future. In light of the reallocation of the UHF-TV channels above channel 51, we propose to limit future secondary point-to-point use of TV STL and TV relay stations to UHF-TV channels 14-51. We further propose to grandfather existing stations that operate on the UHF-TV channels above channel 51. We seek comment on this proposal. 4. TV BAS Sound Channels Section 74.603 of the Commission's rules provides authority for TV BAS stations to use an aural broadcast STL or intercity relay station licensed under the aural BAS rules to transmit the aural portion of a television broadcast program. This use is on a secondary non-interference basis to programming of aural broadcast stations. It is our understanding that the current practice within the
a result of the upcoming auctions. This means that if TV BAS operations cause harmful interference to these primary services, they must cease operation immediately, regardless of whether this occurs before or after the end of DTV transition. Secondary TV BAS operations are also required to accept any interference caused by these primary services. 4. TV BAS Sound Channels Section 74.603(b) of the Commission's rules provides authority for TV BAS stations to use an aural broadcast STL or relay station licensed under the aural BAS rules to transmit the aural portion of a television broadcast program. This use is on a secondary, non-interference basis to programming of aural broadcast stations. In the Notice, the Commission stated that its understanding of current