This circuit is a Magnet polarity detector using hall effect sensor IC W277.
Parts List:
IC W277
Transistor 2N3906 (SMD A2) or any other PNP transistor (2pcs)
Common cathode 7-segment display
Resistor 1K (2pcs)
Resistor 10K (2pcs)
Resistor 330 ohm
Reed switch (normally open)
3V Coin cell Battery with holder
Circuit:
You can order this PCB from PCBWay.com:
https://www.tinkercad.com/things/f2PPsV2GhBA
https://www.tinkercad.com/things/1Ai50KVamzV
Video:
