You will need a din for the radio end and a RCA plug for the amp. Here is a link to buy one for around 20 bucks. Most standard din plugs will not fit your radio so best easies way is to buy one made up for your specific radio. http://www.ebay.com/itm/8-PIN-MINI-DIN-LINEAR-CABLE-YAESU-FT-817-FT-847-FT-840-/350415986192
. This is one source, there are probably some others.