Sonic2k's Page ---> Projects ---> In-Car Wi-Fi
Broadband Internet in an automobile

 Table of Contents:

  • Design (Huawei B315 + Power Switch)
  • Power-On Timer Design
  • Design considerations for automotive electronics
  • Schematic and PCB layout
  • Fabrication, assembly, 3D printed housing
  • Installation in the vehicle
  • Final Thoughts
Motivation - i.e. why do it?
My family and I have mobile phone contracts. It is the only way we can really afford to have a decent mobile phone. There is no compromise on our part- Apple make excellent mobile phones.

Now when it comes to getting a contract that offers an iPhone, you have to start at the bottom to convince the mobile network that you're not going to "ditch" them and run off with an expensive phone. The way to do this, is to get a small SIM-only contract for LTE.

So we ended up with two data only SIM contracts, and we have elected to keep our prepaid SIM cards (to retain our numbers and not have to go change our number everywhere especially with the banks).

So with these SIM-only contracts, they will throw in a small crappy LTE router such as the one pictured below. We have two of them, and using them in the car is just a crappy experience for many reasons...

The HUAWEI E5576 CAKE-O-SOAP

Now, most people will tell me "But why do you need something else, the little router will work just fine?". Well the damn cake-o-soap doesn't perform quite well.
There are problems, one of which is excessive battery drain. These cakes of soap get hot, and they do not last long on battery. Then you have to charge them, and they do not want to switch off when you turn the car off.
They are apparently powered by "HarmonyOS" which is just slow AF. It takes nearly 2 minutes for these things to boot up and connect to the network. It is also a pain to get them to turn off when you need them to turn off.

Finally, the web interface to manage the cake-o-soap is utter shyte, because of course, the Chinese manufacturer wants you to use an app rather than a regular HTTP browser. The embedded web page is so badly designed that you will need to zoom and scroll your arse off to see the stuff that's centred in a page 8000px wide.

Before recently, Huawei used to manufacture a decent LTE router, and I have used one long-term in the past when I lived in an area with no landlines or fibre internet- the venerable B315 was a pretty impressive router, even though by today's standards its old. And it's still Linux based. With that in mind, I decided to look for one and found one at a local gaming store.

"But Sonic2k why doesn't your car have wi-fi?"
Because, I drive an old car. I am not rich nor do I wish to be.
Cars are fucking liabilities, not assets. For most though, they're status symbols.

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