Live Sports Radio low-band VHF FM Audio
The company Live Sports Radio has been using low-band (channel 2-5) VHF TV channels for no-delay live FM broadcasts within sports areas. They have been issued hundreds of STAs (Special Temporary Authorizations) by the FCC under FRN 0017507716 to operate on these channels, which are normally reserved for television. The broadcasts are intended to be received by fans in stadiums and arenas, providing live commentary and updates during sporting events. They generally use separate video (to tell people how to tune in) and audio (the actual sports broadcast) channels, with the audio being transmitted as analog FM compatible with broadcast receivers capable of tuning.
Wide-band multi-digital decode chips like the NXP TEF6688 cost about $5 in production quantities and radios containing the TEF6686 retail for around $70, covering the 65 - 108 MHz range plus extensive shortwave and mediumwave AM coverage. This type of chip is too expensive for a give-away promotion radio, so less expensive receivers, using chips like the RDA5807 covering 50 MHz to 108 MHz would be used. Off the shelf radios selling in the $10 range cover 64 MHz to 108 MHz, and with slight customization I believe the vendor could obtain $5 radios covering 50 MHz to 108 MHz, which would be ideal for this application.
The ERP of the transmissions is typically STA authorized at 5 watts. They have been specified to use the Trival AD-44/CW-AH2 which is quite inefficient at these frequencies and only rated for 10 watts input power. They should consider using a more efficient transmit antenna.