- Published in issue 7/1992 on page 63
Audible fluid level indicator
A 600 Hz signal at a level of 2.4 Vpp generated by the oscillator on board an LM1830 (NationalSemiconductor) is applied to a probe via C2. The probe is immersed in the liquid whose levelistobe monitored. Because of C2, there is no direct voltage at the probe. so that there are no electrolysis problems.