Information on Duinotech Mega 2560 R3 with WiFi

Other Hardware 3rd Party Boards
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I have been familiarizing myself with the Duinotech Mega 2560 R3 with WIFI main board (Jaycar part XC4421) and I have a question. It has both a built-in PCB antenna and a U.FL coax connector to connect an external WIFI antenna. I am from a radio / electronics background and the RF output trace from the ESP8266 WIFI Chip pin 2 appears to go to both the U.FL socket center pin via a 30pF cap and the PCB Antenna via a 6.8uH inductor.
The image below shows this: -

Board
Board1920×1467 370 KB

Can anyone confirm that I can plug in an external antenna without changing any smd components please? It looks like you can!

As an aside, there is very little information out there for this board... that I can find anyway...
There was a schematic with the brand name RobotDyn for the same board but I found quite a few differences in the dip switch wiring.
I documented this board's schematic as per the image below: -

Duinotech XC4421
Duinotech XC44211920×1191 204 KB

It may help someone I hope?
Thanks for any help. Regards RB

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The other possibility was to remove the 6.8uH inductor from the board... this just leaves the external antenna connected via the 30pF capacitor. Makes some sense too.

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