signals from e g the position receiver 30 indicate a change in location greater than a wide threshold indicating that the receiver 10 has moved substantially completely out of the area in which the initial autoprogram was executed in any case in non limiting embodiments based upon a tv transmitter 39 s height above average terrain haat data that can be stored in e g the medium 28 the receiver 10 can access a transmitter database in e g the medium 28 to identify neighboring areas for additional potential channels for which to scan in addition to or in lieu of the channel map comparison described above additionally or alternatively a reception prediction algorithm such as the longley rice algorithm can be executed by the processor 18 to determine which channels are potentially available given the height of the receiver 10 in addition to or in lieu of using gps as a position receiver multiple means may be used for determining the location of the receiver for example reception of stations of known geographic location can be used as a determination of the location of the receiver 10 yet again a last known location of the receiver 10 may be used to predict the current location of the receiver 10 e g based on historical scan patterns the processor 18 may always execute the partial scan of block 38 at a certain location anticipating movement to another location or the processor can use time of day to make assumptions based upon prior usage in order to predict the location alternatively an absolute or relative pressure sensor such as a silicon based sensor may be used in the receiver 10.