FM Transmitter Setup

2010 was my first year doing a computerized light display. I had wanted to do one for years and before I started the most intimidating part was the FM transmitter. It's actually very simple.

The hardest part is selecting the right transmitter. People who like to solder seem to gravatate towards the Ramsey kit transmitter. I can't solder to save my life. I first bought the Whole House Transmitter. I did everything I could to make it work, spent time on the phone with their tech support, but in the end nothing I did got the signal to the street. Then I ordered the MobileBlackBox Eclipse 4000. The sound quality is awesome, the range is very good, so much so that I use it with the antenna collapsed so the signal "only" reaches the street. Make sure that you get a stereo transmitter and not a mono.

Do not be tempted to get the 1W or 5W radios. I have a friend who purchased the 5W radio and you can pick up his signal all over town, except for right in front of his house. If you have too powerful a signal you will get a visit from men dressed in black from the FCC.

Some radios with have a RDS feature that allows you to broadcast digital data with your transmission. These can also be bought seperate and put between your transmitter and antenna.

Next, you need to find a frequency to transmit on. You want to find the darkest frequency you can. One way is just by flipping stations, but the better way is to go online and see what channels are being used and pick the one furthest from any other station. You do not want to broadcast over a licensed station, big no-no. This link is good for finding empty frequencies: http://radio-locator.com/ .

Hooking up the transmitter is very simple. You plug in the antenna first. On some of the Chinese radios you will burn up the radio if you turn it own without the antenna hooked up. Then you plug in the power, then use a regular audio cable to plug the transmitter into the headphone jack of your computer. Turn on the radio, set the frequency and you are done.

Be sure to test the range of your broadcast. If you have your antenna all the way collapsed and find you are still broadcasting too far you can put an antennuator between the transmitter and the antenna to further reduce the power, often you can also use a power supply with less voltage too.

Some people put their transmitters on timers, I just put mine on one of the Light-O-Rama channels. Some people complain that if there is anything else plugged into the electrical circuit as the radio that they get a hum, I have not had this problem with the MobileBlackBox.

At our display we also get some foot traffic so I put some radios in the bushes tuned to the transmitter with the volume loud enough to just be heard from the street, but not from the neighbors. I have to remember to make sure the radios get turned off before the transmitter or else they blast static really loud.