[REQ] Request for Comments on SJ-Radar Changes
 

When I have finished some other things I've been working on I will start on my second radar mod. The first one released about a week ago seems to have worked OK. There are a number of things I would like to address with this second mod, namely:

• Increase resolution of the radar screen.
• Add bearing numbers round the outside of the scope.
• Add bearing lines and range rings.
• Stop contacts appearing ahead of the sweep.
• Change the contacts so that they appear arced, instead of blobs.
• Add a digital range readout to appear at the bottom of the scope.
• Add a digital bearing readout to appear at the bottom of the scope.

I have done quite a bit of reading and with help from LukeFF and past forum posts, I think I know what the radar should look like. There are however some technical things I am not sure about.

The radar manual says that the bearing resolution is 5 degrees and the range resolution is 40 yards. Does anyone know if this 5 degrees referes to the angular width of the radar beam? If that is the case, then contacts should appear as at least a 5 degree wide arc, plus the target width, but I have seen pictures of radars with much smaller arcs of 2 degrees, but there was no date to the picture. The picture I have seen of the WW2 radar PPI seems to show the arcs at 5 degrees. Also, two targets close together should be indistinguishable. The working radar sets I have seen pictures of, for example the USS Cobia do not show a visible radar sweep line - I only recall having seen the sweep line on ATC sets. Was the sweep line visible?

I am including digital bearing readout, in lieu of there being a bearing train indicator. The operator's manual also advises operators to use a piece of thread from the centre of the display to the bearing indicator to get a bearing accurate to within half a degree (I think it was half and I only read it an hour ago).

Digital readout of range to target will appear on the scope, as there is no seperate range indicator unit. It won't be 100% accurate, I plan on a range accurate to within 0.2% of the actual range - according to operator's manual actual accuracy was 0.1%. Whilst I'm on that, what's the largest range anyone has ever seen a target at on the radar?

It's entirely possible I won't be able to get any or all of this working, but I have done some testing and have some fairly workable ideas on how to accomplish all of the above, but I might run into unforseen obstacles.

I'm looking for some comments on the stats for the SJ sets, as it's a lot easier to change things before I have created anything to change.

Let me ask the Cobia guys about the sweep line and the contacts making arcs on the scope.

The USS batfish has the "newer" SS radar, as opposed to SJ radar. I remember seeing a range counter and I think it had a bearing counter, but I don't remember. I'll take pictures of the SS radar set when I get down there next month.

As for range, in game I usually pick up contacts that are out about 30 miles/~52,000 yards, even though the max range on the PPI scope is 80,000 yards.

Thanks for the response, pics are always good :yep: . I'd love to visit the USS Cobia, USS Batfish and others some day - I don't know of any U.S. Subs near me, so it will be a long trip!

The max range of picking up targets is an interesting one, as it must be simulating the ships before they are cloned into the 20k (mile?) view sphere in game.

Supoposedly ships are spawned in ports and given routes to an end destination. They're not supposed to just spawn randomly in the middle of the ocean. On a clear day you can almost see out to 10 miles/16 km - usually a gray sihlouette at that range. I think the 30 mile limit is a parameter set in the radar files and can probably be changed like torpedo launch depths. I'll ask Cobia how far out contacts show up on their scope.