I put this up on the Hunter forum and got a few helpful responces, but have not solved the problem. I hope someone can help me with this.
I need help with a installation I am doing on my Hunter 40.5 sailboat. Over this winter I decided to put a TV on board with a DVD player. I purchased a LED TV as they are very power miserly and the thin screen can be mounted close to the wall (taking up less space). I also purchased a 12 volt DVD player. The LED TV runs on 110 volt AC ,but has a transformer in the cord that converts it to 19 volt DC. I purchased a 12 volt DC to 19 volt DC converter to power the unit on the boat. I have all the parts set up at home to bench test them together. I am using a 12 battery as a power supply, when I wire the TV up thought the DC converter the TV works fine and to my amazement only draws 2.3 amps at 12 volts, great. My problem occurs when I wire up the 12 volt DVD player. I wire the player to the battery and use phono plugs to the video input on the TV. What I get is bands of “noise” on the screen and a hum out of the speakers. I have been told that this is a ground loop problem, or a 60 cycle feedback. Does anyone know how to eliminate it?
I have tried using a different 12 volt battery to power each device, that will work fine (no feedback), however when I put a jumper wire to both negative terminals of the 2 batteries ( duplicating the boat’s common ground) then the feedback returns. The other thing I have done is use a small inverter instead of the DC converter, so powering the TV though it’s normal 110 volt plug and transformer and having that connected to the same battery as the 12 DVD player. This works fine ( no feedback ), however it now draws 3.6 amps 12 DC. I would like to go the DC converter route as the amp draw is considerably less.
Help
I have tried these suggestions from the Hunter Forum, first I connected the TV to a wall outlet and left the DC to DC converter connected to the battery with the 12 volt DVD player. With this combination the TV played DVDs fine no feedback. I then re wired the TV though the DC to DC converter and installed a ferrite choke on the 12 volt input to DC converter, no help. Next I put the choke on the output of the converter, again no help. I next tried it in the 12 volt input to the DVD player, no help. I then tried the choke in the output phono plugs to the TV from the DVD, no help.
I then put a capacitor electrolytic, 35V, 1,000 microfarad on the converter output again no improvement.
The last thing I tried was installing a wire from the chassis of the TV to the DVD player chassis, no change, and then to the DC to DC converter chassis, no change, then to the negative post of the battery, no change. There must be something I am missing.
Jon
I need help with a installation I am doing on my Hunter 40.5 sailboat. Over this winter I decided to put a TV on board with a DVD player. I purchased a LED TV as they are very power miserly and the thin screen can be mounted close to the wall (taking up less space). I also purchased a 12 volt DVD player. The LED TV runs on 110 volt AC ,but has a transformer in the cord that converts it to 19 volt DC. I purchased a 12 volt DC to 19 volt DC converter to power the unit on the boat. I have all the parts set up at home to bench test them together. I am using a 12 battery as a power supply, when I wire the TV up thought the DC converter the TV works fine and to my amazement only draws 2.3 amps at 12 volts, great. My problem occurs when I wire up the 12 volt DVD player. I wire the player to the battery and use phono plugs to the video input on the TV. What I get is bands of “noise” on the screen and a hum out of the speakers. I have been told that this is a ground loop problem, or a 60 cycle feedback. Does anyone know how to eliminate it?
I have tried using a different 12 volt battery to power each device, that will work fine (no feedback), however when I put a jumper wire to both negative terminals of the 2 batteries ( duplicating the boat’s common ground) then the feedback returns. The other thing I have done is use a small inverter instead of the DC converter, so powering the TV though it’s normal 110 volt plug and transformer and having that connected to the same battery as the 12 DVD player. This works fine ( no feedback ), however it now draws 3.6 amps 12 DC. I would like to go the DC converter route as the amp draw is considerably less.
Help
I have tried these suggestions from the Hunter Forum, first I connected the TV to a wall outlet and left the DC to DC converter connected to the battery with the 12 volt DVD player. With this combination the TV played DVDs fine no feedback. I then re wired the TV though the DC to DC converter and installed a ferrite choke on the 12 volt input to DC converter, no help. Next I put the choke on the output of the converter, again no help. I next tried it in the 12 volt input to the DVD player, no help. I then tried the choke in the output phono plugs to the TV from the DVD, no help.
I then put a capacitor electrolytic, 35V, 1,000 microfarad on the converter output again no improvement.
The last thing I tried was installing a wire from the chassis of the TV to the DVD player chassis, no change, and then to the DC to DC converter chassis, no change, then to the negative post of the battery, no change. There must be something I am missing.
Jon
