[quote=akdavisHmm...I have my doubts about the PPI clips shown. It is not from the same, black-and-white film as the A-Scope imagery, which seems in keeping with the quality of low-light film at the time. Furthermore, it is an extremely "clean" image, which suggests Hollywood interpretation to me. I suspect it might be from a movie.[/quote]

Here's some stills for you M. Sarsfield:

Radar Antenna shown before the radar screen clips:

http://i251.photobucket.com/albums/g...ubeAntenna.jpg

'A' Scope or possibly 'R' Scope :

http://i251.photobucket.com/albums/g...ubeA-Scope.jpg

PPI Scope:

http://i251.photobucket.com/albums/g...ouTubePPI2.jpg

I agree the PPI scope isn't from an SJ and doesn't look of WWII era. The clip of a radar antenna they show immediately before the two radar sequences looks like a polystyrene rod antenna, which is a fire control radar. I'm not sure these types of radar have PPI scopes.

My reasoning is this: The PPI image shows that the radar it is connected to has a very narrow beam, as the blob is circular, not arced, indicating that radar has a high bearing resolution, whereas the SJ set had a bearing resolution of 5 degrees. If you note on the PPI screen shown, it is also drwing its own range rings, which is not something the SJ set did. I'm not sure if other search radars did this during WW II though. Also, if the speed of the film is accurate, which given the fade rate of the scope seems like it is, then the PPI scope is connected to a radar head that is rotating once every 3 seconds, or 24 RPM. The SJ radar rotated at a max of 10 or 12 RPM, which would suggest that the radar was of a later era. Finally, the SS sets that replaced SJ on submarines were connected to the existing scopes, so no upgrades there either. Lastly, that PPI image does not appear to be receiving any sea returns, which normally would swamp the scope up to at least 2,000 yards and there would be a clump of light in the centre of the scope if that PPI scope were connected to a surface search radar, so I am guessing that it's attached to an air search radar.

Hmmmm... now you really peaked my interest. Batfish has electrical boxes labeled as SS RADAR, but the unit in the Batfish CT looks a lot more modern than the SJ-1 scopes. Might be a 50's or 60's era scope.

This will teach me to post without checking my references! I can't be sure that the SS sets were installed to use the existing scopes, or if they were replaced. There's no mention of it. The SS radars got a new 'B' Scope, and had a PPI and 'A' Scope, though the SS was produced too late in the war for service. ST used the 'A' Scope of the SJ and SV, first installed in August 1945 used the SJ scopes as well.

Would love to see some pics of the USS Batfish's scopes and range units.

Edit: Even if the scopes weren't replaced initially, they probably would have been over time with newer models.

Awesome! Can we ask how the state of the development is?

Regarding the question if green or red radar:

You have to consider that after the war the submarines had been updated with new technology. So it is unsure if the actual pictures are historically correct.

The pictures of the red scope are of the only remaining working SJ-1 radar, if I understand correctly.

In the movie "Below" where I think they had a fairly historically correct setting the radar screen was green.

http://ecx.images-amazon.com/images/...TL._SS500_.jpg

http://www.aotd-flottille.de/Bilder/greenradar.jpg

They also said 'Blow Negative' when they wanted to dive quickly, bless them. I'll take a look at my copy this evening. Those range rings don't look right, as far as I have found, built in range rings were not a feature of the SJ radar.

@Nisgeis

:rotfl:

You are right, the movie Below was okay but in detail...oh well. But I had the impression that the setting was historically correct.

The question is: If the radar on the cobia hasn´t been updated after the war.

You're right about the updates, though I think for claims of authentic WWII sets, they would check the serial numbers before making such a claim. State of development is me trying to work out if the radar bearings are all screwy, or if I just can't read them of the bearing indicator accurately enough. The bearings given by the radar are between 10 and 1 degrees to the left of the target, as if the radar has been lobed off to the left hand side by 5 degrees. This appears to be why the radar blips jump onto the screen well ahead of the sweep reaching them.

Does anyone actually use the radar to track targets? U.S. or German radar sets? Can you get an accurate bearing with the german sets, ie one that matches the periscope bearing.

As for red versus blue, sorry, I mean green. It's not a problem to change the colours. I think I've seen two sets of pic with the 'A' scope being green and the PPI scope being Orangey/Red. The one pic of a 'B' scope I saw, it was purple.

@M. Sarsfield, SJ 'A' Scope was apparently 5 inches and the SS 'A' Scope was 3 inches, so they are different scopes. The SS set also had a 'B' Scope, which was 3 inches, with a 4,000 yard range and was a bearing indicator. How big is the one on the Batfish and does it have a 'B' Scope?

I correspond with the Cobia museum frequently and thy swear up and down that they own the original radar scopes from the war years. So, I'll take their word for it.


The Batfish has about a 2 1/2 ft high cabinet that's about 2 feet wide and a foot deep. I think the scope diameter is 5 inches - only PPI. The knobs and dials are smaller on it than the old SJ sets. There are two doors on the front to access the electronics. Currently the rotating motor for the antenna is removed for repairs, but they wan't to at least get it rotating and then some day we'll get the cabinet/scope working.

Hmm, then why is there always a green radar? Be it in movies or games...Very strange...

Most game researchers probably go off of black and white historic photos and compare them to modern radar/ATC equipment. They make the incorrect assumption that all radar [PPI] screens have always been green. It won't be the first time that something in a game, movie, TV show, etc. has been wrong.

Another thing that I have discovered being around sub vets is that 20 vets in a room will sometimes give you 20 different memories. Small details escape a lot of peopel over time - especially 60+ years.

Assumedly you are right..So the big question has been answered. The radar screens were red.

Wartime SG Radar imagery:

http://www.history.navy.mil/photos/i...000/i00391.jpg

Batfish SS-2 radar
 

I took pictures of the Batfish SS-2 radar, BUT most software developers have not developed a way for my LG Trax camera phone to talk to Winblows XP :nope: . So, I will have to use my Fuji digital camera when I go back in two weeks.

The unit does have two scopes. The PPI is about 5 inches in diameter and the screen looks like it is orange. There is also a small 2 or 3 inch A-scope to the right of it that is probably green. There are two range dials that use the odometer wheels. One is in yards and the other one is in miles. They had red lenses and the wheels were white with black numbers.