OK so there was a commlink we need to find and to was in an upstairs room in a crowded bar. So I am wonder what I would need to do to find it if it was active and also if it was in hidden mode?

as per the BBB p.225:

"Locating a particular active or passive wireless node within range (or all of them, for that matter) takes only a Free Action, no test required."

and

"Finding a wireless node in hidden mode (see p. 211), however, is more challenging. Even if you know what you’re looking for, you must still succeed in an Electronic Warfare + Scan (4) Test. If you’re just scanning for hidden nodes in general, or trying to pick the hidden nodes out from the non-hidden one, make the same Extended Test noted above but with a much higher threshold: 15+."

Basically I am not sure when which rule to use. Since it was upstair in an uncrowded area by itself would be easy and I could look for a particular node or do I need to do the extended test and pick it out from hidden and nonhidden.

If it's active and you know which node you're looking for you just grab it with a free action. If it's hidden you have to do the EW + Scan test.

What if, for example you don't know what node you are looking for but you know it's within range. This happened in the last session I ran. The players were in a bar and they knew the person who they were looking for was there, but didn't have his commcode or anything. To look for him, the hacker started scanning nodes (The guy they were looking for did has his active). But since he didn't know exactly what he was looking for I ruled that it was something similar to finding a hidden node, just not as hard. So I had him roll Scan + Electronic Warfare extended test, but with a low thresh hold.

the way i interpret it, if someone has there commlink on active then they are broadcasting data such as their profile, SIN, etc. so it should be pretty easy to find (hence the free action)

afterall if they are in active mode, then they are interested in being found.

That's a good point. I guess I didn't consider all the information an active node is broadcasting. To me (as someone who actually works in computer programming and security) I find the thought of broadcasting anything like that silly but then again, I'm not the average Joe. Also, I agree data search would have been a better choice.

ok here we go:
p.220 BBB
"In some cases, Data Search actions may be handled using other programs. If you wanted to pick out a particular person’s PAN in a crowded club, for example, you’d roll Data Search + Scan program."

So to clarify,
active comm alone= free action
active comm in crowd= data search
hidden comm in crowd= EW
Any thing else?