Should be added to the manual that the range boresight needs to be close to the target to be able to lock it up.
Seemed to be trivial... ... to be able to track a target, you need to follow it in both angles (Fi1/Fi2).
As Fi1 displays only the 3km magnified area of the range boresight, you can only lock it up if it is visible in Fi1.
Hpasp Free SAM Simulator, "Realistic to the Switch" (U-2 over Sverdlovsk, B-52's over Hanoi, F-4 Phantoms over the Sinai, F-16's and the F-117A Stealth bomber over the Balkans.) http://sites.google.com/site/samsimulator1972/home