Un Q-metre adapte a la mesure de polarisations nucleaires elevees

A Q-metre circuit specially designed for the measurement of high nuclear polarizations is described. An audio-frequency feed-back circuit operates on the amplitude of the generator feeding the Q-metre and it is shown that the output voltage can be made proportional to the changes of the admittance Y...
Ausführliche Beschreibung

A Q-metre circuit specially designed for the measurement of high nuclear polarizations is described. An audio-frequency feed-back circuit operates on the amplitude of the generator feeding the Q-metre and it is shown that the output voltage can be made proportional to the changes of the admittance Y = Z^-^1 of the circuit. The result is that the resonance signal, instead of being of the form X''/(1 + X'') as usual, is very nearly proportional to X''; X'' = 4πνQξ'' is proportional to the dissipative part oof the high frequency susceptibility. Detailed circuit diagrams are given; the operation of the circuit has been tested by experiment. Ausführliche Beschreibung