Other RP2040 boards • Re: RP2040 with ESP8285 on board

Basic FR4 board designs have included microstrip (RF transmission) lines for decades https://en.wikipedia.org/wiki/Microstrip and more specifically, Wi-Fi antennas for well over a decade. See for example https://www.researchgate.net/publicatio ... plications

I never said you can't do it with FR-4 as obviously the PIFA antenna is right there on the board. It is just this board that isn't doing anything like that. There is meant to be a cap there.

The ESP8285 section is a mildly altered copy paste of a ESP8285MOD design. "C20" is present in those modules but not C19 or L1. The most likely reason for the missing C20 is that it got accidentally left out. Margins on this type of module are low so it won't be worth reworking the boards.

The Pico+ESP8285 module includes a third, internal ground plane layer.

I don't have this module so can't check that.

If you soldered a capacitor to bridge the gap outlined by Willthrom, I doubt it would improve the Wi-Fi range and I also expect that if a capacitor did help, the value wouldn't be around 8.2pF.

I'm done here as you won't be convinced otherwise. For everybody else, buy a different module as this one is flawed.

Statistics: Posted by trejan — Mon Mar 11, 2024 12:38 am

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