Guide to file names.

##  Brighness  
The LED duty cycle is ramped 1 to 100 by steps of 1 to verify that the brightness increases linearly with duty cycle.  
Integration = 12 ms  
Averages = 5  
Files:  CWled1brightness.txt, ...2... ,  ...3...
note: integration at 5 ms resulted in unpredictable transients in the spectrum.  12 ms appears to be a minimum to guarantee stability with the admittedly unstable breadboard layout.  

##  Absorbance  
Absorbance is measured with the NIST standard.  
Integration = 50 ms  
Averages = 1 
LED duty cycle 18% (CW) 100% (WW) (max is just on scale in both cases)  
Files:  LED1_005.txt, etc.   
Files do not contain a wavelength axis. Wavelengths are provided in a separate file "wavelengths.txt".
  
##  Duty Cycle Frequency  
LED Duty cycle frequency is varied
Integration = 50 ms (CW)  50 ms (WW) {{CW has blue peak off scale}}  
Averages = 1
LED duty cycle 50 % (half on, half off)
Monitoring 590 nm (CW) 625 nm (WW)  
Files:  LED1_freq5_50.txt, etc.
The following intervals were used and correspond to file names.
5 to 50 Hz by steps of 5  
50 to 500 HZ by steps of 10  
500 to 5000 Hz by steps of 50