Need help identifying components! Hardware
Third one looks like a &quot;Phoenix&quot; style 3.81mm pitch connector (it's been slightly mangled by something). There are several manufacturers for these parts, you don't need to go with the ones from &quot;Phoenix contact&quot; To fit this connector the matrix board would have needed extra holes drilled or the pins would need to be bent, (pins 1 and 3 line up with holes, but pins 2 and 4 will be half-way between holes) or install it rotated 45 degrees.
Second one looks like a &quot;USB charger power module&quot;: presumably it makes 5V to run the Adiuino and the Raspberry pi. presumable of of those XL801
The top one is also some sort of DC-DC converter  &quot;HENGE UBEC 8A/12A peak&quot;
REG1,REG2,REG3,REG4 in the diagram