Got my first Pico kit last week and the servo about drove me nuts

I picked up a similar kit a while back, mostly because the organizer box was convenient for my desk drawer. The board itself has been rock solid, but fair warning on the jumper wires in mine, a few of the female ends were loose and I chased what I thought was a flaky sensor for two evenings before I figured out the wire was the problem. A quick multimeter check on each lead saved me a lot of head scratching after that. The little display was the fun part for me too. Mine needed a third party library beyond what the tutorial PDF covered, and I found the example code on the manufacturer's GitHub page rather than the included docs. Worth checking there if the screen acts stubborn out of the box. On the servo, I had the exact same twitching problem until someone in a hobby group told me the same thing about powering it separately and tying the grounds together. Once I moved it to a 4xAA pack the jitter vanished completely. I also learned to add a big capacitor across the servo supply, since the motor spikes were browning out my board mid motion. If you do the temperature sensor mashup, try logging the readings to a file on the board and pulling them over USB. It turned my little weather demo into something I actually check every morning.

Funny enough my kit experiance went the opposite way with the tutorials. The little walkthrough book sat untouched after the first session. What got me actually learning was picking tiny goals and googling each one, like making the buzzer play a tune, or reading a potentiometer to dim an LED. The bundled lessons tend to stop right where things get interesting, so I stopped waiting for them to catch up with what I wanted to build.

The sensor grab bag was hit and miss too. My humidity sensor was fine but the ultrasonic one gave nonsense untill I noticed the pin labels printed on its back board didn't match the wiring diagram in the docs. Ever since I go by the chip markings rather than whatever silkscreen the kit maker put on. One thing I found handy, the Pico has a temperture sensor built into the chip itself, so you can get a working readout on your laptop with nothing but a USB cable before you even open the breadboard bag. Made a nice first win when my kit's extras felt intimidating.

On the servo side, my cheap SG90 clone buzzes a bit even when it has nothing to move, no matter how I power it. Some of those little motors are just noisy, so if yours still twitches after fixing the power situation it might be the servo and not you.

I'm skeptical about needing a big capacitor across the servo power like you mentioned. While those motor spikes are real, I found that if you use a robust power source, like the 4xAA pack you mentioned, the onboard power delivery is actually sufficient. I ran a few similar setups without adding any external capacitors, and I didn't see any brownouts or performance drops, so maybe the spikes are exaggerated in cheaper kits. It just seems like an extra step unless the power supply is actually terrible.

Update: went back and wiggled every jumper end in my kit after reading the first reply here, and two of mine were loose too. Swapped them before they cost me a mystery evening like that. Also tried the small goals approach with the buzzer, got a rough tune out of it. New question though, is a bit of faint ghosting on the little screen normal, or is mine a dud?