genny causing noise in vhf and stereo

Bt Doctur said:
Harsh is finding you floating and putting you in a body bag. Being a bit harsh is a reality that few people see.
Just way too many ways to die in the boating world and not being able to call for help does not make any sense.

Here`s a poll.
How many have a "GO" bag with life jackets, flare gun w/ lots of flare shells, whistle, mirror, lanyards to loop all the people together, hand held radio in a sealed bag if they have to abandon their boat in a hurry?
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Fair enough explenation. As for the ditch bag, if it wasn't for my first born I probably would not have one but I made one a couple weeks ago with everything but the lanyard.
 
Noisy ground loops are unlikely on a boat since the AC and DC grounding systems are supposed to be separate. So, unless someone hacked his boat's wiring, I wouldn't spend much time looking for a ground loop. Sea Ray wires their boats the right way. I know. I checked mine.

An audio ground loop at home introduces 60Hz hum into an audio signal because the neutral wire has resistance which encourages the power supply to find another way to ground, which often can be the shield of an unbalanced RCA type audio connector. You simply don't have that situation with a marine VHF or an audio system that's powered on the 12VDC system.

The converter and the refrigerators both contain circuits that generate a fair bit of electronic noise, which will appear on the 12VDC circuit. I noted that one of the refrigerators on my boat only makes that electronic interference when running on 120VAC. I can sometimes hear that interference on the boat's stereo while listening to my connected iPhone or the CD player when the refrigerator is running and I'm on shore power. Turning off the AC power to the refrigerator ends the noise. It's not so bothersome that I need to fix it, though the fix is trivial.

You're not going to easily find that kind of problem without connecting an oscilloscope to the power leads so I'd try a power noise suppressor. They're inexpensive. A cheaper fix might simply be turning off the converter and / or the AC power to your refrigerators while you're running the mains. A little experimenting might help. Try turning off circuits, especially on the 120 VAC side, one by one until the noise is eliminated. If the problem is the converter, simply run with it off. The engine alternators will keep everything charged up. You will want to switch on the converter once you anchor or dock where you can't plug in the shore power cords.

Here's an okay article: http://www.crutchfield.com/S-0qYrby...car/noise_suppressors_installation_guide.html
 
Xplicitlnck said:
Ok getting closer. The noise is only coming from the 2 cabin speaker's. The cockpit speakers are wired to an amp while the 2 cabin speakers are powered by the head unit. The noise is constant while the stereo is on but seems to be mimicking the vhf signals. For example when I hit the ptt button the speakers pop a little and when somebody talks u can kinda hear the tone of the person talking if that makes sense. Now my vhf set up is as followed. 2 vhf sets one Northstar and one raymarine running off a single antenna with an electronic splitter. Both vhf radios and electronic splitter are wired to the same power feed and same ground. Any ideas?
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Have you traced the noise down to only omitting from the cabin speakers or have you reduced it down to only the cabin speakers? Need to know what you have done/checked/tested up to this point.

You say the noise is constant with the stereo on, but what about with the vhf radio(s) off? Is the noise same or similar in all head-unit modes like CD, AUX, USB, etc?
 
Ok. Here was my test. Turned stereo on. Cabin speakers (connected to internal head unit amp) made alot of noise. Cockpit speakers made no noise. Cut power to amp and cabin speakers still made noise. Turned volume down and noise went away. Turned volume up and noise got louder. Went to the panel and shut things down one by one. Noise continued even with everything off. Went to the helm and turned everything off. Noise still there. Went to the vhf and hit the talk button and the speakers popped until I let it go.
Everything was done with all 3 engines off and shore power disconnected.
I have a fusion 700 connected to an external 5 chanel amp. Also connected to a tv via rca for sound. TV only runs off of 12o.
 
radio makes noise when vhf is off as well? Try grounding things together, head unit to amp,. It would cheap and easy. Radio makes noise only when vhf is on? May need shielding on the vhf antenna. I would ground vhf directly to head unit, & amp . Would be worth a shot
I had identical buzz with engines off, never turned on vhf, so don't know
 
Thank you very much. I love ideas keep em coming.

Just a thought. Since my stereo is 12v and my tv is 110v and they're connected via rca cables for sound could this b a cause. 2 different voltage units connected?
 
I would definitely disconnect the RCA cables to test - it could be setting up a ground loop.
 
Ok well I got rid of the vhf noise by simply disconnecting the 2nd vhf and removing the splitter. Won't do that again. . Now the speakers still have the noise. Extremely annoying. I disconnected every wire one by one on the back of the head unit and nothing. Put a closer ear to the speakers and noticed only one speaker is making the cracking piping noise and the other speaker does not
Just very low volume. .. any ideas
 
Just buy the Honda and put it on the platform!! I hear it doesn't kill you as fast as the bilge genset
 
sdleo26 said:
Just buy the Honda and put it on the platform!! I hear it doesn't kill you as fast as the bilge genset
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Ohh man you just went there didn't you! I guess I deserve that after what I did to the other guy. That was definetly strategically planned tho:smt043
 
Sounds like you had a couple of issues going on at the same time... Down to one speaker making noise? Does that noise go away when all of the AC power is turned off? If so you probably have what is known as inductive coupling going on. If your speaker wires are routed next to an AC power wire for any distance at all the magnetic field created around the AC wire will inductively be imposed on that speaker wire and end up as a 60 cycle hum on the speaker. Check out how your wires are routed...
I had a situation where the televisions and blu-ray players were putting a lot of noise into the sound system. As it ends up there was a ground loop issue through the inverter when it was turned on and it was feeding current through the RCA connections between the video equipment and audio equipment. The inverter manufacturer couldn't do or recommend anything to help the situation. Ended up replacing the RCA cables with a Tos-Link optical cable and Geffen optical to RCA converter. The Geffen converter does the appropriate Dolby conversions; problem solved...
 
I've turned off every single object in my boat one by one and all together and that one speaker still made noise. I wouldn't call it a hum it would best be described as very loud rice Krispy cereal, same sound level at any volume. I even turned off the internal amp in my head unit and it still made noise which completely boggled my mind. I also disconnected my tv and rca cables from the head unit and nothing. It's weird because I installed the stereo 2 years ago and never had any issues. And since the install I have not changed or touched any wiring.
 
Xplicitlnck said:
I've turned off every single object in my boat one by one and all together and that one speaker still made noise. I wouldn't call it a hum it would best be described as very loud rice Krispy cereal, same sound level at any volume. I even turned off the internal amp in my head unit and it still made noise which completely boggled my mind. I also disconnected my tv and rca cables from the head unit and nothing. It's weird because I installed the stereo 2 years ago and never had any issues. And since the install I have not changed or touched any wiring.
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I am thinking it could be a bad ground wire on the speaker itself. Also, did you try replacing the speaker with another speaker to see if it is the wiring or a defective speaker?
 
Wylie_Tunes said:
Speakers do not have ground wires, so please dont add one. Doing so, will certainly let the magic smoke out of the head-unit.
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Hahaha no I wouldn't add a ground I think he means a bad connecting in the negative side of the speaker wires.
 
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