Soldering a usb wifi module to a raspberry pi zero's test points

I'm sure I found instructions on how to solder a USB wifi module onto a Raspberry Pi Zero somewhere. After seeing that, I bought a couple of little USB modules:


Described as RT3070 Ralink Network Card Adapter Module. It works plugged into the Pi's USB port without any problem, so that's a start.

Here are the instructions. I was under the mistaken impression you get an extra port out of it, but you don't - you are just using the one usb port.

I'm going to cut the cable and use the existing wires. I've got another module, and another cable for testing, if that's needed. They are:

  • red: +5V -> PP1
  • yellow: D- -> PP23
  • white: D+ -> PP22
  • green: ground -> PP6

There's a spreadsheet of test points here.

I actually got the D+ and D- the wrong way round the first time, because I found a misleading description of the module, but nothing got broken, and it worked at the second attempt. The order is just as you would expect for a USB connector (which the module has solder pads for).

I didn't want to just leave the module dangling unprotected, so I made a little cover, the the module clips into:

Amazingly, my little pcb holders worked first time, however the fit was a little too tight for the raspberry pi. Also, I made the holes for the screws too small. I made these adjustments, but none of the subsequent prints worked: the pcb holders printed too big to push the pcb on to.

Anyway, I adjusted the first one with a knife, and got the pi zero to go in:

Of course, there's the pi-zero W now, which I found out about just after I bought the two modules, so I'll just buy those from now on, but this is a neat way to attach wi-fi to my older pi-zeros.


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