How to Modify the Alpine CDA-7990 to Accept an XM Radio Tuner
- 1). Locate the silver antenna input on the back of the CDA 7990. If there is a sliver antenna plug in the input already, pull the plug out and set it aside.
- 2). Insert the antenna plug on the FM modulator into the antenna input on the CDA7990.
- 3). Insert the plug at the end of the vehicle's antenna into the antenna input on the FM modulator.
- 4). Insert the plug on the end of the FM modulator into the input on the side of the XM tuner. The plug and the hole is the same size of a head phone jack and plug.
- 5). Find an FM frequency on the FM tuner on your CDA7990 that is not occupied by a radio station in your area.
- 6). Press the menu button on the XM tuner and select the "Frequency" option in the menu. Select the frequency you want to use by pressing the "Up" and "Down" arrows to find the frequency and then press "Enter" to select.
- 7). Turn on the XM tuner. You will be able to hear the XM tuner through the open FM station you have selected.
