The anti-contamination circuit of the Amsterdam isotope separator. II

In a previous article the task of the circuit for preventing contamination of the collected isotopes in an electromagnetic isotope separator has been indicated. In this article the electronic realization is described in detail. a. The circuit is operated by the difference of the currents on two needle electrodes in the beam, operating a small servomotor to correct the accelerating voltage until the beam reassumes the correct position (beam shifting control);b. the total current on these electrodes is compared with an adjustable reference current, and when the difference between these two currents exceeds a certain value, a cover is closed before the collector (intensity control);c. The current on a diaphragm before the collector is integrated over periods of 30 s. At too large a value of this time integral the cover is also closed.