It was some time ago that I got into Android Auto. I didn’t initially give it much thought because at the time I had a separate GPS unit and a CD player in my car. Well, times have certainly moved on since and now a GPS unit becomes outdated within months and CD players in cars don’t exist anymore. at some point, I had figured out that I could use my plex server at home to stream my CDs to my phone, and by extension, my car.
So I got on the AA train and it’s been pretty good. Recent years have seen an increase in AA wireless capability. None of my cars have that, but I have used it in rental cars. It’s pretty nice. So I decided I would try and replicate that in my own cars.
There are commercial devices that will do this for you. a dongle that plugs into the USB port your phone normally would, then that dongle communicates with your phone wirelessly. Those devices cost everything for $7 to over $100, and I suppose you probably get what you pay for. But, I’m kinda cheap, so my experience starts at the $25 point.
It worked ok, but more importantly was the lessons it taught me. I tried to overcome the shortcomings of that device with a DIY open source device, then tried to overcome the shortcomings of that one with another DIY device. This is the summary of what I got out of that experience.
These devices work by initially creating a Bluetooth connection with your phone, then creating a secure, exclusive wifi network with your phone. If you are not aware, there are two bands of Wifi, 2.4ghz and 5ghz. For the best experience, you need a phone and a device that supports 5ghz. why? because 2.4ghz is way too crowded. Everything runs on 2.4 and some of it is very powerful. Businesses, schools, places with security cameras, it’s all a flood of 2.4ghz traffic. And what you will find is if your phone is connected to the AA dongle at 2.4ghz, your connection is going to suffer. Audio will stutter, the connection may even completely drop out.
The $25 device I bought would only connect at 2.4ghz. At the time, I thought it was just a weak signal or tiny antenna, so I changed to a Raspberry Pi Zero W running this open source software. That worked a little better, but it still only connected at 2.4ghz. This is a limitation of the Pi Zero. So I upgraded again to a Raspberry Pi 4 running the same software. Now my dongle connects at 5ghz instead of 2.4ghz.
Is it better? Yes. is it perfect? No. It doesn’t stutter in the places the older devices did. It stutters in new places – ones that are flooded with 5ghz traffic. When it starts stuttering, I look around to see what could be causing it and multiple times, I have seen those giant antenna towers nearby. Pretty likely that’s the source. But anyway, there are FAR fewer places that flood the 5ghz spectrum, so it’s quite tolerable.
One other note, The commercial device worked pretty well right off the bat. The open source one, though, took a lot of patience. Like not minutes or hours, it took days. I have no idea why, but I would just leave the device connected and the first day, it would not even connect. The phone would perpetually be saying "Connecting to Android Auto". The second day, it might connect for 5-10 seconds then drop off. By the end of the second day, it could manage a solid connection, only dropping once. Then it just worked from then on out.
0 Comments.