U-Boot Periscope Telemeters

Nikdunaev · 01-15-21, 07:59 PM

Quote:

Originally Posted by Pisces

I am the one that invented the speed trick.
(from the old days: https://www.subsim.com/radioroom/sho...&postcount=135) And the other scratch mark just under 15 degrees, for magnification adjustment. If I was unclear, I am not the person that made the RAOBF mod. That was a collective effort of Hitman, JoeGrundman and OneLifeCrissis. They don't seem to be around here much. Unless they visit subfora that I don't visit.

I have no clue what modding difficulties they encountered while trying to make this. My knowledge is skin deep. But I'm sure this was motivated by that. Lack of available resources in modifying the GUI to move the way he wanted it/work like the historical device. It must have been the best way to replicate it.

Much of how it works can be learned on the following site. It is a gold mine if you want to know more about everything connected to target acquisition, tracking and torpedo guidance (from both sides of the war): http://tvre.org/en/ They have an English and a Polish language version.

As mentioned in my above first quote. The magnification trick uses the mark at 14.5-ish degrees. If you calculate the sine of that angle, you get 0.25. In other words, one quarter. If you line up the low-zoom size to the mark, you get the high-zoom size at the index at the top. For correction of the AOB width in low zoom it is a bit more complicated, and I actually forgot. Maybe you can find it in the archives if you search for my name in OLC's threads. The top link should be a start in the right direction.

https://www.subsim.com/radioroom/sho...&postcount=222
And finally: https://www.subsim.com/radioroom/sho...&postcount=263

!!! Be aware though, the precise values and steps relied on that older mod. For use in current RAOBF/GUI mods make sure to consult the documentation of the mod. It's scales may differ.

Thanks for all the links!

Actually, http://tvre.org/en/ is where I got most of my questions from.

The scope and ring pictures above are theirs.
That article mentions that the device could be used for either magnification in real life, but does not give any detail.
So, given that there is no Optische Länge scale on the thing, and the two pointers work differently as well, in real life... I started wondering how it was supposed to work.

Why the two different eyepieces on the scope?
Does this have anything to do with magnification?
Apparently the ring could be mounted on either:

Also what is the purpose of the big knob in the lower left corner of the ring? I can not find any references to that one in the text of the articles, even though it is numbered in one of the photos.