AoB is what the captain on the target would see if he was looking at your boat. It's the angle off his bow (course) not yours.
There are several ways to get AoB.
If you've got the target course plotted than draw a line from your boat to the target and using the compass tool measure the angle between that line and the target course, that angle will be the AoB. Have the PK on when you enter this value.
Second you can just eyeball the AoB input dial and match what it looks like comp[aired to the periscope view, keep adjusting as necessary. The white X is the computed impact point so it should stay on the target ship. Takes time to do this and lots of practice.
This link has the method I use
http://www.subsim.com/radioroom/show...8&postcount=16
Always input the data in this order.
Turn on the PK and set speed and send to TDC
Next input AoB
Last range/bearing. Always last.
Check your firing solution on the attack map.
Magic
Edit, you posted as I was typing oh so slowly. I have two stupid fingers.
The problem with using the click for speed thing is you need two very good steadimeter readings about a minute or so for it to work, I never had much luck with it.
It's not cheating you gotta learn some how.