The HV2405E integrated circuit is not very common these days. This circuit was found in the August 1998 issue of Electronics Now magazine. The current is a few tens of milliamps.
For the 600 kHz range coil is formed by 35 turns of 28 AWG wire on a ferrite core with a diameter...
Found in a 1970’s documentation, this circuit uses components of the time, uncommon today. |...
This 2003 circuit uses two types of sensors: by reed-switch and by infrared. If the magnetic...