This circuit indicates when a rain is acidic by monitoring its pH. The circuit is from a 90s RE Experimenter Handbook. Some components used can be difficult to obtain today.
This common emitter amplifier with 43 dB gain was found in the August 1970 issue of Radio...
This circuit was found in a technical documentation from Texas Instruments, using a...
We found this circuit in a 1980 publication. It can be applied to Triacs of the TIC series and the...