can't locate the satellites using the GPS.

(My emphasis.)

That is, you (the user) can't get the location of a satellite using a GPSr. Nobody ever said that GPS satellites can't be located - only that you - the user - can't display the satellite's location with a (consumer) GPSr.

JCBI did not explicitly specify whether they were talking about locating GPS satellites or geostationary communications satellites, although it seems clear enough from the context that the OP was asking about using GPSr to locate a communications satellite for pointing a receiver dish. I think it is unlikely in the extreme that the OP would have access to anything BUT a "consumer GPSr" to be asking a question of this type!

Nobody ever suggested that a GPSr can't locate a GPS satellite - only that this information is not available to the GPSr user from the GPSr itself.

Your turn ...

I have been reading all of the posts during the past few days, and decided to pipe in one last time on this thread. I will make it very brief.

Julianh, You are right on.



and my prvious comment...

Is that so? So a GPSr can't locate a GPS satellite? Now lets see how this gets twisted around to suit the 'desired" outcome!

Oh how some people twist things around, all this talk of military rubbish and the like highlights what some peope are thinking.

As this post (#4) has appeared to be mentioned/questioned by some then what I would like to see is creditable comments that this is not the case.

And for those that have a habit of adding their own but irrelevant wording interpretation the facts are

- A GPS can not locate non GPS satellites
- A GPSr can locate GPS satellites

Credibility time now, deal with the facts as per the discussion to this point and forget your own back peddling.

Silly silly statement! Of course GPS satellite infomation is available to the GPSr user from the GPSr itself.

Some really need to think about what they are saying!

Now remember you are dealing with the statement that GPS satellites can be located and of course you can locate GPS satellites and quite frankly people who claim a GPSr can not lcoate GPS satellites lacks any credibility.