scanning a next frequency channel in a synchronous scan mode in response to {TAIL ~ the failure}, wherein {HEAD ~ the implantable device} scans a frequency channel for a same time interval as the external device when in the synchronous scan mode 
scanning a next frequency channel in a synchronous scan mode in response to { TAIL ~ the failure } , wherein { HEAD ~ the implantable device } scans a frequency channel for a same time interval as the external device when in the synchronous scan mode
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH