Radar Ranging Tutorial?

[Singed]

Hello again,

Running RFB, RSDC and getting more comfortable with the game

Establishing a bearing with radar is of course pretty easy but I find that I am having trouble understanding how to establish an accurate range with the A-Scope.

I experimented last night (aka cheated to learn) with a daylight surface approach in fog, map contact updates on. Watching the PPI radar for bearings as I did a run around a small convoy to get ahead of them. When i went to the A-Scope to get range, I was totally confused.

I used the following assumptions, obviously some or all of which were wrong. (Or the radar is :)) But I'm going to go with the FAR more likely idea that I am wrong.

The A Scope scale is in meters (hence the x1000m label)
A nautical mile is 1852 meters.

So if the scale says 10, it would be 10000 / 1852 = 5.39nm
5.39nm x 2025 would give me a range of about 10917 yards.

However the ranges I generated are not even close to where the ships showed on the map measured with the compass tool.

Can anyone spot this newbies errors?

I've looked around, and at one point I think I remember that I found a good radar tutorial but I was brand new to the game, didn't create a link to it and I cannot seem to relocate it.

BTW: One of the few complaints I have about RFB is the default view of the radar screen (too far away for my tastes and I have to walk forward to see it well). Is there a mod that sets that default view closer?

[sharkbit]

I believe there is a mod or two out there that might help. I think Webster did a nice one and I thought someone was working on one that would give a digital readout of range.

I believe Webster(?? :06:) did a video tutorial on radar as well.

Try the search function in the SH4 mod section.
I might do a little looking as well.

:)

[sharkbit]

Try this:
http://www.subsim.com/radioroom/showthread.php?t=152097&highlight=radar

Video tutorial:
http://www.subsim.com/radioroom/showpost.php?p=1020754&postcount=209

There may be others.

:)

[Platapus]

Awesome tutorial. Is it stickified?

[KlassenT]

Aye, it's in the Bag o' Tricks. :up:

[Singed]

Ah, that is exactly the one I wanted to find, thanks for digging it out! I guess my memory was a little flawed and it does not cover what I was hoping it did.

However I think I have figured out that the accuracy or inaccuracy of the A-Scope over longer distances is dependent on the user being able to accurately read it. When the spike is some nebulous distance between two range marks, you are kind of making an educated guess about the reading and the math errors are a simple case of an old computer axiom... Garbage in, garbage out. A small error reading (guestimating) on the scope can translate pretty quickly to a big difference in calculated range.

Last night, I did a pretty "pure" stalk in bad weather using radar, sonar and even a few pings as to help estimate speed. Wound up shooting 4 fish in a small spread, at a target I never actually saw and hitting with 2, one of which was a dud. It was really quite intense watching the stopwatch and listening to the torps run at the target then hearing one thud and one boom.

Didn't sink it, but good enough for me!

I think I'm addicted now...

[SJFriesen]

How do you read the PPI radar to plot a course early game? You dont have Surface Radar for a couple weeks and I dont really understand how to manually read the PPI

[razark]

How do you read the PPI radar to plot a course early game? You dont have Surface Radar for a couple weeks and I dont really understand how to manually read the PPI
If you don't have a surface radar, the PPI will be blank, so there's nothing to read.

[SJFriesen]

Sorry got back into the game to look at the station. Its the A-Scope I was talking about sorry about that. How do you read it manually?

[razark]

Sorry got back into the game to look at the station. Its the A-Scope I was talking about sorry about that. How do you read it manually?
If you don't have a surface radar, the A-Scope will be blank, so there's nothing to read.


From reading another post of yours, I believe you're running TMO2.2. Instructions on operating the radar and TDC can be found here: http://www.subsim.com/radioroom/showthread.php?t=172535
But, as I said, if you don't have radar, the screens will be dark and unusable.

[SJFriesen]

Thanks alot Razar im checking out that link now. I think the thing that was screwing me up kinda was I had a contact reported and when I went to the A-Scope there was the white triangle but there was also a little green triangle (you can move the triangles on the a-scope and it changes the range indication.) Not the wave like on the link you provided. If I come across the situation again I will take a screen shot and post it to see if anyone can make sense of it.

[razark]

white triangle: This is the range input. Line this one up with the target blip, read the range of the digital indicator to the left.

green triangle: This is the TDC computed range. Use this to compare the calculated range to reality.


It can take a while to get the hang of using the new radar/TDC, but once you get the hang of it, it becomes second nature to do it. I've also used the range input of the radar to enter in visually determined ranges before the boat has radar. Ask the watch officer for the nearest visual contact, and enter that range into the radar. (Don't forget to convert. He reports range in feet, but everything else is in yards. Kinda silly to make it like that, but we work with what we have.)