function [y,fs]=bandsig(fc1,fc2,L)
%	  [y,fs]=bandsig(fc1,fc2,L)
% create a random bandpass signal with frequencies fc1 to fc2
% where fc2 < 2500.
% Sampling frequency is fs=6000 Hz, and signal duration is L/fs seconds.
	fs=6000;
	x=randn(1,L);
	b=1;a=1;
	if fc1==0 & fc2 < .5*fs
		[b,a]=butter(8,(2/fs)*fc2);
	end
	if fc1>0 & fc2<.5*fs
		[b,a]=butter(4,(2/fs)*[fc1,fc2]);
	end
	if fc1>0 & fc2 >.49*fs
		[b,a]=butter(4,(2/fs)*fc1,'high');
	end		
	y=filter(b,a,x);