Your Pioneer receiver already has a tuner in it, which is why it's called a receiver. The Marantz is basically useless to you in your current system but, if you still want to use it, two interconnects (RCA plugs) from the outs on the Marantz to the AUX in on your receiver will work. You should be able to pick up radio stations with just the rear antenna if you have any in your city. An outdoor AM/FM antenna will work better for picking up more and distant stations as jdsmoothie suggested. The Marantz could serve you in a second system in your bedroom or garage, used with powered speakers if you wish.
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