[Discuss-gnuradio] transmit gain

[njm25]

I am using the fm_tx4.py example to transmit using the Basic TX daughterboards. 
 I am getting about a 30mV peak-to-peak signal and I want to know if I can add 
more gain to the signal.  I don't know alot about this stuff.  I was thinking 
it might have to do with the line that says:

gain = gr.multiply_const_cc (4000.0 / options.nchannels)

but I don't know how much gain I can give it (if I just increase the number 
4000 or if this is not the way to do it).  Any help would be much appreciated.

Nick