Question

Which of the following is not the characteristic of chopper amplifier pH meter?

(a) Direct voltage from the electrodes is chopped at the main frequency

(b) Using choppers for high-input resistance gives rise to spikes of waveforms at the output

(c) It leads to stability in DC output of phase-sensitive rectifier

(d) Magnitude of surge increases in the glass electrode output

The question was asked in homework.

Query is from pH Meters topic in section pH Meters and Ion Analysers of Analytical Instrumentation

Answer 1

Correct option is (c) It leads to stability in DC output of phase-sensitive rectifier

For explanation I would say: The use of chopper amplifier in pH meter leads to zero instability. It leads to various other problems for high-input resistance.