Lock-on is not possible if there is an altitude difference.

[vitaminBB]

You can lock on from 20 nautical miles at the same altitude. However,

if there is a difference in altitude, you cannot lock it even if you point the nose at the enemy.

Is this a specification?

[diamond26]

Your target which is a DL track is at 25k and your radar antenna is looking 5-11. Unless you get your antenna elevation to the right place your radar will never see the target.

[vitaminBB]

After adjusting the antenna angle and selecting with the TDC cursor, I was able to lock on.

I am happy that the long-standing problem has been resolved.

thank you very much.