Review on 👾 kuman Raspberry Pi 4B/3 Arduino Starter Kit with LCD Screen Module Breadboard – Ideal for Pro Mini Atmega Mega Robot K64 Projects! by Bradley Wacks

I hooked up an LCD and used two potentiometers to control the contrast and brightness. I've seen someone say that you have to buy other things to use them, but that's not the case. Just plug them into the breadboard and route the wires where they need to be. The bad thing I will say about potentiometers is that they are really very sensitive. After all, there was a small adjustment window for the contrast and brightness of the screen, but the rotary knob turned much further. They still worked for me but might not work for you. I tested several buttons and all worked. A few LEDs I tried worked just as well as the included resistors. I haven't measured them, but different resistances give different results with LEDs. Nothing I tried in the kit was DOA so that's always nice. It should be noted that you will need to solder the pins to the LCD screen. If you don't solder them you will almost certainly get bad contact with the screen no matter how hard you try. I've seen many complaints on various forums about this. People spent hours trying to figure out a mysterious issue causing the screen not to work when it all boiled down to a bad connection.