Pulsing sound from radio when depth meter is on

M

Minnesota_Slick

Member I

• Apr 22, 2015

• #1

Hey everyone,

I've got a car stereo wired to one of the accessory switches on the 12 volt DC panel.
I also have an electronic Speed/Depth gauge wired to a different switch on the same panel.

The stereo works great as long as the Speed/Depth gauge is off. As soon as I turn it on, I hear an electric pulsing/popping through the speakers. I assume that I need to install a resistor of some kind on one or both of those circuits, but I'm a relative newbie when it comes to electricity. I would very much appreciate suggestions.

 

Guy Stevens

Moderator

Moderator

• Apr 23, 2015

• #2

Torroid beads on the power leads to the radio

Place some torroid beads with wraps of the power wires around them leading to the Radio power in and on the antenna lead. (Yes even if you only listen to the cd player LOL)

This is a good article that shows how to do it.

http://audiosystemsgroup.com/SAC0305Ferrites.pdf

I would add them to the power side of the radio too.

Happy Wrapping.

Guy

 

M

Minnesota_Slick

Member I

• Apr 23, 2015

• #3

Thanks, Guy!

I admit, my brain started to turn to mush after page 2, so I jumped ahead to page 11 where it talks about what not to do when wiring. I think I've got the gist of it.

 

Christian Williams

E381 - Los Angeles

Senior Moderator

Blogs Author

• Apr 23, 2015

• #4

When I tried to wrap the wire around a ferret, it bit me.

 

Guy Stevens

Moderator

Moderator

• Apr 23, 2015

• #5

Yep that happens

You need a ferrite toroid not a Ferret with an attitude.....

LOL

I did have a friend once with a ferret named Ferret Faucet.


Guy

 

M

Minnesota_Slick

Member I

• Apr 24, 2015

• #6

I've been doing some googling, and could the problem be that I don't have a properly grounded 12V system? Is there some kind of copper ground plate somewhere that I should be looking for? Something like this?

 

toddster

Curator of Broken Parts

Blogs Author

• Apr 24, 2015

• #7

That sort of thing is for SSB or Ham radio antennas. Or lightning rods, maybe. Not likely to be one on your boat unless the PO had one of those.

 

Guy Stevens

Moderator

Moderator

• Apr 24, 2015

• #8

Minnesota_Slick said:

could the problem be that I don't have a properly grounded 12V system? Is there some kind of copper ground plate somewhere that I should be looking for? Something like ...[/B][/U]?

Click to expand...

NO.

That is not this issue. You don't need to spend that money or that big a project.


Guy

 

P

Pat O'Connell

Member III

• Apr 24, 2015

• #9

Dynaplate

About thirty years ago we had a Datamarine Loran that would not work well until we installed a Dynaplate. The engine had been the ground. Then the Loran worked great for twenty years until it failed completely. Lot of foggy vacations on that old loran. Now we have a GPS. I presume that the Dynaplate improved ground fixed the problem? Spring polishing and reloading the boat now a big problem. When my daughter was around we always had young men basketball types that worked cheap and fast when they were not flirting. hmmm

Pat O'Connell
1981 E28+

 

Guy Stevens

Moderator

Moderator

• Apr 25, 2015

• #10

Different wavelengths

The dynaplate for the loran worked, but so would have some copper foil in the bilge. Receiving can be improved at longer wavelengths by the use of a bonding system to seawater, (like a ground plane in terrestrial applications.)

IN the case of a broadcast US based radio, it would not have a marked effect.

Guy

 

P

Pat O'Connell

Member III

• Apr 25, 2015

• #11

Grounds

Thanks Guy. We all appreciate your counsel on these issues. I'm going to try lacrosse players for the boat polishing. We are hoping for the best.:nerd::nerd:

Pat O'Connell
1981 Ericson 28+

 

frick

Member III

• Apr 25, 2015

• #12

good electrical ground

Guy Stevens said:

Place some torroid beads with wraps of the power wires around them leading to the Radio power in and on the antenna lead. (Yes even if you only listen to the cd player LOL)

This is a good article that shows how to do it.

http://audiosystemsgroup.com/SAC0305Ferrites.pdf

I would add them to the power side of the radio too.

Happy Wrapping.

Guy

Click to expand...

A good electrical ground is very important. Your 12 volt system is grounded to the battery, and your battery ground should be grounded to the engine. Some electronics are dirty... The can send noise down the power wires. A ferrite torrid create a choke which can stop the RF noise on the power lines.

Try a choke on both the red an black wires of the noisy device, and the radio.
Make sure your ground is good.
Rick