update on my new project

i havent posted anything regarding my new homemade NAS project since i mentioned it before. here are some updates to how it is coming along. to reiterate, here are the components used for this build:

1x raspberry pi 4b 4gb (will be swapped for 2gb variant in the future)
2x seagate backup plus slim 2tb hard drive
1x usb 3.0 4 port powered hub
1x 5v 5amp DC power supply
2x usb 3.0 male A to micro B male cable
1x usb type C male cable

- i decided that instead of gutting the seagate hard drives and using the holes on the drives as possible mounting points, i will keep the drive in its entirety instead. i ended up taping the two drives together with black electrical tape.

- went and purchased an AC cable for a standard atx power supply, and then wired it to the 5v 5amp DC power supply. tested good, so i cut end off of usb type C cable and wired to power supply, then wired usb 3.0 hub as well. both powered up.

- i took the hub and removed all usb connectors from the board. i tried my luck at soldering to the board. i managed to get one cable on, but the points were very small. i ended up trashing this board and had to purchase a new one. this hub, while similar in appearance to the one i trashed, was slightly different underneath the casing. it worked out because while it is slightly larger by a few mm on each side, the edge of the usb ports are flush with the board and didnt stick out. this worked out to my advantage as i could solder to the connector directly as the contacts were larger and easier to get to. removing the connectors wouldn't benefit me in terms of gaining space when mounting the components.

- i took two usb 3.0 male A to micro B male cable, cut the A ends off, and prepared the wires. usb 3.0 includes 2 extra pairs that provide the higher bandwidth throughput. both are wrapped in foil and are twisted separately from each other. i soldered both cables to the hub.

- if one hard drive was plugged in, the rPi would detect it and it would operate normally. however when both drives were plugged in, one of the drives would work and the other would not be recognized. didnt quite understand this so i searched around and posted about it on reddit.

- someone who responded suggested that the 2 extra pairs needed to be shielded to meet usb spec. he also suggested to keep these wires twisted as much as possible as they are impedence matched. so i only put foil on one pair of wires on one cable and tested. turns out this was the case and both drives were showing up now. i saved all of the foil i had stripped before and shielded the other wires.

so right now, the device is working, and now i need to figure out how i am going to build a small case for it. i would like to add a panel mounted AC recepticle so the power cable doesnt have to be attached at all times and is easy to remove. i would also like to extend the ethernet port to the back. i wish i had a 3d printer sometimes. before i put it in a case, i will probably resolder everything with all of the foil saved and the wires twisted closely to achieve the highest bandwidth possible.


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