Scope and object
The test procedures of this International Standard cover
amplifier and preamplifier systems with linear pulse shaping
networks for use with semiconductor, scintillation and proportional
detectors in the spectrometry of ionizing radiation. The object is
to provide a common language and methodology for users and
manufacturers of pulse-amplifier systems.
Test procedures for associated detectors are described in IEC
333 and IEC 973.
Not all of the tests described in this standard are mandatory,
but those that are performed to determine preamplifier and
amplifier specifications shall conform to this standard.
The emphasis on the methods of measurement is to enhance
sensitivity and improve accuracy by working around the limitations
of the test instruments, particularly oscilloscopes which have only
a visual display for read-out. A null technique is used where
possible, thereby reducing basic errors to the inaccuracy of a pair
of precision resistors. When use of a bridge is inappropriate, such
as in measurements of pulse height with an oscilloscope, the pulse
is made to occupy a fixed amplitude and vertical position on the
face of the cathode ray tube. Some measurements require test
instruments or fixtures not commercially available at this writing;
circuit diagrams for their construction are given in the annexes.
The use of a standard nuclear instrument module to test the
performance of an amplifier is not acceptable unless the errors
introduced by that module can be corrected for or shown to be less
than the error caused by the amplifier. Examples are the use of a
crossover pickoff module to measure crossover walk in a bipolar
amplifier and an MCA to measure nonlinearity and noise.