R2 and Back Row Attack - Whistle?

[timasdf]

2014 Case Book 5-5-3b-7 says, "The second referee's specific responsibilities shall be to determine back-row player faults."

Specifically, what does "determine" mean? Give discrete signal to R1? Blow the whistle to stop play?

I seem to recall some conversation at a local meeting about the R2 being mandated to blow the whistle in this situation, but I don't see this specifically in the Rule or Case Book.

Based purely on the Case Book 5-5-3b, I would say, discrete signal only. That is because 5-5-3b-1 says, "Whistle and give the signal for calls initiated by the second referee including time-out, substitutions and dead ball out of bounds for an antenna fault on second referee's side of the net." Is there a difference between "Whistle" and "Determine"?

Thanks,
Tim