| Crystal radio receiver v2 |
Radio receiver without power supply. |
| Darkness detector |
Darkness detector with photo resistor and NE555. |
| GSM phone ring detection |
This device will blink LED just before GSM phone will ring. |
| GSM sniffer |
Locate a GSM phone. |
| Heat detector using NE555 and diode |
Heat detector using NE555 and a diode. |
| Lie detector v1 |
Very simple lie detector. |
| Metal detector |
Another metal detector. |
| Rain detector |
Rain or water detector. |
| Short circuit detector |
Detects open and short circuit conditions. |
