notch module 110 failure for example the microcontroller 106 closes the bypass switch 164 when no interference is detected for which the notch module 110 is used to filter conversely the microcontroller 106 opens the bypass switch 164 when interference is detected and the notch module 110 is to be used to filter such interference as shown in fig8 the notch filter block 158 includes a filter 165 which may be for example a filter having a reject band that is approximately 15 khz wide at u2212 40 db the reject band of the filter 165 may be fixed at for example a center frequency of 150 mhz or at any other suitable frequency at which the if of the mixer 150 is located although the notch filter block 158 of fig8 shows only a single filter 165 as shown in fig9 a second embodiment of a notch filter block 166 may include a switch 170 and multiple filters 172 178 in such an arrangement each of the filters 172 178 has a notch frequency tuned to the if produced by the first mixer 150 additionally each of the filters 172 178 may have a different reject bandwidth at u2212 40 db for example as shown.