Skip to content

4" Avionics

February 16 Order

Two orders were made today/

This from Data AllianceTotal. Total $76.17 CAD. alt text

And this from Digikey. Total $20.83 CAD. alt text

Progress marches ahead. We'll be ordering the GPS module

Sensors, PowerSim and Backplate Arrive

It only took 7 days for the boards to arrive this time!

alt text

Lessons

Sensor Module

For a reason I still don't quite understand, the only cables that have been working for the data transmission are USB-C to USB-A. The USB-C to UCB-C cables don't. I though it had something to do with USB 2 vs 3 but I've tried a both 2 and 3 and they work.

Test points, silk screen labels and an LED or two on the next version. Not necessary, the board works fine right now but it's important for troubleshooting.

PowerSim

Only some power supplies work. Macbook port doesn't unless there's I use an adapter thing, and my 40W Anker wall adapter doesn't either, Alienware ports do work. The reason for this is due to protection circuits present on some power supplies.

The idea is they don't want a live wire lying around because it acts like an inductor and could potentially have high transient current. So if you have a very very small load, it will just shut off the power to the port to prevent that.

Backplate

I used 0805 resistors. I could have made them even bigger. Soldering all the PCIe pins is more annoying than it looks. I wish JLC assembled that.

Next Steps

I'll be testing out CAN bus soon. I have 4 sensor boards to test with. (I broke one during testing) If all goes well I'll start work on the power module.

The CAD and 3D printing for the enclosure needs to be finalized as well.

December 28

Here are two images of the final prices for PCBs

The more expensive one uses standard assembly, the less expensive one uses economic. I thought standard assembly would cost a lot more.

Image 2 At first I designed the PCB with a sensors that were only available with standard assembly. It cost $205 I was like that's a little much.

Image 1 Then I redesigned it with all economic components. It turned out the feeders loading fee is the exact same for both because the standard fee is half of the economic fee and I had double the components.

So in the end it costs about $50 more to use much better sensors. That's only $10 a board. I think it's well worth it.

Rebranding

The site has officially been changed to Sonic Avionics. I choose this name because sonicavionics.com was available and it kinda rhymes. I changed dingboard's name to 4" Avionics. This is kind of sad, but we're gonna have to present to some committees and it wouldn't look good to have it called that. We lack credibility so a silly name would be seen as a negative thing. I promise to make the 6 inch avionics called dongboard.

One Month of PCBs

The power module 0.0.2 works perfectly.

Here's some photos of me testing it. I got heat shrink that's too big.

alt text

alt text

I even got the fuel gauge chip working.

alt text

A month into this project, and I got a working PCB! I'm happy about that. Not often it works on the first try either. It took 15 days for the PCBs to arrive and it cost $116.28 CAD for assembly for 5 boards including shipping and tax and everything.