XM Radio is a satellite base radio, which is subscription based and transmits from two satellites orbiting the earth. This service was launched in 2001. One popular feature of XM is the ability to listen to one channel for a prolonged period of time on a road trip as the signal doesn't fade as you leave a city. There is also a huge selection of radio channels ranging in wide variety of musical genres. Since the radios don't physically have the music stored in them, however, it is possible that there will still be issues with your reception.

Car Receiver

If you have a car receiver, you know that the XM can drop out at seemingly random times (e.g. going under a bridge). This is because the satellite signal can't reach the antenna for some reason. The radio actually picks up a signal from two different things. If you are in the open air, you are most likely picking up the signal directly from the satellite, but if you are driving in an urban area, you are probably picking up the signal from a terrestrial redirector. Read the directions to your receiver to get to the set-up screen, which shows the signal strength. There should be two indicators, one for satellite and one for terrestrial redirectors. Move your satellite antenna until you get the strongest signal possible. The terrestrial receiver will be high if the satellite signal isn't. The best place for an XM antenna is on top of or on the rear view window of the car. XM has kits, which allow you to attach it in these places safely and run the cables back to the receiver without damaging any part of the vehicle.

Home Receiver

XM Home kits are a little bit trickier, but if you aren't getting good reception you may not mind the work. The satellites for Sirius XM are over the equator so it is very important that your XM antenna is positioned with an unobstructed view of the south This might be more difficult than it sounds as your home stereo may be located in a room with no southern pointing windows. If this is the case, you may need to move the home receiver and antenna to get the best sound. Also, if you have an existing satellite dish, which you no longer use, you can connect it to help boost your signal.

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TSS Radio: How To Get The Best Sirius/XM Satellite Signal