-------------------------------------------------------------------------
A Wiring Diagram for SDtask sdcal
-------------------------------------------------------------------------

		sd.scantable  <--- infile, scanaverage

		    |
		    V

		set_fluxunit  <--- fluxunit, telescope
                convert_flux  

		    |
		    V

                set_unit      <--- specunit

		    |
		    V

                set_freqframe <--- frame

		    |
		    V

		set_doppler   <--- doppler

		    |
		    V

                selector      <--- scanlist, iflist, field

		    |
		    V

		calibrate     <--- calmode

		    |
		    V

		opacity       <--- tau

		    |
		    V

                average_time  <--- timeaverage

		    |
		    V

		average_pol   <--- polaverage

		    |
		    V

                 smooth       <--- kernel, kwidth

		    |
		    V

                baseline      <--- blmode, blpoly
                                   masklist, interactive
		    |
		    V

		  save        <--- sdfile, outform