Please bear with me since am a noob in electronics. I made a relay module based on internet DIY tutorials. It turns on when I provide 5V from adapter to both +5V and signal but when I supply high of NodeMCU to signal pin it doesn't work. Any suggestions what is wrong with module I created?
Also want to check if this sketch is using optocoupler correctly. I have no clue :(
Relay used usedhttps://sharvielectronics.com/product/spdt-5v-30a-relay-pcb-mount/