Chapter 2 Command System  RIGOL 
DG800 Programming Guide  2-107 
Remarks   
  This command is only applicable to the internal modulation source 
(
[:SOURce[<n>]][:MOD]:FSKey:SOURce). The FSK modulation rate refers to the frequency at which 
the output frequency "shifts" between the carrier frequency and the hop frequency 
(
[:SOURce[<n>]][:MOD]:FSKey[:FREQuency]). 
  When [:SOURce[<n>]] or [<n>] is omitted, the system sets the related parameters of CH1 by default. 
 
Return Format 
The query returns the FSK modulation rate in scientific notation, with 7 effective digits. For example, 
1.500000E+02 (the FSK modulation rate is 150 Hz). 
 
Example   
:SOUR1:FSK:INT:RATE 150       /*Sets the FSK modulation rate of CH1 to 150 Hz.*/ 
:SOUR1:FSK:INT:RATE?       /*Queries the FSK modulation rate of CH1 and the query returns 
1.500000E+02.*/ 
 
 
[:SOURce[<n>]][:MOD]:FSKey:POLarity 
 
Syntax 
[:SOURce[<n>]][:MOD]:FSKey:POLarity {POSitive|NEGative} 
[:SOURce[<n>]][:MOD]:FSKey:POLarity? 
 
Description   
Sets the FSK modulation polarity of the specified channel to Positive (POSitive) or Negative (NEGative). 
Queries the FSK modulation polarity of the specified channel. 
 
Parameter 
 
Remarks   
  When [:SOURce[<n>]] or [<n>] is omitted, the system sets the related parameters of CH1 by default. 
  In the internal modulation (
[:SOURce[<n>]][:MOD]:FSKey:SOURce), set the polarity to "Positive", 
and the generator will output the carrier frequency when the modulating waveform amplitude is a logic 
low level. It will output the hop frequency (
[:SOURce[<n>]][:MOD]:FSKey[:FREQuency]) when the 
modulating waveform amplitude is a logic high level. The situation is the opposite when the polarity is 
set to "Negative". 
  In the external modulation (
[:SOURce[<n>]][:MOD]:FSKey:SOURce), set the polarity to "Positive", 
and the generator will output the carrier frequency when the external input signal is a logic low level. 
It will output the hop frequency (
[:SOURce[<n>]][:MOD]:FSKey[:FREQuency]) when the external 
input signal is a logic high level. The situation is the opposite when the polarity is set to "Negative". 
 
Return Format 
The query returns POS or NEG. 
 
Example 
:SOUR1:FSK:POL POS    /*Sets the FSK modulation polarity of CH1 to Positive.*/ 
:SOUR1:FSK:POL?        /*Queries the FSK modulation polarity of CH1 and the query returns POS.*/