I'm busy putting together a Rev/Speed chart of all the ships.
What do you find easiest to handle using the hydrophones... Some examples:
- Revs per minute (count revs over a minute, 30 secs)
- Seconds for XX revs (count 20 revs, timing it)
And then this info would be put into the Recognition manual, something similar to this pic.
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This could be a very good idea.
I actually started doing this a while back (a year ago), but when I realised how much work was involved I gave up. I got the idea from modern subs that use this technique, but they can use the sonar in DEMON-mode (Demodulated Noise.. i think) that can count propeller blades and can give you speed based on propeller frequency and TPK (turns per knot), but they have computerized sonar... we only have our ears...
I'm not sure if SH4 is accurate for this, but it's worth a try if anyone has the time to do it.
Good luck on this project.![]()