mark_wilkins

Regarding XM antenna placement: In many metropolitan areas with plenty of signal repeaters, you can put the antenna in the rear strut bar and get very good reception. However, when you drive outside the range of those signal repeaters (say on a cross-country trip) your reception is going to be highly dependent on what direction you're going and where you are. Your antenna MUST have line-of-sight to the satellite through the window to receive a signal from it, but the terrestrial repeaters do not have the same requirement.

Honestly, I think that with a good install the antenna looks fine on the roof. Here's what I ended up doing. (Note that my philosophy on this install was that I wanted the best possible XM reception and did not find a roof install inherently offensive as long as it looked professional.)

My installation

For those who are interested in such things, I talked about some of the tradeoffs involved in this choice in this thread on another board:

Antenna Placement

Bottom line is that if you live in the right place or drive in the right place you may have great results with an install that doesn't meet the specifications, but meeting the specs might just get you a lot closer to no-dropouts, which is where I'd like to be.

-- Mark

w8lifter21

iTrader: (1)

This is what I did with both of my antennas(XM, and Sirius). Where I am, northern suburbs of Chicago, Sirius seems to get better reception than XM does. I drove down the same road, RT. 60 if you are from this area, multiple times and there were a few times that I got a distorted signal, but never completely lost, with XM, while I had no problems at all with Sirius. Either way, i'll take it because of the stealthyness

mark_wilkins

Sirius may be less sensitive to placing the antenna there because the satellites tend to be higher in the sky.

Neither service recommends an installation like that, but if it works well, so much the better!

-- Mark

CAN0802

Just curious, how exactly does a ground plane antenna make contact with ground if you are putting it on the roof, if you do not scrape the paint and expose the base metal? I have heard the argument about placement before, and really don't see the need for contacting the metal. From what I have found, the only reason the manufacturers want the antenna placed on the roof is for the best reception (no obstructions) and having a steel base for the magnets to cling to solidly. Aside from that, the antenna seems to be grounded through the antenna wires to the receiver itself, and the receiver to ground.

P.S. I'm just an electronics geek looking for further understanding here, and possibly even learning something.

netminder32

Well...I had the OEM Sirius tuner intalled yesterday....works fine....
the dimple on the roof isn't too annoying either.

Thanks everyone for all of your help and advice.....!

sundevil67

So basically what you guys are saying is that I can install my Sirius antenna in the strut bar and get perfect reception around town, but when I take a road trip to LA or something and get out into the middle of nowhere, I probably won't get a signal. That is really fine with me because I have 20GB of MP3s, CDs, and Tapes to get me through those rare trips. I think the trade off is worth it to get it off the roof.

sundevil67

Can't really tell, but these look like some other options for Sirius radio rather than installing that ugly box on the roof of my car. Anyone know what this stuff really is??

https://www.1stnissanparts.com/index...ath/21_197_199

CAN0802

No, what is being said is that inside the car you might have an occasional loss of reception, but that they happen so infrequently, it is hardly noticed.

mark_wilkins

Many of the people who are saying that live in Southern California or the south part of the U.S. Remember that the farther north you go, the more of a problem this may be.

Placing the antenna on top of the roof is not a perfect cure for dropouts, even in Los Angeles, and placing it in the strut bar is definitely worse. How much worse depends on where you drive and how much.

Note that Sirius may be very different than XM as far as how well the strut bar location works. Sirius' satellites follow a different orbit that tends to place them higher in the sky most of the time, and I'd bet that that's much better for strut bar reception.

Given my experiences with XM reception, I would not gamble on the strut bar location being a good place for an install if long road trips *at higher latitudes* are what you're planning (say a drive from Chicago to Portland, or somewhere in Canada.) If the look of a roof install really bothers you, maybe that kind of a drive won't ever be an issue for you anyway.

As for me, honestly having one of the latest car antennas like the Terk XMicro2 on the roof is totally inconspicuous. The only people who ever notice mine are the ones who stare at 350Zs all the time, and nobody's ever said they thought it looked tacky who saw it in person.

sundevil67

Something very unexpected just happened - I turned on my car in the garage to do something with my head unit, and the Sirius channels came in perfectly! How do you explain that?? Now I am getting more confident about the strut bar location. The other option I am thinking of is replacing the rear-wiper squirter. Is there any reason it would work better on the roof than it would on the rear window? I think it would blend nicely with my tint and be less noticable.

mark_wilkins

Both Sirius and XM use terrestrial repeaters to supplement their signal, and these repeaters often work indoors or other places that you may not be able to get a satellite signal. I use a handheld XM receiver at my desk at work, and on that receiver I can tell that the signal is coming entirely from terrestrial repeaters and the satellite signal is blocked.

Also, some building materials allow the satellite signal to pass through better than others, although if you put more than a few inches of wood in the way you probably won't be able to receive anything from the satellite.

The reason placing the antenna on glass is not recommended is that the antenna's designed to take advantage of sitting on a large piece of metal to improve reception. Just like putting the antenna on the strut bar, it's not that it won't work, just that it may cause worse dropouts in marginal conditions.

Anyway, because of the terrestrial repeaters, your garage is not a great test for these marginal conditions. If you really want to test the strut bar location, put your antenna there temporarily and drive a hundred miles or so out into the desert. I'd recommend heading north first and then south (for XM users -- thst should matter less with Sirius), and if you don't find the dropouts unacceptable, maybe the strut bar's just fine. Realize that if you go somewhere with a lot of trees you'll get a different result, though.

Ultimately, this is all about how much interruption of your music you consider acceptable (and there will ALWAYS be at least a little) and how dedicated you are to hiding the antenna. Only you can balance those things off against each other. All I'm saying is that there's a tradeoff involved in any decision that doesn't follow the manufacturer's recommendations.

-- Mark

sundevil67

Mark,
Thanks for your thoughtful response. From all of the photographs that I've seen of the strutbar location, it is actually attached to metal (see below). The reason I am having a tough time is because I am not really a do-it-yourselfer, and I would have to pay an installer to move it to each position I want to try. I am mostly worried about theft as opposed to aesthetics, as the antenna really advertises that I have satellite radio, and then of course one could assume that there is a more expensive system within. I don't have one yet, but I am planning on installing one. The other location I am thinking of, underneath the spoiler, should work as well as it does on the roof according to much of the information I've read. However after seeing the installer put his hand over the antenna and having it cut off completely, I don't understand how it could work at all from under there. Oh well, I guess it is just going to be some trial and error before I get it to the perfect location.

sundevil67

Has anyone tried something like this (originally made for the Titan) attached to the rear view mirror? I think this is the only other option aside from the roof that I would ask my installer to try because I think it is the only one that will actually work. I am just too afraid of the strut bar location or anywhere else inside the car. Anyone adventurous tried this?

http://www.grubbsperformance.com/Mer...ode=TitanAudio

dcmidnight

I installed mine right behind the 3 gauge cluster on the dash. Have no reception problems whatsoever. Drove out to WV didnt drop out once, only dropped out once on a 6 hour trip to Myrtle Beach. Perfect place to install it IMHO, no degradation in reception quality at all.

dcmidnight

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sundevil67

So there is no clear line of sight to the satellite at all? Do you have a picture of this? Man, I just still don't know what to do here. The installers are telling me there is no way it will work unless it is on the roof, and some folks on the forums here and on siriusbackstage.com are saying that it should work in these hidden locations no problem. Others are saying that the reception will suck. Agggg!

hondagal

I've had my Sirius antenna in both the strut bar, on the strut bar and on the dash. My final decision: on the dash. It's sitting on the small solid area between the defrost vents. It fits great and I don't have reception problems aside from any usual interference. I have the smaller square antenna and not the latest round one, which, I hear, has really good reception.

Give the dash a try, it should work fine for you. I like it there because it blends into the dash, it's not an eyesore on the car and most of all the signal strength is strong. I receive satellite signals only most of the time too, rather than terrestrial signals.

Try it, you may like it. If not, then put it in the strut but make sure it has an 'eye' to the sky where you put it.

There's more than enough antenna wire so you could attach it in multiple places temporarily, for testing, and then make your decision from there. That's what I did.

Good luck.

Metalaxe

Just a little more info from me on this. I still have the antenna located in/on the strut bar location. Still works as always. I did comment that it does lose connection in my garage and under overpasses.
My recent findings are: I just bought an Acura TL with XM already installed. The antenna is on the roof in a painted cover. (Comes from the factory this way) It works in my garage and and under freeway overpasses. I guess it all depends which is more important to you on the Z. Keeping the clean roofline, or having reception not cut out in these locations. If the antenna were able to be in a painted cover on the roof, it might look a lot better. It sounds as if the installers are telling you correctly in regards to placement on the roof. They don't want you coming back in saying, " I lose reception in garages etc." since it is in a hidden location. Good luck.

dcmidnight

Mine has been sitting comfortably on the dash for three months now. I only lose reception when I am in underground parking garages, otherwise, I have absolutely no problems whatsoever with the location.

guitman32

iTrader: (15)

I installed the SIR-ALP1 to my 9855 roughly a month ago, and after some research, opted to place the antenna in the strut bar location. The reception in my area was OK, with dropouts occurring only when in parking garages or going under the occasional bridge.

Then, I had tint installed. I went with a high quality metallic tint, which I knew might interfere with the satellite signal, but I decided to take my chances. As expected, after the tint install the Sirius reception went to zero. There were still a few stretches of highway that I could get a signal, but in 99% of the places I drive, there was no signal. So, I moved the antenna to the behind-the-gauges location, and I can happily report that reception is back to how it was when mounted in the rear strut location, if not a bit better. With this location, there are less dropouts under bridges, and reception is more reliable in downtown locations (around tall buildings).