Buzz from speakers

[airborne_spoon]

When I watch TV I have the audio hooked to the radio via aux cable. Randomly I get buzzing noise from the speakers. Sometimes loud sometimes soft
My TV is 12v and plugs into a cigarette lighter plug inside the trailer.

I get no buzz when listening to the radio via BT, only aux.

How can I eliminate the buzz? Could a ferrite bead or a ground isolation work any recommendations on either of that would work?

 

[Olyteddy]

Ground isolating transformer might do the trick. Can you plug a set of headphones into your TV to see if the noise is part of the audio? If it isn't then the transformer should fix it.

 

[airborne_spoon]

Ground isolating transformer might do the trick. Can you plug a set of headphones into your TV to see if the noise is part of the audio? If it isn't then the transformer should fix it.

I don't have any headphones but if I use the TV speakers it sounds as it should no buzzing or anything

 

[Olyteddy]

Get one from Amazon. Return it if it doesn't help.

 

[Contributor]

I think you may have noise on the 12VDC. Are you on shore power? I always used 1microF capacitor on all of my circuits power sources. 1microF from V+ to GND as close to the device as possible.

 

[airborne_spoon]

I think you may have noise on the 12VDC. Are you on shore power? I always used 1microF capacitor on all of my circuits power sources. 1microF from V+ to GND as close to the device as possible.

I'm on battery/solar power

 

[Contributor]

So, no power supply noise from the converter. Try turning off the solar controller to see if its introducing any switching noise. Since BT is clean, then its analog noise coupling on the signal. You need to isolate if its from the source or the amplifier in the radio.

 

[airborne_spoon]

So, no power supply noise from the converter. Try turning off the solar controller to see if its introducing any switching noise. Since BT is clean, then its analog noise coupling on the signal. You need to isolate if its from the source or the amplifier in the radio.

Yeah if I use the built in speakers from the TV it sounds fine it only goes to crap when I plug in the aux cable to the TV.

 

[John From Detroit]

Oh I have heard Ground Loop buzzing many times. I've even built devices to prevent it.
One thign Ive heard is that some of them may limit audio frequency response but.. Not sure how much..... I can tell you how to make one but not for 19 bucks.
This is a very common problem in audio installs

https://www.amazon.com/BESIGN-Ground-Isolator-Stereo-System/dp/B06XQYN77L

 

[Lou Schneider]

Ground isolation transformers do the trick 90% of the timework. Speaking as a former broadcast engineer, I wouldn't use a $20 transformer in a professional setting but you'll never hear the difference (except for the elimination of the buzz) in a home or RV system.

 

[airborne_spoon]

I bought this and the buzzing is gone.

 

[John From Detroit]

Like several of us said. Ground loops.. Very common.
I used to run a laptop on a 12 volt converter what it did to the attached radio (it was a communications computer) was.. Evil I mean Evil.. due to the common ground and digital noise.
Wound up isolating the Laptop and running on internal when I wished to use it to type on the radio (I read all the yammering when the country switched from analog to digital TV about poor reception that radio I mention can push 100 watts into the wire on Single Sideband (AM mode Voice) and I can talk to most of the Contential US depending on band and time of day.. In Digital Modes (PSK-31) I turn the power down to around 30-40 watts and have Cards confirming contacts in Spain, Germany, Russia, Italy. Radio to Radio direct. no relay systems No internet.