Items you will need:
- TV with an audio output
- RCA to 3.5mm adapter cable
- any FM transmitter with a 3.5mm stereo plug
- any portable FM radio tuner with a headphone jack
Step 2: RCA to 3.5mm Adapter
These things cost about $3.00 USD at RadioShack.
Step 3: FM Transmitter
The 3.5mm stereo plug on the FM transmitter will plug into the RCA to 3.5mm adapter cable, which in turn plugs into the audio output of your TV.
You can buy one of these from Amazon.com for under $10.00 USD.
Step 4: Portable FM Radio Tuner
I guess you could use a full size radio with a headphone jack, but that would be pretty bulky...
You can buy one of these from Amazon.com for about $15.00 USD.
Step 5: Diagram
Once you're done connecting everything, just use your portable FM radio to tune into the proper frequency on your FM transmitter.
Use the volume control on your portable FM radio to set the volume to a comfortable level.
There you go! Have fun!
P.S.: You can also do this with a Bluetooth transmitter and Bluetooth headphones. As long as the Bluetooth transmitter has a 3.5mm stereo plug, it's the exact same concept!