Recording of Signal Current

In general, the signal from a gas chromatograph is recorded continuously as a function of time by means of a potentiometric device. Most frequently, a recorder of 1-10 mV full-scale deflection ( 10 inches) and having a response time 1 second or less is quite adequate. 

Variable chart speeds between the range of 5-50 mm. min-1 are most preferable in GC. 

The following important points should be noted before operating a recorder, namely  

An intergrator may be regarded as a device that essentially facilitates simultaneous measurement of areas under the chromatographic peaks in the chromatogram either by mechanical or electronic means. It is, however, pertinent to mention here that manual techniques for determining peak areas are known, such as  

There are two types of integrators generally employed in GC, namely  

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