This is quick post to show how you can choose and write an Operating System to a SD card for use on a Raspberry PI computer.

Raspberry PI

A Raspberry Pi is a wonderful 5V mini computer that you can use in IoT projects, Programming, Retro Gaming  or as a desktop replacement.

View all Raspberry Pi computers here:

All Raspberry Pi Boards at

The Raspberry Pi has an official Operating system called Raspian.

Raspian LOgo

Many other 3rd party Operations system exist

all 3rd party operating systems

Raspian comes with a Windows like desktop that you can use.

Raspberry PI Desktop

You can even install a Retro Pi image to allow you to play old arcade and Console games in an emulator.

Raspberry Pi Zero W

For this post I will be using the older Raspberry Pi Zero W to setup an operating system.

Raspberry Pi Zero W with all plugs plugged in

I have a few Raspberry PI Zero W’s  (v1.1) laying around

Closer look at one of them

Raspberry Pi Zero W with all plugs plugged in (angle 2)

It’s only has 1x CPU  Core and 512MB of memory. It had Micro USM keyboard and power in plugs.

Micro USB PLugs

I have added a small eBay heat sink to the CPU to help limit thermal throttling when the CPU is working hard.

CPU Heatsink Attached

The good thing about the Raspberry Pi is you can add a fan from the supplied 5V pin.  Read more about available pin’s here: or here

Raspberry Pi Fan

Obviously I would mount it better than this when I turn it on.

You can buy inexpensive drop on references boards to help remind ytou of each pin.

Pi Pin Reference board

The reference board just pops over the pins

Pi reference board

Please visit this page to compare all Raspberry Pi Model Specifications:

Raspberry Pi Specs

SD Card (Required)

The Raspberry Pi does not have a Hard Drive (Magnetic, SSD or NVME) and you will need a Micro SD card. An operating system will need to be written to the SD card and inserted into the MicroSD slot on the Raspberry Pi.

Raspberry Pi Micro SD Slot

I would not put a cheap/slow MicroSD card in the Raspberry PI, aim for a UHS (1) or UHS (3) speed SD card for best bang for buck.

SD card speeds

Make sure you SD card is not write protected (if it is inserted into an old SD card adapter). My computer does not have a MicroSD card slot.

I have 2x SD card adopters that my MicroSD card inserts into.  Then the SD card inserts into my PC.

Make sure the write lock is not on.

SD Card write lock

SD Image Writing Software

I want to setup a new Pi for use as a PiHole Ad Blocker on  my home network. Screenhshot

I can see the PiHole software needs Rasbian Operating System on the Raspberry Pi (ARM CPU)

Pi Hope Supported OS page

Now that I know what Operating System I need to install I need to grab the SD Imager software from

I downloaded the software and open it to install it.

I clicked Install

Raspberri PI Imager install screen

I clicked Next

After the software was installed I clicked Finish to open the software

In the background I formatted (as FAT32)  my 32GB MicroSD Card (that was in the SD card adapter).

I will not do a quick format so every sector on the card is tested and formatted.

Windows Format screen

This may take 30 minutes to format buy it is worth while.  I don’t want a bad SD card making its way to the Raspberry PI.

Windows format in progress.

Format comlplete

Format complete

Open the Raspberry Pi Imager program that you installed earlier.

I clicked “CHOOSE OS

Raspberry Pi Imager Program

I can choose an operating system to download and write to the SD card

Imager Operating system choices

I chose “Raspian (other)” then “Raspian Full

Raspian Full Install

Raspian is now the selected operating system

Raspian Selected

I clicked “CHOOSE SD CARD” and selected my 32GB SD card.

Choose SD card dialog

The Operating System and SD Card have been selected

OS and SD card selected

I clicked “WRITE” and within 5 seconds noticed my WiFi was download  the Operating System, Nice.

Raspian Full Downloading via WIFI and writing to the SD card.

The write process will take at least 30 minutes (depending on your internet speed).

The Imager is verifying the SD card

When it’s complete a Verify will be performed and hopefully will have a SD card ready for use in a Raspberry Pi computer.

The write completed and files are on the SD card.

Write Verify Complete

I will prepare 3x MicroSD cards I have ready for My PiHole adventures. Blog post coming.

The post How to use the Raspberry Pi Imager to download an Operating System to an SD card ready to use with your Raspberry Pi appeared first on IoT, Code, Security and Server Stuff.