Add Mute Signal Help?

[winnipegsubaru]

Hey guys,

I am new to these forums, and hoping that someone can help me out. I am upgrading my factory nav system in my car with a KNA-G510 unit. This unit isnt fully compatible with my OEM head unit.

This unit produces audio thru a line leval mono signal (the head unit is suposed to detect this audio and mute everything else) However this is what isnt compatible.

So what I am looking to buy / build is a circut that will detect the audio coming out of this line level mono signal and then trigar a 5 volt mute signal that will connect to the mute pin on my OEM head unit.

So essintaily as soon as the circut detects audio over this mono signal it will turn on the mute wire. When the audio is completed it will turn it off. Maybe the off will have a 2 second delay as well.

Can anyone help m design this circut?

Thank you

[Perry Babin]

Is there any DC voltage on the nav output that goes up/down with the audio from the nav unit?

Black probe on a known good ground.

[winnipegsubaru]

none that I know of.

I was thinking of building a Audio detection circut (of some kind) that would then instantly open a switch to allow the 5 volts to control the mute.

I have found lots of audio detection circuts by google searches. I just dont know how to modify them to do what I want.

Thanks

PS if your interested, the Nav that is being used is a Kenwood KNA-G510 being hooked up to a stock Subaru legacy screen. There is lots of info as to why it doesnt work... but not much on how to get it to work.

[Perry Babin]

You need to know for sure. Go measure the DC voltage when the nav system is producing output and when it's silent.