modes.txt

# $Id$
# Mode definitions for KA9Q software receiver - Oct 2017

# Name - name of mode
# Demod - Demodulator thread: FM or LINEAR
#    FM - frequency demodulation by complex arctangent, with suppression of weak samples for threshold extension
#    AM - amplitude demodulation by envelope detection
#    LINEAR - everything else: CW/SSB, coherent AM, DSB/BPSK, ISB (can also do envelope detection)

# Filter high and low - digital IF bandpass filter frequency limits
# Offset - frequency shift applied *after* filtering; carrier, normally at zero, will come out at specified offset; N/A to FM and envelope detection
# AGC attack - AGC attack rate, dB/s (negative); N/A to FM
# AGC recovery - AGC recovery rate, dB/s (positive); N/A to FM
# agc hang - AGC hang time before recovery, sec; N/A to FM

# flags:
#    flat - bypass de-emphasis and PL tone removal (FM only)
#    conj - cross-combine the complex conjugates of the upper and lower sidebands - for ISB (independent sideband) (linear only)
#    mono - send only I channel as mono; otherwise stereo with I on left and Q on right (linear only, others are inherently mono)
#    pll - Acquire and coherently track carrier; without "square", uses conventional PLL (linear only)
#    square - square signal before coherent tracking (for suppressed carrier DSB and BPSK) (linear only)
#    cal - special calibrate mode for WWV/CHU: adjusts TCXO offset to bring measured carrier offset to zero (implies pll) (linear only)

#  Name      Demod     Filter low    Filter high   Offset  agc attack    agc recovery     agc hang     headroom	     flags      comments
# bandwidth symmetric modes
FM           FM         -8000          +8000          0        0 	       0	   0.01		0			# standard NBFM (PM) -6dB/oct de-emphasis, PL removal
AM           LINEAR     -5000          +5000          0      -50	      +50          0.01        -15	  env        	# standard AM envelope detection
CAM	     LINEAR	-5000	       +5000	      0      -50              +50	   0.01	       -15	  pll		# Coherently track carrier (AM, low mod PM)
DSB	     LINEAR	-5000	       +5000          0      -50              +6           1.1         -15	  square        # Square to regenerate suppressed carrier
IQ           LINEAR     -5000          +5000          0	     -50              +6           1.1         -15	  stereo	# Left = I, Right = Q, no tracking
ISB          LINEAR     -5000          +5000          0	     -50	      +6           1.1         -15	  stereo conj	# add/subtract conjugates of +/- freqs
CISB         LINEAR     -5000          +5000          0	     -50	      +6           1.1         -15	  stereo pll conj 	# is there such a thing?

# Bandwidth asymmetric (SSB/VSB) modes
CWU          LINEAR      -200           +200       +700      -50              +20	   0.2         -15			# dial freq is for +700 Hz tone
CWL          LINEAR      -200           +200       -700      -50	      +20          0.2	       -15	   	  	# dial freq is for -700 Hz tone
USB          LINEAR      +100          +3000          0      -50	      +6           1.1	       -15	  
LSB          LINEAR     -3000           -100          0      -50	      +6           1.1	       -15	  
AME	     LINEAR	    0	       +3000          0      -50              +15          0.01        -15	  pll		# enhanced (full carrier) USB AM for CHU