Recorders 

A recorder is a measuring instrument which records time varying quantity, even after the quantity or variable to be measured has stopped. The electrical quantities such as voltage & current are measured directly. The non- electrical quantities are recorded using indirect methods. The non- electrical quantities are first converted to their equivalent voltages or currents, using various transducers.

Electronic recorders may be classified as:

 1.       Analog recorders

2.       Digital recorders

Analog recorders dealing with analog systems can be classified as

 1.       Graphic recorders

 2.       Oscillographic recorders

 3.       Magnetic Tape recorders

 Digital recorders dealing with digital output can be classified as

 1.       Incremental digital recorders

 2.       Synchronous digital recorders