Furuno CN-24, Руководство по обслуживанию

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1-4
Note: In actual processing, the temperature data expressed by 9 bit binary number is
divided into two parts, the lower 5 bits and the upper 4 bits, and the temperature data
region is also divided into two sections. The time interval from the left edge of each section
to temperature signal indicate the value of the lower 5 bit or upper 4 bit number. This
configuration enables to shorten the length of the temperature data region.
Fig. 1.7 Temperature data region
1.3.3 Upward/Downward Sounding
The received echo signals are transmitted to the paravane receiver with
frequency-modulated form.
The echo signals received by the upward/downward sounding circuit are converted into 4
bits binary data which represent 15 stages signal level and then converted into FM signal
by the V-F converter.
1.3.4 Depth Data
Like the water temperature measurement, the detected depth is indicated by the time from
the left edge of the depth signal area to the depth signal (15 bit H/L code). However, to
shorten the length of the depth signal area, the depth data is divided into two parts (upper
6 bits and lower 6 bits) and inserted into the pause areas of downward and upward
sounding periods. See Fig. 1.8.