SD and SJ Radar mast question
 

Using this as a reference ...
https://commons.wikimedia.org/wiki/F...to;0821201.jpg


My sub (Balao) looks just like this. Its a late 1944 career.


I just read an article off fleetsubmarine.com that says the SJ was mounted on a retractable mast.


Odd, the only retractable mast I have is for the SD radar.


Am I missing something here? A special command to get the SJ to telescope?

You are not missing a thing... The game of SH4 is based on SH3, which probably had parts of SHII still in it... but the gist of the matter is that there are three raise / lower / rotate spots on the submarine "build" in SH4. Attack periscope takes one, Observation periscope takes another, and the SD takes the other. No way to add another without having access to the source code. Whatever you do, don't look at the motors and engines... I think you should be able to have one screw forward, the other reverse for tighter turning, especially when under electric, but ~no~... not possible either... Still, it is a good game for being 15 years old (counting SH3 in that), in spite of its shortcomings... :salute:

Ah that explains it. Thanks.
Odd the devs missed that.
There is so much detail in this game related to the subs and they missed this one detail.

SH4 was based off of SH3, SH3 used a new engine and had no carry over from SH2.

That said, SH3 was designed with the Uboats in mind and their associated technology. SH4 was built off of SH3 directly. Not an unheard of way of game development except in this case the dev team that made SH3 didn't all move on to make SH4. This was apparent upon release when the game was a **** show of bugs, broken mechanics, and legal technicalities. Digging into the game files you'll find most of the SH3 files present in the SH4 install, although I haven't tested it I'm nearly certain you could run both from the same install somehow.

Now PB is correct in stating there are 3 commands for raising/lowering masts in SH4, because that's what we had from SH3. The last one wasn't a radar mast however, but was the snorkel. The ability to raise/lower a snorkel was implemented in SH3 and worked as intended (changed out the air inside and provided air for the diesels to run). The fleet boats didn't have snorkels and so this was left unused, but still present in the game (albeit a broken mechanic now).

This mechanic was discovered and used to raise/lower the SD radar instead by modder Anvart IIRC. This added some needed historical accuracy to the game. Now as for the SJ radar, I've not known it to be an extensible mast during the war. Later versions on the GUPPY boats may have been, but that was due to the larger conning towers. The SJ radar could however be used while submerged by coming shallow enough that the periscope shears cleared the surface.

Yeah thats how I use it. 45 feet in calm waters is enough to get it working. 40 feet in rough waves, but that exposes some of the conning tower deck in troughs.


Sh4 v1.5 lets you use the SD on a retractable mast native, so no modding needed for that.

That's one of Webster's GFO mods, I'm afraid. I wish it were stock.

I only used one of his mods.
Unless he put it in the Websters 100' Clear water mod, then I have no idea where it came from.
Maybe one of the other mods incorporated it and never gave credit.
In any case, its always worked since I noticed.

Not to stir the pot, but FWIW fleetsubmarine.com indicates


https://fleetsubmarine.com/wp-conten...1/sj_radar.jpg

SJ RADAR:
The next major advance came with the installation of SJ Radar, beginning in mid-1942. Unlike the SD unit, the SJ was a directional radar, which could be used to sweep the surrounding sea for targets. The primary limitation on range was the height of the retractable mast, radar being limited to line-of-sight.

Right, but it doesn't cite a source for any of its information on the site that I've found. They also have an Ohio class SSBN as their banner. On the other hand this manual from the Navy has no mention of the SJ being extendable, but does mention the SD being extendable. http://archive.hnsa.org/doc/radar/index.htm

The more I look into it the more I think fleetsubmarine.com got it wrong.
Here is the specification sheet, with installation diagram.
No extendable antenna.
https://maritime.org/tech/radiocat/sj.htm

In every picture I have seen it has been mounted on a horn like that, with what I assume is a support tube leading down from the head to keep it stable while the boat moved to decrease vibration, and sometimes I dont see the support tube.

I have never seen a picture of the SJ extended, ever.

That said, in order to get a heavy wind catcher antenna like that to be mounted on an extendable tube they would need the same hydraulics as the periscope.
Pump up, gravity fed down, and just as thick to keep it from shaking.


Interesting factoid: The SJ radar, since its directional and short range, was used as a telegraph/morse code transmitter to other submarines when traveling in a wolfpack.
Since it cant be heard on radio, and the directionalality and short range means it cant be picked up accidentally it was a perfect way to share secret comms.