摘要 |
<p>A radio frequency (RF) coupler comprises a first electrically conductive track (21) having a pair of terminations and a second electrically conductive track (31) having a pair of terminations. In one embodiment (Figure 1), the first and second tracks (21, 31) are arcuate, the first track (21) being mounted on a circuit board (23) fixed to a rotary shaft (11) and the second track (31) being mounted on a circuit board (33) supported on a coaxial bearing relative to which the shaft rotates. The two tracks (21, 31) are in radially-overlapping relationship. In another embodiment (Figure 2), the two tracks (21', 31') are mounted on coaxial sleeves. The RF coupler is used to transfer RF power from a first circuit on the shaft to a second circuit relative to which the shaft can rotate. Also described is a tunable notch filter.</p> |