ZPUSOB KALCINACE HYDROXIDU HLINITEHO

D.c. is passed from source (1) to d.c.-a.c. converter (3), passing a stabilised measuring current through terminals (4,5) to earthing element (6) and current electrode (7). Simultaneously the a.c. voltage from converter(3) passes to commutating filter (11) and sync. rectifier (12). Shaper (16) produces cut-off pulses, controlling the operation of electronic cut-off switch (8) and electronic switch (10). A mixt. of the active signal, noise voltage and internal tuning pulses passes from potential electrode (19) and element (6) to terminals (17, 18). - Switch (8) cuts off the tuning pulses with part of the active signal and noise and is then opened, passing the remaining part of the active signal and noise to filter (9). The mixt. is then passed through switch (10) to filter (11), where the active signal is accumulated and L.F. noise is suppressed. Rectifier (12) passes the rectified active signal and combined conversion freq. to rapid-action filter (13) and the active signal is passed through amplifier (14) to measuring instrument (15).