This DIY kit will help with your soldering skills, while you learn about the standard 358 opamp IC. The kit teaches you how the IC can be used to get a sensor to switch a relay ON at an adjustable set point. Where you have the choice of an NTC or LDR sensor as an input device. It intergrades a voltage-follower NPN transistor and Zenner as a stable voltage regulator. So you can power it with a wide voltage range and no need to worry about the voltage varying on the ref point of the opamp.
This universal sensor board can be set up as a daylight switch or Temp switch
by only using an LDR or NTC as our sensor for the application this will switch a Relay on at a set value selected using a pot.
We also have a Uni Sensor PCB project with more information.
Universal Sensor Specification:
Capacitors Values: 330uF, 220uF, 100uF
Resistors Values: 10k, 1K, 220R, 10k
Variable Resistor Values: 100K
Diodes: 2x 1N4001 Diodes, 5V1 zener
Transistors: NPN TIP 120, BC337
Relay: 5V Relay
Connectors: 2x 2Pin, 1x 3Pin
LEDs: 1x 5mm LED red
Sensor IC: LM358 Sensor IC