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Originally posted by sonhouseYep big trees will interfer.. Dipole pretty generic.. I would go for something directional..
Even air. Ah, now I know what to do, just put the antenna in a
satellite....
Siriously speaking, I put the unit in one of the attic bedrooms
and got signal much better, even through the walls, didn't even
have to be in the window. But outside definitely is the key.
I wish I knew the exact path of the satellites, they say point the
antenna south but w directy overhead then
dissapear over the opposite horizon.
Oh well, have to do my best.
Make a dish from copper clad board..
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Originally posted by sonhouseIf you are near a truckstop you can buy a two foot out door antenna that fits on semi's. You can mount it outside like a dish for your TV and that should alleviate the problem. Costs about 60 bucks.
Anyone have a sirius, I got the home kit where you theoretically
can get the signal at your house but I get poop for signal, the
customer support person said to point the antenna to the west or
northwest, here north of Philly and I got a pretty unobstructed view
but zip for signal, it just goes 'aquiring signal' forever. I did have
a poor signal in ano customer support lady said to call product support.
But in the meantime, any help out there?
Originally posted by slimjimYou guys need to read my post and understand it.
If you are near a truckstop you can buy a two foot out door antenna that fits on semi's. You can mount it outside like a dish for your TV and that should alleviate the problem. Costs about 60 bucks.qu
XM radio uses geostationary satellites, they can be counted on
to have a fixed location in the sky. Under those conditions,
a nice big dish or a high gain Yagi can be used unconditionally.
High gain is good. The problem with high gain is you get gain
at the expense of BEAMWIDTH. Get that? let me say it again,
this time with feeling:
High gain antennas, low beamwidth.
Now how does that effect the situation for Sirius?
Sirius does not use geostationary satellites, they are like
the GPS system, a fleet of satellites in very elliptical much lower
altitude satellites, which means that if you use a high gain antenna
it HAS to be used with an aiming rig that follows the satellite.
That doesn't work well in this case because after a few hours
that satellite goes beyond the horizon and is out of radio contact.
There are three satellites in the Sirius network however, so two
are about the horizon at any given time. So if you have a high
gain antenna not only do you have to track a satellite as it moves
through the sky but when you lose track of one you have to find
the other one to re-aquire the signal, THEN start tracking it again,
see the problem? You have to use LOW gain HIGH beamwidth
antennas. Beam width means how far can you tilt the antenna and
still pick up some kind of signal. That can't happen with a dish.
you tilt it off 20 degrees and you can kiss the signal goodby.
The reason you can use a dish for tv is they use geostationary
satellites and therefore the signal path never changes, it follows the
antenna as both go around the earth at the same time, so from
the viewpoint of the ground, the signal is always in the same place.
Therefore for that application, a HIGH GAIN, LOW BEAMWIDTH antenna
works well. Not for Sirius however, its apples and oranges.
Originally posted by CenterNutHow bout I build a high gain antenna and I'll hire you to come
Well build a high gain arial and help me in the help me thread plz 😉
and steer it 24 7. What do you think? Should work out fine,
I can only afford minimum wage, 6 bucks an hour, works out
to 1,008 bucks a week.....
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Originally posted by sonhouseKOOOOOOOOOL I need some cash
How bout I build a high gain antenna and I'll hire you to come
and steer it 24 7. What do you think? Should work out fine,
I can only afford minimum wage, 6 bucks an hour, works out
to 1,008 bucks a week.....
And there will be times where you won't be using it so you can teach me guitar .. this is fantasic. and I get a holiday out of this country 😀
check download.com / sourceforge.net / freshmeat.net / spaceweather.com / nasa.gov for satellite orbit-tracking programs ...
or AMSAT ... or sirius ... could try the space_systems/loral site, too, it probably would just have an overview but you might find it interesting ...
maybe if you had two antennas you could get better coverage of the orbit, one pointed one way, one the other ...
any treelines in the way? ...
saw the little repeater unit from sirius on sale at fry's, i think, for $99 ...
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think i have seen an article about adding an extender to a dish antenna (increasing the diameter to increase the gain) maybe you could extrapolate ...
ARRL has an interesting amateur satellite radio handbook, but it predates sirius ... it does have antenna info for the amsats, you could find it on ebay or arrl's site ...
(edit: or interlibrary loan ...)
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Originally posted by sonhouseI did some of this stuff at uni. It is a long time ago, but if memory serves the reason it needs to be outside is noise. Satellite signals are normally weak, and the receiver's main job is picking them out of the thermal background noise.
You guys need to read my post and understand it.
XM radio uses geostationary satellites,
[snip]
Not for Sirius however, its apples and oranges.
The thermal noise of space or the sky is at 4K more or less. The thermal noise of a tree in winter will be 273K (if it is snowing). The noise of your (glass) window will be around 290K.
The glass or anything else will attenuate a bit, but will also add noise to the signal.
I think the signal strength, and the effect of noise will be the main differences to your radio ham experience.
So much for theory. You already have the solution - put the aerial outside. Good luck,
Gezza.
Originally posted by sonhouseI've had one in my semi for the last 4 years with no signal loss and I travel all over the US and Canada. I don't see what your problem is. Get one of those longer antenna that is sold in the truck stop specially designed for Sirius. Or buy an XM. I have both.
You guys need to read my post and understand it.
XM radio uses geostationary satellites, they can be counted on
to have a fixed location in the sky. Under those conditions,
a nice big dish or a high gain Yagi can be used unconditionally.
High gain is good. The problem with high gain is you get gain
at the expense of BEAMWIDTH. Get that? let me say it a ...[text shortened]... HIGH GAIN, LOW BEAMWIDTH antenna
works well. Not for Sirius however, its apples and oranges.
Originally posted by slimjimI was thinking of that, getting both. BTW for 500 bucks there is a deal
I've had one in my semi for the last 4 years with no signal loss and I travel all over the US and Canada. I don't see what your problem is. Get one of those longer antenna that is sold in the truck stop specially designed for Sirius. Or buy an XM. I have both.
at Sirius for lifetime membership which I did. I finally got around to
trying it in our car, a Santa Fe. Got signalus maximus and the house
was between our driveway and the southern sky which is where the
signal supposedly comes from. So the key is for sure getting the
antenna outdoors and I saw an ad somewhere for antenna cable
extentions which will let you get it outside mounted somehow.
Thats for the indoor antenna.
I noticed one thing bad, when you disconnect the power, all the
presets go away. I thought they would have put the presets in
a flash memory but its zip when you remove the power plug,
at least with my radio, a starmate. Anyone else notice that and if
there is any remedy?