**********************************************************************
probeConnect (P) - set the nuclei tuned on the probe ports connected to 
                   each transmitter channel
preAmpConfig (P) - set the band of the preamp, high or low, connected to 
                   each transmitter channel.  

nm1 (M) - returns the current transmitter corresponding to the nucleus 
          in argument 1. 
***********************************************************************

  probeConnect - sets the nuclei tuned on the probe ports connected to 
     each transmitter channel. This global parameter is a string whose 
     entry is a list of nuclei separated by spaces. The number of nuclei
     must equal the number of channels, numrfch and no two nuclei can be
     the same. The nuclei from left to right refer to the transmitter
     channels "1","2","3".. etc, which for VNMRS correspond to preamps or
     RF cable outputs from the Front End and from the transmitters in the
     RF card cage, right to left. 
  
  preAmpConfig - sets the band of the preamp, high or low, connected to 
     each transmitter channel. This global parameter is a string whose 
     entries are the characters "H" "L" and"X" separated by commas.  The 
     number of characters must equal the number of channels, numrfch. The 
     characters from left to right refer to the transmitter channels
     "1","2","3".. etc, which for VNMRS correspond to preamps or RF cable 
     outputs from the Front End and fom the transmitters in the RF card 
     cage, right to left. Set: 'H' for a highband preamp, 'L' for a 
     lowband preamp and 'X' for no preamp. 
   
  nm1 - returns the transmitter corresponding to the nucleus in argument 
     1. nm1 is used to set the channel number for obs, dec, dec2 and dec3 
     on the Channels screen of the Acquisition Page. If probeConnect and 
     preAmpConfig are present they are used. Otherwise if rfchannel is
     present,it is used or if rfchannel is not present the defaults are set. 

  probeConnect and preAmpConfig are required for all experiments that use 
  transmitters "3" and "4" as Obs or Dec.   Create probeConnect and 
  preAmpConfig as global parameters on the commandline with: 

     create('probeConnect','string','global')
     create('preAmpConfig','string','global')

  If probeConnect is present it will overide the transmitter settings in 
  the 'current' parameter rfchannel. 

  If probeConnect and preAmpconfig are not created and rfchannel is not
  present the default transmitters are: 

     Obs (highband) "1" Dec (lowband) "2" 
     Obs (lowband) "2"  Dec (highband "1" 
     Dec2 (highband or lowband) "3"
     Dec3 (highband or lowband) "4" 

  If probeConnect and preAmpconfig are not created the default preamps are
  presumed to be:

     "1" highband 
     "2" lowband
     "3" lowband 
     "4" lowband 

  probeConnect and preAmpConfig must both exist or both be absent. 
  If they exist both must have correct values.  An empty string or incorrect
  string in either parameter will cause errors in channel selection. 

  Examples: 

  ProbeConnect = 'H1 C13 F19 N15', PreAmpConfig = 'HLHL', numrfch = 4,
  tn = 'H1', dn = 'C13', dn2 = 'N15' causes: 

      Obs on channel "1"
      Dec on channel "2" 
      Dec2 on channel "4"

  ProbeConnect = 'H1 N15 F19 C13', PreAmpConfig = 'HLHL', numrfch = 4, 
  tn = 'H1', dn = 'C13', dn2 = 'N15' causes: 

      Obs on channel "1"
      Dec on channel "4" 
      Dec2 on channel "2"

  ProbeConnect = 'H1 N15 F19 C13', PreAmpConfig = 'HLHL', numrfch = 4, 
  tn = 'C13',dn = 'H1', dn2 = 'N15' causes: 

      Obs on channel "2"            
      Dec on channel "1"
      Dec2 on channel "4"

  


      



  


