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Discussion Starter #1
Ok , first off , a disclaimer. I have no idea where i heard this comment .
so if i am completely off on this i blame it on old age ,dwindling memory, etc. :) :) :) :) :)
Is there a difference in how high above the horizon
the satellites are for the XM , and Sirius radios? Seems like somewhere i heard (read above disclaimer :lol: :lol: ) that the Sirius are higher above the horizon ,and might work better up here in the North , i am in northeast Pa. and riding around here in the mountains , and especially heading north of here , i am constantly loosing the XM reception. I thought that the Xm would cure the problems i had getting a fm radio signal, sometimes the fm works better than the XM does. ..
I have had the antenna both on thedash under the vent. and also mounted on top of the clutch resevoir . doesn't seem to make a difference.
Also note , i am not interested in sports , or talk radio, just want to listen to music. so the programming on either one would probably suit my needs.
Joe.
 

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The short answer is probably 'Yes'.

For some more details, you might want to click here for some info on the Sirius satellite coverage.

Sirius programming is delivered to its subscribers via 3 high power, Loral SS/L-1300 commercial satellites in an inclined elliptical orbit around the Earth. Unlike most satellites, which use geostationary orbits 22 300 miles above the Earth, the unique higher Sirius Radio satellite inclined orbit allows a somewhat larger coverage area.

The Sirius satellites have an average elevation angle of about 60 degrees as opposed to approximately 45 degrees for geostationary satellites. This higher elevation allows them clearer line of sight and fewer obstructions such as buildings and trees. The 3 satellites slowly orbit the Earth approximately 100 degrees apart and employ a "hand-off" method, meaning that only 2 of the 3 satellites are active at any given time to avoid interference as Sirius is only allocated 2 different frequencies. One of the satellites over the U.S. will use frequency A and the other will use frequency B. As each one of the satellites leave the footprint of the continental U.S., they deactivate and hand-off their signal to another satellite which has just re-activated and is just entering the footprint of the continental U.S. Each of the 3 satellites spend approximately 16 hours over the continental United States, with at least one satellite over the United States at any given time.

Click the picture for an animated image of the satellite patterns of both systems.

Here's a website with some good comparison information between the two systems.
 

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Discussion Starter #3
Thanks Jon . at least i know i wasn't imagining things , i'm going to have a chance to try a Sirius in the next couple weeks.
Joe.
 

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Well FYI....let me share my experiences. My Sirius set-up has the same reception problems you describe.....but I'm in the south. I think that the trees and mountains are a problem with satellite radios in general....maybe not. I tried a different antenna, no change.

A couple of weeks ago we were in Asheville NC, and I thought that even in the trees and mountains I was getting better....but not constant reception.
Maybe that indicates that it gets better as you go north...I dunno.
This Sirius experience has been a bit dissapointing because of this. Seems that with the satellite or 3....they could send a signal that would rival that of FM......but it's not the case in my experience.
I did have the Sirius tech guy one time tell me that the signal (quality) of the transmission is very compressed. Said it had to be to get it to all those customers?? I don't know what that means exactly, except the quality is not near FM quality IMO.
Good luck with your quest.
 

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steve s said:
Well FYI....let me share my experiences. My Sirius set-up has the same reception problems you describe.....but I'm in the south. I think that the trees and mountains are a problem with satellite radios in general....maybe not. I tried a different antenna, no change...
The antenna needs to have an unobstructed view of the sky to receive maximum signal strength. XM does have a better terrestial repeater program, providing better coverage in the urban areas.

The standard automotive antennas that come with satellite radios are dependent on a reflective ground plane for best reception in both Satellite and Terrestial modes. Here's a quote from a technical review of Satellite receiver antenna construction and performance:
Both SAT and TER elements of roof-mount antennas require a minimum of six inches from sheet metal edge to provide satisfactory antenna performance.


Unfortunately, they didn't compare the same antenna installed without a ground plane. Bottom line, antenna placement is critical to optimizing performance
 

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The ideal location of a mobile antenna module is on the vehicle roof. Both SAT and TER elements of roof-mount antennas require a minimum of six inches from sheet metal edge to provide satisfactory antenna performance
So how do we accomplish this on a Goldwing? I suppose my Hoon mount is not ideal with the antenna stuck on the top of a 3x3 square of metal?

Do you have any suggestions for better reception on the Wing?
 

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The reflective ground plane makes a huge difference. Take the same receiver from your bike put the antenna on the metal roof of your car aprox. 10" from the windshield or rear window and you will probably have great reception in almost all conditions. It is very difficult to create that kind of reflective ground plane on a motorcycle. The worst part is the plastic body work does not make a good reflector. Place your receiver in the antenna signal strength mode from the menu and then move your antenna around until you find the location with the highest signal strength. I found that with my Sirius here in the southwest it workd best on the rear trunk lid just below the lip of the back seat upholstery. The only time mine cuts out is if I am very close to an airport or military base. There must be some radio interference. You can make it better but you just have to experiment. Short of putting a large metal deck on your trunk this is the best I could find and it is really OK. I rarely lose a signal.

Good Luck / Dave
 

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So is your mounted under thte trunk lid, like between the liner and lid, or on the outside? I've got to find a better place.
 

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Jon has shed some light on what Motorcylcemom was telling me this weekend. I have Sirius(nothing against XM, They have a channel I love and Howard is a plus) with the antenna mounted on a piece of metal strap that comes out from the passenger backrest. The only time I have every lost signal on the bike is in long tunnels(over 20 or so seconds traveling). She was saying that her XM cuts out in the mountains at times but seems to cut out less that her GPS's. I had always figured that the satellites were pretty much the same and couldn't come to a good explanation of why her experience was so different than mine.

By the way Jon, She says you are looking into a dash bracket for her to mount both GPS's and her XM. I have your mount and was thinking of doing the same thing this winter. If you get it done, I would be interested. I want the Calypso on the left, 2610 in center, and Ipod on the right. Let me know.
 
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