SUBSIM Radio Room Forums - Radar, Sonar explained

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Quote:

Originally Posted by Deep Six

Neal I'm not sure the SD Radar is working as intended, I'm on my first patrol and used some reknown to install an SD Radar unit.....Now this should only be able to pick up aircraft......Hum well it also has the magical ability to pick up surface craft as well.......I like the way when it picks up an aircraft the icon is a ship box untill classified but, hey i dont want to stay around on the surface for that long....Bug report the SD radar whilst working is NON-Functional in game, meaning there IS no radar installed..The sd screen is blank...(Yes I did try and turn it on)... I'll test some more but it has definately picked up a surface ship for me.... Got the operstor message...Contact bearing blah blah...Long range....Turned out to be an American Tanker......

Deep Six

Aye, I think you're correct. I believe this will be fixed.

Do the Devs even consider radar operation to be a potentially fun part of the sim?
They seemed to have dumbed down Sh4 for the casual gamer - most of the bugs or poorly working features relate to higher difficulty level operations.

Boy, this manual has got to be the WORST I've ever seen.

Trout

Quote:

Originally Posted by Trout

I could have missed it,but nothing on torp.Speed,range,size of warhead,& steam,or electric.What they left out,would fill another book,SHCE gave this 10 years ago in game,as well as SHIII. It isn't like they didn't have the model under them,when someone was copulating off makeing hard cash.:oops: :hmm: SJ radar,& PPI scope put the lid IJN's coffin.

Lifted from http://www.cs.cmu.edu/~tlm/silent.html#torps

Torpedoes, Radar, and TDC

Dud torpedoes can be a real problem before the end of 1943. You can lower the number of duds by having the torpedoes strike obliquely rather than at right angles. I try to have torpedoes strike at an angle of 30-50 degrees. After 1943, duds no longer seem to be a problem.
I leave at least 5 seconds between firings because of prematures: The second torpedo will sometimes detonate in the wake of the first if they are launched with not much time between them. Setting torpedoes too shallow (less than 3 feet) seems to increase the number of premature detonations, too.
The estimate of the distance to a ship is an overestimate by quite a bit until the ship gets within a couple of thousand yards. Use the radar to get accurate distances.
The radar can also help you estimate a ship's speed. 100 yards a minute equals 3 knots. Be sure to account for your own movement...I'm working on a scenario to help show how to use the radar for TDC inputs.
The SD radar tells you how far away a plane is but not what direction. If a plane is low enough, it will appear on the SJ. Watch for small blips away from the convoy.
Use the offset dial on the TDC for ships that are turning at the time you fire. The TDC assumes the target will be moving straight ahead on the course given at the time of firing. If the target is turning, it won't make as much progress in that direction and using a non-zero offset can account for that.
A rule of thumb is that each degree of offset on the TDC gives you a spread of 17 yards for each 1000 yards to the target, assuming they will impact at 90 degrees. For example, if I launch two torpedos, one with a 0 degree offset and one with a 2 degree offset at a target 1000 yards away, the spread between them will be 34 yards. At 2000 yards, the spread will be 68 yards. There's a table at Jim Atkins's site with the exact values, but this rule of thumb will get you to within 10 yards of the table values for offsets of 5 degrees or less at a distance of 3000 yards.
(Note to the geometrically minded: This rule of thumb works because the limit of sin(x)/x [x in radians] goes to 1 for small x. The difference between the angle in radians and the sine of the angle is less than half a percent at 10 degrees, and less than half of a thousandth of a percent at 1 degree. Most of the error in my rule of thumb comes from approximating 1 degree as 0.017 radians. But 17 yards per 1000 yards per degree is easier to figure in my head than 17.5 yards and is good enough for all but long range shots. )

So ho do you get the Radar to work?
I can't turn it on at all in the school missions unless it's already activated at mission start.

Patch 1.1 "fixed" the issue w/ radar working on early boats as it was "not installed". Now, for some reason, this applies to the school missions so no working radar.

My radar won't even TURN ON.....

"... For sonar ...
I find that the hydrophone is completely functional between 60 to 80 feet depth to keel. I suppose if you are using metric, that would be between 18 and 24 meters depth to keel...."

Actually, you will get occasional sonar operation at 54ft and steady operation at 55 ft. Nice thing about this is you can still see with the Attack parascope. There is no bottom limit to the device.

-Pv-

Quote:

Originally Posted by Radtgaeb

My radar won't even TURN ON.....

Same here. And I bought a set with my renown in Pearl! What's the point if I can't turn it on? Argh! :damn:

Of course, if I had a decent manual or even PDF documentation which might explain some of this. Oh, what's the use. :roll:

Question here: when I click on the "Estimate range to contact" switch, my sonarman gives me no response. Only when I click on the Menu button will he give me a contact. If so, shouldn't this be reported as a bug?

Fleet subs moving very slowly decks awash (in good seas) or at radar deptch would be able to detect contacts using their top mounted hydrophones.
However, a sub at periscope depth would readily detect contacts (provided conditions were acceptable and sea life didn't interfere). Another SH4 bug!

More info here-

http://www.maritime.org/fleetsub/sonar/index.htm

Yours, Mike

I was fiddling with my radar today. I know how to use the sweeping SJ Radar but how does the PPI (PIP?) radar, the next scope over, work? I thought I had figured but i'm not quite sure. I was fiddling around changing the range on it and such but I dont seem to understand the varying spikes on the scope

Would Someone kindly enlighten me? :know:

Quote:

Originally Posted by DeePsix501

Well first off, they are backwards from the manual and the command bar shortcuts. The PPI(plan position indicator) is the sweep, the A-scope is the line with spikes.:yep:

I have not fiddled with the A-scope much in the game but operation should entail rotating the beam until you get a contact(spikes). The position of the spikes along the line should indicate range.

Heres an example of another PPI I get to work on:
http://s153.photobucket.com/albums/s...t=Bild4412.jpg

And use :arrgh!:
http://s153.photobucket.com/albums/s...t=mk45shot.jpg

How do you activate range rings on radar?

Range rings on radar? I don't see 'em but one of Neal's Screenies with the smilie faces shows range rings.

Does the check box in the notepad at the sound station have any other purpose than to identify a contact and to get a range via sonar? Does it, perhaps, track that selected contact once you click the box (which doesn't seem to be the case)?

Quote:

Originally Posted by Radtgaeb

My radar won't even TURN ON.....

What kind of sub are you driving?