? for those with roof rack and Sat. Radio

Just installed a factory OEM roof rack that the better half got me for the Holidays on my 2012 DC. My question is, have any of you experienced a loss of satellite signal with the cross bars extended?

Prior to installation, I had near perfect signal and service, but now, I seem to be losing it much more frequently. This only appears to happen when the bars are extended, and not while stowed. I do notice how close the rear bar is to the "sharkfin" and surmise that this is the culprit, but if so, why would Toyota offer the rack as a factory option?

Any thoughts, ideas, or suggestions? This is making me crazy on my 110 mi. commute each day.

Thanks,
Eric

 

Never thought about it, but I wouldn't be surprised if it did.

 

+1

 

I did lose signal more with the extended, so I just keep them until I need them.

 

Do they fit behind your back seat or somewhere else?

 

Not going to dispute your experience, but that result is certainly surprising. A small metal rod (ungrounded) would not normally block a radio signal. Instead, it's more likely to do the opposite as a parasitic antenna. That's the concept behind cell phone and similar (AM, FM, shortwave, etc) passive signal "boosters" or "enhancers." Of course, that changes dramatically if the rod is grounded (loses the parasitic effect) or as the size of the metal increases. A steel reinforced concrete building, for example, will virtually stop a radio signal dead.

Anyway, enough theory. I'm sure you're more interested in what to do about it. Do you have a reason for having the cross bars extended? If I remember correctly, the instructions say to keep them folded when not used. Absent that, perhaps the parasitic effect is working against you. Try grounding the rear rod (a small wire to a roof rack mounting bolt). Jury-rig it at first just to see if it works. If so, you can do something neater later. Not sure what you can do beyond that.

As for why Toyota would, if that's happens with the OEM version, the result would be the same with any roof rack. And, of course, some want a roof rack. At the same time, the best place for the antenna (any antenna) is on the roof. In this case, those two evidently conflict.

By the way, should point out that radio signals rarely perform quite as well in cold weather (the mixture of humid & dry air can cause strange effects, increasing performance in some cases, decreasing in others). This is more noticeable at higher frequencies. Thus, your changing satellite signal might be more related to the weather than the roof rack.

-

 

Stew,

Not to be beligerant, but, why then, does my Trimble R8 work when my Sirious XM, will not?

I have utilized the R8 through thick and thin, including "canopy, swamps", etc.

I am of the understanding that the Sirius radio is satellite based, and not RF based. Am I wrong to assume this? If this is indeed Sat. based, there should be no problem with reception unless I'm under heavy cover, or in a tunnel (overpass).

Please expound....

Eric

 

I noticed it once when I had the cross bars extended and two paddle boards on the rack. I was in northern sask., where i'm not sure how good the signal is anyways. I always keep them to the sides when not in use.

 

I had a 2011 FJ with the roof rack and satillite radio. The roof racks were directly above my antena and I had so many dead spots (with reception) that I cancelled my satillite service.

 

I have roof racks and surf daily, my crossbars are always out and my board is mounted daily and I never have had an xm reception problem? Strange indeed

 

XM radio uses the S-band specifically the 2.3GHz spectrum, a microwave band.

Cain- living in long beach, LA has quite a lot of repeaters so you don't have too many interruptions. Whenever I am in La I never really lose signal even when Im under a bridge.

Also if your not transporting anything on your 110 mile commute they would be better stowed as i know people have done research that they lower your mpg a little bit.

 

How am I supposed to know? Could be a difference in receiver sensitivity. Could be a difference in antennas. Could be something else. By the way, "Stew" is not appreciated.

The signal from a satellite is a radio (RF) signal (both XM and Sirius satellites use the S Band frequencies just above 2,320 MHz / 2.3 GHz). Everything that applies to radio reception (in these frequencies) applies to satellite reception as well.

 

My sincere apollogies SX By the way, "Stew" is not appreciated. I was not trying to offend, only direct my questions to you, as you had the most educated response. My bad.

It still, however, perplexes me that one satellite system works, while another does not.

I understand tht the Sirius XM transmits its content via a certain frequency, but, I was of the understanding thst all satelite signals depend on "line of sight", as the signal is transmited from the satellite to the user. I assume that since since the satelites' "line of sight" depends on its location on the horizon, therefore, if the satelite is low on the horizon, the weaker the signal becomes.

So, with that theory in mind, having a metal crossmember interfering with the line of sight for the satellite signal might explain my reception difficulties.

Your thoughts?

 

would it do with what satellites you are hitting and how low or high they are on the horizon. satellite radio doesn't hit repeaters as far as I know, hence its satellite radio! if the satellite is lower on the horizon at the time, overpasses and buildings have more of an effect. there are usually multiple satellites available at one time so this is somewhat negated, but can be seen from time to time.

 

That's pretty much exactly it.

It is worth noting that (as a rule) the shorter the frequency, the easier it is to block. Cell phone signals (~2400 MHz) are absorbed by a great many more materials than FM (~100MHz) radio, for instance.

Also, since XM uses an encrypted data stream, it is much more sensitive to interference and distortion.

In my experience (with a Thule rack) there isn't much you can do, except relocate/replace the antenna. The receiver in the stock radio isn't terribly selective, and the location of the antenna kind of sucks. But it's a pain to relocate it, and/or replace the head unit so... I feel you. However, it works well enough often enough I put up with it. Way better than listening to pig futures on the only FM channel you can get in the UP.

 

Doesn't surprise me if it would affect reception. My biggest complaint about SiriusXM radio is the pretty crappy signal strength. I've lost signal for a second just driving under a small overpass at highway speed, forget about it if you have wait at a light under an overpass or stop for gas station that has covered pumps. Seems to need a constant, very clear view of the open sky. So I would think a metal bar right above the antenna would definitely affect signal strength.

 

Mine usually never loses signal, until I put my Bajarack on. With it on I lose signal a couple times a day.

 

No problem. I was not offended. Anyway, describing all the possibilities is very difficult (and time consuming). To start with, all the higher radio frequencies are fundamentally line-of-sight (the higher the frequency, the more so - satellites use very high frequencies). As for communications satellites, they're usually in geosynchronous orbit over the Earth (their position relative to the Earth does not change). Those used in the USA were placed to always be easily "seen" from the USA and none are on the horizon relative to Florida (you should be getting a good signal).

Now the discussion switches over to the satellite receiver. There are many variables impacting how well the satellite device receives that signal (receiver sensitivity, signal processing, etc), handles interference (filtration, error checking, etc), and so on. Each manufacturer handles these a bit differently, trying to find the ideal balance between the many factors. This usually means one device will perform better in some manner, but less so in another. Of course, consumers like (or don't notice) when it performs better, but do get upset when it doesn't.

Now yet another factor, atmospheric conditions, comes into play. Over the last few months, we've been in a fairly high solar flare activity cycle. And, of course, solar flares, which generate massive radiation covering the entire electromagnetic spectrum (including radio), play havoc with satellites and even ionospheric radio propagation. You may have recently noticed occasional interference with your cable or satellite television, for examples.

There are obviously other factors as well, but I think you get the idea. In the end, I recommend folding the arms of your roof rack (at least the rear one) until it's actually needed (the easiest solution). There are threads on here discussing how to relocate the satellite antenna, but this leaves holes in the roof which must be dealt with. Another option is adding an antenna in another location, leaving the original antenna in place (no unused holes to deal with). Of course, none of this is going to help much if your problem is related to solar flares (which should die back down in a couple of months).

 

I just got my roof rack installed on my 2019 Tacoma Limited this past friday. The rear bar, when it is extended, is just above the front of the shark fin antenna. It is now causing satellite radio interference as before, I had no problems at all with reception. I did not think that would happen as thought the rear crossbar, when extended, would not cover the shark fin antenna.