Ad-Blocking On The Go

WireGuard Logo

After a recent trip away and having to endure the torrent of adverts and tracking that hotel WiFi and mobile internet connections provide, I was definitely missing the ad-blocking features of my Raspberry Pi running Pi-Hole back at home.

I’d also been thinking for a while that I should do something about securing my phone a little bit from the risks associated with using an unencrypted WiFi connection like the one available to me at work. Using insecure WiFi is a bad idea because anyone else on the same network can examine your traffic and potentially log in to all your internet accounts by stealing session cookies and account details.

So, I decided to add PiVPN to my Raspberry Pi and Pi-Hole setup. Now when I’m away from home, my phone encrypts all of its traffic using WireGuard and sends it back home to my Rasberry Pi. Here, all the usual blocking of adverts and trackers happens and I get the same nice experience out and about as I do at home. There’s also the added peace of mind that means nobody on an insecure WiFi link can see the traffic between my phone and the internet any more – everything is encrypted on its way back to my house. Lovely.

PiVPN was a breeze to set up. It took just seconds to install and set it up, and adding the phone’s connection was as simple as pointing my phone at a QR code. Amazing work by the community.

Fighting Back Against Internet Advertisements

PiHole Dashboard

I’m old enough to remember the World Wide Web in its infancy in the early 1990s, when the focus was on information sharing. These days the main aim of the web seems to be to make money by tracking people’s habits and showing them adverts.

I missed the old experience, and I wanted some protection against being tracked everywhere online, so I installed Pi-Hole on a Raspberry Pi and tucked it away behind the sofa. It was very easy to set up, and has worked perfectly for over a year, protecting all of our devices from the spying panopticon of advertisers.

I have genuinely been surprised at just how much of modern internet traffic is related to tracking and adverts. In fact, my Pi-Hole has blocked more than half of the total requests for data! That’s right – there’s more stuff flying around for the adverts and trackers rather than the actual content that you see. Crazy.

With Pi-Hole blocking things silently, you end up with cleaner web pages without the clutter of adverts, and pages load noticeably faster when they aren’t reporting back to big brother too. Mobile apps and games no longer show annoying full-screen adverts and things just work much much better.

In fact, Pi-Hole blocking has been so good that as soon as I go out and about away from my home network it is very jarring to see the internet as everyone else sees it. Full of adverts and junk. Yuck. I do have a plan to fix that little problem soon though…

SDR Trouble

USB SDR RX

One of my colleagues asked me to have a look at receiver that wasn’t behaving well. It was one of the many USB receivers that are around based on the RTL 2832U and Rafael Micro R820T tuner chips. The device was very intermittent, but he wasn’t sure if it was a problem with the hardware, or with the software (and drivers) on his Windows PC. I don’t run Windows myself, so would be able to easily rule that out as a potential problem.

On connecting the device up to my Linux machine, it appeared to be behaving itself and showed up listed as a DVB-T device when I typed ‘lsusb’ into my terminal. However, when trying to actually use the device, it returned lots of errors before disappearing from the USB bus. Re-plugging it would make it come back to life again.

In my experience, complex microprocessor based things generally either work or they don’t. So to see a device that would speak happily over USB but fall over when used was a bit odd. What might cause something to misbehave in this way?

Thankfully my first hunch was correct. I swapped the rather long and thin USB cable for a short fat one. Hey presto – the device behaved perfectly and I left it running for a few hours without any issues. The resistance in the original cable, combined with the high current draw by the receiver was causing the voltages to drop, interfering with the normal operation of the device.

So, it’s always worth trying different cables when troubleshooting something, even if (as in this case) the original cable appears to be doing its job.

A New Lease of Life

I changed jobs about 18 months ago, and I’m already getting known as ‘that’ guy when it comes to fiddling with technology!

So, a colleague turned up at work with a laptop which had been given to him by a family member, after they’d bought a newer machine. He said it was running slowly and asked me if I’d have a look.

It seemed reasonably modern, probably about 7 or 8 years old. However it was running Windows 7, which I don’t really know my way around too well having not used Windows myself since the days of Windows 98 and Windows XP.

I was able to find out enough information to establish that the machine was slow because the hard drive was struggling with multiple read errors. My colleague also said it crashed a lot and some files had disappeared. A quick boot into Linux with my trusty USB stick (which is always in my pocket!) confirmed the SMART data on the drive showed it was unserviceable. So I gave him the bad news and suggested it needed a replacement disk.

We discussed use cases to decide on a size, and he ended up ordering a small solid state disk for about £25 including delivery. I showed him which screws to undo to swap the drive out and gave him a USB installer for Ubuntu, explaining that I didn’t have a way to get him a copy of Windows and he’d need to talk to someone else about that.

The new drive duly arrived, and my colleague was able to fit the disk and install Ubuntu from scratch using the USB stick I’d lent him. My colleague would be the first to say he’s not very technical, so I think credit is due to the GNU/Linux community for making Linux so easy to use these days.

Even more exciting (to me!) is that my colleague has absolutely no plans to go back to Windows. He’s found software to do everything he wants, says the machine is faster than it ever was and is happy to have an up to date and modern laptop for an outlay of £25.

I really enjoy helping people to try Linux and realise that when they thought they needed a new computer, they often don’t. Machines are saved from landfill, and resources aren’t wasted on an unnecessary new machine. Everyone wins!

If you’d like to try running Linux on your computer, I’d recommend trying Ubuntu because it is well thought out and works on most things with ease. You can download it for free from this link.

The RC2014 Computer

While at Liverpool Makefest last June, I bought myself a kit to build an RC2014 Z80-based computer.

The kit was very well made, with high quality circuit boards which accepted solder very easily, along with sufficient documentation to make the whole building process smooth and enjoyable.

I found the process quite educational too, as the design of the kit splits out the various functions of a computer into separate boards which then plug into a backplane with a common bus linking the parts together. It was good to see how the CPU, ROM, RAM, Clock and I/O all work together to make a functional microcomputer.

I was able to talk to the RC2014 from another computer over a serial connection, but I found I got the real ‘retro’ feel when I added the RC2014 ‘video card’ – which is a serial terminal based on a Raspberry Pi Zero. This meant I could plug my creation into a monitor and keyboard without the need for a separate computer, making the whole thing into a self-contained 8-bit microcomputer.

I also added an I/O board of LEDs and switches so I could interact with the computer without the need for a monitor or keyboard.

My RC2014 incrementing binary numbers…

You can purchase a kit yourself or find out more about this little marvel at this website.