This kit contains SOD-123F, SSOP, and 0603 SMD parts. They are tiny, and the SSOPs have very fine pin spacing. Solder paste, hot air, and solder removal braid recommended.
There are a bunch of markers on the circuit board. C1, F1, R1, D1, U1, etc.
* C is for Capacitors, of which there are three. Two larger can style and one smaller ceramic.
* F is for Fuses, of which there are two. They have green markings.
* R are the resistors, those come in the longest strip (18 of them).
* D is Diodes, of which there are three.
* U is for the voltage regulator and Bus Switches. Fortunately they are easy to tell apart.
* J is for connectors, like the pin headers and MicroSD slot. (J is for ‘jack’, I suppose)
Always do the surface-mount components first. You won’t be able to install all the surface-mount parts if you do the through-hole things first. Make sure you install R3, R5, and R7 – they’re not in the same row as the other resistors.
Mind the orientation of some of these components. The black pill module, diodes, bus switches, and can capacitors must face the right way.
The fuses and resistors can be installed in either orientation or even upside-down (they are not directional). Be careful with the microSD slot, it’s a combination of metal and plastic and will melt if you heat it for too long with your heat gun.
Below are some renders from KiCAD showing the right way for diodes and chips to face. Note that the U2 and U3 chips will either have a dot indicating pin 1 as in the KiCAD render, or there will be a bar across the left edge. That bar indicates pin 1, and should go on the same end as the U2 / U3 silkscreen label.
Put the USB port of the black pill over the ‘USB’ marker (same side of the PCB where the microSD slot is). And install the SCSI port such that the notch lines up with the word ‘notch’ in the silkscreen.
Important Note: Please do install the four-pin right-angle connector on the black pill module. This is used for programming updated firmware later on. With the tall can-style capacitors you will need to bend the pins up about 15 degrees after soldering them down. See assembled picture below.
After installing the SMD parts, the remaining through-hole parts should be pretty straightforward.
Your fully assembled Desktop F4 BlueSCSI™ will look something like this.