A combination of a radio receiver with a detachable controller is presented. The catheter comprising a flexible sheath, a handle, a pull-wire, holes for irrigation in its distal tip, sensing means and electrodes. A combined signal of the received data signals is received over the shared spectrum. An OTRC value is determined for each sector of the plurality of sectors by varying the OTRC position and determining whether the sector meets a criterion for correctly reading data from the sector. The pulse width of the driving signal of the semiconductor switch is determined from the inverted pulse width modulated signal and the preselected RC combination.