Hello to all ¡
I would like to add some corrections to the good post of Beaupower 32.
However, the German FuMOs were not equipped with the PPI (Plan Position Indicator) display system that is so familiar in today's radars, but a simple A-scope display instead.
That´s not correct. All the FuMOs with Lobe switching had a "J" or a "B" display, not the primitive "A".
BTW, a conventional display is far more precise than a PPI.
Also, a lot of Allied ships, lacked PPI displays even late in the war because It was very expensive and difficult to upgrade or change the earlier radar sets. By example, the Type 271 was not equiped in the first series with PPI, but only with a common "A" display.
Discounting the fact that the PPI is not an Allied invention, but a German-British invention (both countries discovered this display in 1940 allmost simultaneously).
The main advantage of PPI displays is that You can understand the pips like a map (far more easy than in a conventional display), but It´s less accurate.
All the late war Allied fire control had
one master "B" (or "J") display and various
slave PPI displays (the Mark 8 mod3 or the late Mark 13 mod0 are fair examples of this).
Therefore, they could hardly detect more than one target at the same time, and bearings were not very accurate either.
No, that´s not exact also. The prototipe "Seetakt", which carried lobe switching and the late war set FuMO 26 (1943) or the earlier FuMO27 (with lobe switching of 1941) were far more precise than allmost all the previous Allied radar sets of the 1940 and even mid 1942 years (like plain Type 284 or Mark 3).
When We compare accuracy, the only radar sets similar to the FuMO 26 were the US Navy Mark 8 and the British Type 274/277. The bearing accuracy of those 3 radars was very similar between them, not exceeding the 50 metres of bearing accuracy and the 0,2-0,5º of angular azimuthal accuracy.
The lack of PPI was one of the reasons German capital ships were so redundant and equipped with three sensors
Again, this is not exact.
All the warships carried at least two gunlaying radar sets, because of redundancy security If one set was disabled.
It had nothing to do with lack of acccuracy or similars. By example, the mid war set FuMO63 "Hohentwiel" had a master "B" display and 1 or 2 slave PPI displays, like the Allied ships. This is even more
marked in the late FuMO 8x "Berlin" surface series (a "B" or "A" display and 2 or even 4 PPI slave displays).
I hope this will be helpful