| 摘要 |
An apparent wind indicator for indicating the wind direction relative to a moving sailboat. The indicator shows relative wind direction for both downwind and tacking maneuvers of the boat. The readout unit of the indicator provides one-for-one correspondence between incremental changes of direction for downwind travel and a much greater incremental change in readout for a given change in wind direction during tacking. The indicator employs a circular-track potentiometer disposed at the top of the mast of the boat and the readout unit is at deck level. In one embodiment the change in incremental readout as a function of wind direction changes for tacking is effected by shorting out a major portion of the track leaving two minor portions which are tied together to allow both starboard and port tacks to be read over a large part of the readout scale (i.e., the order of 330 DEG ). In another embodiment a plurality of differential amplifiers is used to effect the same result. The apparatus is adapted to be combined with other boat devices such as, for example, velocity recording apparatus, to give combined indications.
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