Jump to content

Problem with FM Transmitter and Speakers


aloftnfurl
 Share

Recommended Posts

This year I've added a Mobile Black Box FM transmitter to our show for the benefit of those driving past our display, and now I'm getting a constant low hum thru the speakers that I have out for those walking past the display.

The MBB transmitter is mounted into a powered weatherproof enclosure (an irrigation timer box) that is mounted next to the LOR controllers.

I have a 3.5mm splitter plugged into the audio output of the LOR1602MP3, with the transmitter plugged into one side of the splitter and a set of speakers plugged into the other side of the splitter.

If I remove the splitter from the controller (with both the transmitter and speakers still connect) I still get the hum, but if I unplug the transmitter from the splitter the hum goes away.

My question is if this is just 'one of those things' that I'm going to have to deal with or if there is a better way to connect my transmitter and speakers to my controller?

Thanks!

Link to comment
Share on other sites

Look for an audio ground loop isolator. Radio Shack usually has them. They are most commonly associated with car audio. Put it in the path between the splitter and transmitter. Should clear it right up.

Link to comment
Share on other sites

you will think it a strange device since it only sits in the line between the source and output devices. it makes no other connection, but it works when its a ground loop problem. its a big wart on a cable. If everything you have its headphone jack connection add about 10 bucks to get to and from the RCA connections the GLI will have.

Link to comment
Share on other sites

I found the transformer (wall wart) sent with the transmitter to be the problem with my MBB. When I plug the unit into a USB port on my computer the hum went away. You may have to invest in a better transformer.

Link to comment
Share on other sites

Thanks for the suggestions everyone.

I ended up swapping out the patch cable between the transmitter and the splitter and the problem went away. (The one I replaced was one I had used to replace another cable that ended up having a short in one end. SHEESH!)

I appreciate the help!

aloftnfurl

Link to comment
Share on other sites

Guest
This topic is now closed to further replies.
 Share

×
×
  • Create New...