These are the assembly instructions for the F4Lite Desktop THT V1.1 kit.
Please read all the instructions before assembly, to ensure things end up in the correct positions.
The very first thing to install is the SCSI connector – it is far harder to install later on. This looks potentially hard, but the PCB comes with a little hook to grab the side of the connector right where it needs to go. Put the diodes underneath the PCB where the SD card slot is, with SCSI port in position, and that holds things at just about the right height. Make sure the notch is on the side labeled “Notch”.
The next important things are resistors. You will notice there are different sizes, this was done to ease assembly. The smaller resistor is R2. There are two larger resistors, and here is how you can tell them apart. The resistor to put in position R1 has its yellow stripe in the middle of the resistor. Picture for clarity:
Take care to align your voltage regulator (U1) such that the hole is lined up with the PCB hole. This is for a mounting screw, to hold the regulator in place against the PCB where there is a heat dissipation pad and area. A mounting hole is located here on the included bracket.
Next, check the orientation of the diodes. Stripe-side faces the fuse (F1, round tan disc).
The termination resistor packs can optionally be hard-soldered in place (always on), but it’s better to use the little black socket strips (note: these are just a DIP-20 socket snipped in half). I like to solder the sockets with the cut parts facing the pill module (blue pill, black pill, or green pill) but that’s up to you.
Please ensure that you install the green module with the USB port over the “USB” marking on the PCB. Installing the other way will make your device not function.
The only other important thing is the termination resistor packs. Those must be installed as follows :
* In position RN1, the text on the resistor pack faces the SCSI port
* In position RN2, the text on the resistor pack faces *away from* the SCSI port
Be sure you solder on the USE_TPWR header (or hard-wire it with some scrap component leads like excess from the resistors) if you intend to run from SCSI termination power.
Your LED resistor goes in position R3. You can either use the included 2.54mm header for your LED plug, or solder directly onto the LED wires.
Over on the other end of the board, this is how the diode, fuse, and LED resistor are placed. Note the LED resistor has a yellow stripe at the edge. The other larger resistor with yellow stripe in the middle goes by component marked U1.