Stereo in the M1009, I hear my engine in my speakers!

[Gunfreak25]

So I finally slapped the stereo system in the M1009. The power is coming from the diamond shaped 12V supply on the firewall. I also have a cigarette lighter socket under my dash that feeds from the same 12v supply, I use it for small 12v stuff and charging my phone for trips.

The stereo sounds great and I love plugging my phone into it to listen to my internet radio on the go. But when it comes time to charge my phone from the cigarette lighter socket with the proper charger adapter, I hear my alternators squeeling in the speakers.

I don't have an antenna at the moment since I really only listen to my internet radio. I noticed the cell charger adapter cord acts as an antenna for the radio if I hold it up to the roof!

 

[paladin1176]

Wrap it in tinfoil to shield it from the alternator noise.

 

[w3azel]

In our Humvees and MRAPs hearing the engine in the radio speakers usually meant a bad ground somewhere in the system.

 

[MarcusOReallyus]

In our Humvees and MRAPs hearing the engine in the radio speakers usually meant a bad ground somewhere in the system.

Yep. Clean up your grounds, and you can also run a capacitor between the power lead and the ground close to the radio.

Might not help, though. Cell phone chargers are notorious noise makers.

 

[Gunfreak25]

Thanks guys, the cell charger is not making any noise, the noise starts when the truck is started and is coming from the alternators. I'll see if napa has what I need

 

[glassk]

Ground strap on engine to frame is pro-billy loose ,...

 

[Warthog]

On the factory alternators there was an external noise suppressor. Most of them have disappeared over the years. Maybe you can add one.

 

[blackhueys]

I have had that in the past. You need to look up online ground loop noises or related and it will give you a plethora of info to this issue.