I have an old nexus instruments system v. 1.0 from the late 90s. The wind speed/direction display stopped working this past winter. I have checked the voltages as outlined in the manual at the display and they appear to be within acceptable ranges. When I power up the instruments (there are multiple transducers for depth, speed, etc. and a multi control), the wind direct and speed appear. The speed starts dropping very quickly and dispappears after maybe 10 seconds. The wind direction appears to be correct but disappears after about 40 seconds. Does anyone have any ideas about where to start looking? thanks!