I know this has been covered, but I can't seem to find it. I have good xm signal from the antenna be mounted behind the tail lights where most people recommend. My problem is the transmission from my Roady II to the car radio, It sucks! If I grab hold of the Roady I get good signal. I remember reading somewhere here that there's a adapter that Y's off the radio antenna. Where can I purchase this adapter and how hard is it to install. Also, I would like to "direct connect" the power supply. This would require a device to step down the voltage, again wher do I get this adapter? Thanks in advance.

 

I went to a car stereo store and they direct wired it and my problems are over.

 

I have my antenna mounted on the dash by the windshield on the passenger side. My reception improved a lot. I don't have the Raody I have the Autoivox and it can be hard wired without and extra hardware. Can't help you there. Have you searched the radio dial for a frequency the is really weak to receive the XM signal.

 

I used a delphi xm fm direct adapter to direct wire mine xm myfi to the radio, i have a extra one un opened too, $20 shipped

 

Can you tell me how this adapter hooks in to my radio antenna and how hard is it to get to?

 

 

You plug your factory radio antenna into the adapter and plug the adapter into the antenna plug on your XM.
it also has a extra cig lighter plug to tie in where you want too. heres what it look like...

 

Mine is mounted to a small (4" x 8") piece of sheet metal that I painted black and screwed to the underside of the right rear fender top (over the wheel in the back of the coupe). The docs say the antenna works better when mounted to metal, not readily available in our cars, so . . . improvise :-)
Reception has been excellent.
Regarding the hook up, I have an XM Commander head (velcro to the ashtray cover), I stashed the interface up under the dash above the passenger footwell (just wire tied the components together and found a snug spot). Used one little fuse tap to the panel under the passenger footrest.
And I connected it to the stock sound system through the 12 CD changer harness under the right side rocker panel (just pulls off, velcroed on). Don't know if you have the 12 CD changer (I didnt) but I'm pretty sure all the cars are wired for it. There was an adapter that allowed me to just plug the XM output in there.
Works great, just hit AUX on the stock radio and the XM powers up and plays.
Very easey project, just take your time and run the cables nice an neat. Took a little bit of time to get the antenna run through the rear speaker enclosure to get to the back of the car, and running the head wire through the back of the center console to come out of the ashtray, but all in all, easey to do.