Audio dropouts (1 Viewer)

I love listening to SIRIUS in my car but lately I've been getting more momentary dropouts than ever before. Usually 4-5 on my half hour commute in the AM. I travel from Nassau to Queens County in NY. Anyone else share this problem. I use the ST-2

Hmm. I have never run into this problem. Well, trapped under a bridge I will run into it, but not normally. Which model is your unit, and any chance your antenna cable could have been screwed up?

As stated, I have the ST-2 mounted on top of my dashboard. I suppose the antenna connection could be bad but then I don't think I would ever get a strong signal. I lose signal under an overpass or tunnel of course.

I'm wondering if it has to do with satellite location. Where are you located?

Robert,

I can almost definitely tell you why you are getting the dropouts.

Sirius satellites hover in a higher orbit than XM satellites. For
this reason the signal cannot carry underneath overpasses. This
was a huge problem for me when I had Sirius in my car. The
service would go completely off-air whenever I stopped for gas
or at a bank teller drive-thru because of the overhead roofing.

Sirius has attempted to combat this problem by installing
"repeaters" in many areas. However, from what I have read,
there aren't enough of them being installed to fix the situation
in all areas. I live in a suburb 55 miles outside of NYC and in
this area the dropout problems have still not been addressed.

XM, on the other hand, has their satellites lower in the sky so
you don't have these same dropout problems. However, to be
fair in my reporting, I will say that because of the XM low orbit
there have been reports of signals not reaching city buildings
quite as well as Sirius.

I rarely have this problem either. I am in my car for over 8 hours a day around philly and the only time I seem to lose signal is under a bridge or bypass. I would check your connections. I never lose mine at my bank either. I have lost signal at certain gas stations but not too many.

Brent,

You may be in a "repeater-filled" area.

I think part of it may have to do with which area of the country you are in.

I have tried both services - though admittedly, it's been a while since I used XM. But when I had XM the biggest problem I had was dropouts. Driving through Western Kansas, where there are no radio stations (you can hit "seek" on your tuner and it just rolls and rolls) XM had terrible performance for me. In, out, in out. Whereas with SIRI I have not had that problem no matter where I am in KS.

In other forums, I've heard similar from those in other "outback" areas (NorthWest Nebraska, Montana, Wyoming). Part of this is because XM is fairly to very reliant on their ground based transponder network. Their coverage pattern from satellite relies on their ground transmitter network to help supplement and push.

http://electronics.howstuffworks.com...ite-radio2.htm
http://www.cse.msu.edu/~partyka1/tableofcontents.php

Because of the way XM works, it inherently requires more land-based transmitters, which the company provided for in the larger markets in most of the US. (LA/NY/Miami/Houston/etc.). SIRI, with a higher eliptical orbit needs fewer transmitters and as a result, they used fewer.. which can impact you in areas like a city where you have tunnels, etc.

However, if you're in the middle of BFE, the difference becomes significant. The farther away you are from an XM ground based relay, the more spotty coverage becomes. So, the higher eliptical orbit allows for SIRI reception to be fairly solid into many areas of Alaska, Jamaica, Mexico, and most of hte nowhere flyover country that some of us live in

Meanwhile, XMs system is fairly to very well suited for the larger areas where you do deal with the tunnels, etc. ala New York, LA, etc.

This is basically the outcome of the different technology they chose. As Ron also pointed out, because of XM's relay situation, placement within HiRise buildings can be more difficult then SIRI just because of the technology used.

I won't say which technology is "better" or "worse" just that they both have fairly significant pros and cons.

As an investor, SIRI's higher orbit satellites allow them to avoid the quick expense that XM is expected to run into sometime aroun 2009/2010, when they will be required to replace at least one of their satellites (ROCK or ROLL) due to a design flaw that has caused a slight, but continual drift in positioning. XM is compensating for these kind of issues, but it does lower their expected investment window from a 15 year Satellite output to about 10.

So, while I'm nowhere near a repeater filled area, I have almost all open skies - no big sky scrapers near by. And because I'm in the "boonies" comparatively, I don't have an XM Ground based transmitter anywhere near me.

And that makes a big difference as well.

(Seriously, I need to campaign to Mod this forum

Robert,

I travel from Nassau to Queens for work. I too am experiencing more dropouts than usual. At work, I used to get flawless reception, but lately reception has been spotty at best. I'm waiting for Stern to be accessible over the internet, so I can listen to him that way. Until then, I will deal with the spotty reception on my Sportster.

Chris

I have been getting more dropouts the last few weeks too on my Sirius unit in my car. I have noticed the dropouts seem to be on roads with a lot of tree cover. My guess is perhaps that now that its summer, the leaves being in in the trees block the line of sight. Is this a logical guess?

Thanks, all your replies are appreciated. Like Benson, I suspected that tree cover might be causing a block to the signal but I don't know if that's possible. I travel on the Northern State Parkway into Queens and as Benson states, spring has brought heavy leaf and tree growth.

Ron, I understand the problem with lack of repeaters Overpasses have always blocked the signal but as Chris and Benson point out: the situation has worsened lately. Do you think the tree growth on the road could block the signal?

In any event, its not bad enough to send me back to terrestial---just mildly annoying as long as it doesn't worsen.

Yeah, like others have suggested, I think tree cover has
probably worsened the problem.

Glad to hear you are sticking with satellite.

I have noticed that the couple of tree lined avenues I travel (almost complete tree cover over the road, gotta love New England) cause dropouts on my short commute. They are momentary, but they are noticable. I never got dropouts before the green leafy season started.