Dana, my hero!
(probably the best answer I ever got from a forum)

regards Horst

Aw, you'll make me blush! I'm glad that I could help.

Cheers,
Dana

It's true the PCB has no silkscreen; fortunately, the "ESP32-LyraT Getting Started Guide" contains a link to a component layout:

https://dl.espressif.com/dl/schematics/ESP32-LyraT_v4.3_component_layout.pdf

Locate and remove C62, C64, C65 and C66. It is perhaps easiest to find these initially ...

I’m interested in this topic as well.

Dana,
Does the AI-Thinker board have these parts?

Bob

I can confirm that the AI-Thinker dev boards that I have, do not have these parts.

Cheers,
Dana

Hello there and thnks for the topic,
in order to remove the caps, would you hint me to locate them?
I can't find a pcb layout, so in the moment I am stuck.


It's true the PCB has no silkscreen; fortunately, the "ESP32-LyraT Getting Started Guide" contains a link to a component layout:

https ...

Thank you!

Dana

Thank you - I'm looking forward to more information.

Cheers,
Dana

I don't speak for either Espressif or AWS, but I'd say, compare schematics, look at the pin connections.

Odds are the Amazon FreeRTOS works on the Espressif boards based on the ESP32 modules. Note that Amazon FreeRTOS is based on FreeRTOS v10 and does not yet include the Espressif SMP extensions ...

Anything? I suppose no one uses that line-in circuit, eh? It's quite broken with those caps.

Agree that these components look out-of-place - I've asked someone on the hw team to figure out if these components have a use.

Any update? I removed C62, C64, C65 and C66 and now I've got a very decent line-in sound-card

Cheers,
Dana K6JQ

To confirm, I removed C62, C64, C65 and C66 from the board, and now I see good separation between left and right aux in, and equal amplitude (within < 0.01dB) between the two channels. Before, right channel amplitude was substantially reduced by the additional loading by C66.

I do not understand ...