In the back of my RX 330 stereo, there looks to be 2 antenna plugs. One is a standard regular sized antennae plug and the other is a skinnier plug. Can anyone tell me what the skinnier plug is exactly?
Reason I ask is because I have a hard wired FM Modulator that goes inline between the antenna and stereo, which is suppose to be much better than the cheaper cigarette lighter fm modulators, but the signal really sucks. When I have my aux player muted, and turn up the volume, I can hear a lot of noise. I'm wondering if that second antenna plug is messing it up. I've heard FM modulators on other cars that sounded great, at least like the best FM radio ever broadcasted, but my setup sounds like AM radio.
Anyone help?

 

What year is your RX330? I believe these use a diversity FM radio with two antennas .... one screened on the rear window and the little antenna on the back of the roof.

Personally I've never been impressed with the quality of FM modulators, especially in urban areas with lots of intefering signals. What brand/model is your modulator?

 

My RX is an 04. The FM modulator I have is made by Sony. It was actually in another car before and sounded very decent then. Obviously not for audiofiles, but like I said earlier, it sounds like the best FM broadcast station I've heard before.
I'm looking to buy the VaisTech Aux in adapter, but at $280-300, it's pretty steep just to be able to plug in 1 little component. I'm trying to wait out to see if the price will go down a little bit. $60-100 is what the avearage aux in adapter on other cars cost.