There's also channels below 50 or so MHz. Going all the way to about 7Mhz. But these are used mostly for sending video to the head end, stuff like town council meetings and high school sporting events.
Also many cable systems avoid putting channels on ham radio bands, like 144-148MHz, 222-225Mhz and 440-450MHz. Because hams are quite ternacious about leakage from the cable into the air. Also the areonautical band just above the FM broadcast band is also avoided. Both services expect to be able to communicate to weak signal stations. Police and fire are less fussy, as they are channelized and their signals are usually fairly strong (as they usually only talk to their guys in the same town).
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