Extra eyes for PDB schematic and layout?

The board layout, front and back: I will be publishing the EasyEDA project and Gerber files this week. -Frank

Hi,

The antenna for U1, should have no components or copper or ground plane flanking it. You've got traces and components on both sides of the board, where there should be clearance for the antenna. With the current layout, the WiFi is sub-optimal. Didn't any of the 4 PCB designers pick up on this? I'm not a PCB designer..

It's worse.. just took a look at the Gerber files in the repo. There are three layers in the 6-layer! board, which have power planes on them - all across the antenna area.

It's worse.. just took a look at the Gerber files in the repo. There are three layers in the 6-layer! board, which have power planes on them - all across the antenna area.

Yep, the board above is the Revision 1 (code named Sox), the Revision 2 is code named Hoober. We went to 4 layers. We moved the Wifi antenna to have fewer traces underneath. I'm not expecting to use Wifi much because of the huge power consumption. Hoober Gerbers are at https://github.com/frankcohen/ReflectionsOS/tree/main/Devices/Hoober. I would love you to dig and criticize, that will make it better. -Frank

I can't see that you've supplied all the files, I can only see two layers:

I used PCBway to make the Hoober (rev 2) boards and Surface Mount Solutions in Santa Clara, California, for assembly. Both are great companies. I downloaded the Gerbers again from PCBway to make sure. Please check the repository again today., I did an update.  Hoober is 45.88x73.77mm, 4 Layers,Thickness:1.6 mm, Finished Copper:1,Surface Finish:HASL with lead. Let me know if this still isn't complete. Thanks! -Frank

It's hard to examine the files without a zip file of Gerbers, otherwise people have to download 600Mbytes of the github repo just to examine a few kbytes of Gerbers. If it were a single file in the repo, it could be downloaded easily.

Anyway, everything above the blue line should be absent. The PCB designer doesn't understand that you can't have ground/power planes flanking the antenna. Even if WiFi isn't used much, it's not a frequency of use or data volume issue; the times you want to use it, the radiation pattern is affected because of the planes and components. 

Good points. I added a Zip of the Gerbers at https://github.com/frankcohen/ReflectionsOS/blob/main/Devices/Hoober/Hoober%20Board%20Gerbers%20Avinadad.zip.

We're working on Rev 3 of the board (codenamed ThingTwo) and will incorporate your change for the radiation patterns. In the past we had the board physically cut out below the ESP32-Mini antenna array, we will do that again.

I'm concerned about the GPS for the same reason. There's not much information about the AT6558 internal frequencies. And I am considering using a tiny SMT antenna, though I am expecting a lot of problems getting accurate position and time readings. What do you recommend?

-Frank

Here are photos of the Hoober board - front and back - without components. 

Wouldn't doing it without the cutout be better for mechanical strength - just leave it without any copper traces or planes? The antenna is one of the heavier components and this design seems to higher the chances on physical vibration?

It's 34 mm round and fits into a wrist watch case. The case provides the strength. Still you make a good point, we will make sure the traces and planes are not underneath the antenna.

Who knows what additional uses this board will have! I'm hoping many.