What frequency range? Additionally I assume you want to connect the audio out (maybe line audio) from the TV and listen to it on what? Phone to me implies telephone? Maybe you mean an FM receiver with headphones?
The guy here in the forums who is good with things like this is AudioGuru who could likely suggest a good circuit. The problem with most circuits like this is parts placement and environment. The majority of these little transmitters drift frequency with temperature, humidity and other variables.
Ron