ESP8266 Community Forum

- Sun Feb 08, 2015 10:09 pm #9290 Background
the esp-07 has a ceramic and a connection for an external antenna.
There is a serial capacitor between the external connector and the ceramic pcb mounted antenna
Issue
I have searched this board using "antenna" and there is some discussion of the impedance matching but no definitive answer.
Query
If an external antenna is used is all that has to be done is to just plug it in, or does the capacitor need removing first?

- Mon Feb 09, 2015 1:27 pm #9340 I have tried with the external antenna for the esp-07 that has the external connector and the ceramic antenna. The capacitor was not removed yet.
In a very rough experiment the external antenna appears to interfere with the ceramic antenna resulting in poorer reception.
The capacitor is very small. Removing it will be easy but putting back will be a challenge so I'm not in a hurry
Has anyone any information on what has to happen with the esp-07 to get the external antenna to work alone since in combination with the ceramic it seems to perform poorly.

- Mon Feb 09, 2015 11:00 pm #9363 I'm willing to try some hardware changes to test. How are you measuring signal strength?

- Mon Feb 09, 2015 11:49 pm #9366 Okay, here's the results from a simple test. ESP-07 about 10m from the AP through some walls, using AP stats for the measurement. External antenna is a wire type pulled from a dead laptop, unknown gain.

Ceramic only: pretty steady at -80 to -79
Unmodified module with external attached: slightly better at -79 to -76
Removed cap, external attached: far better at -72 to -62 and directionality was evident.

In my case, removing the cap was the right move when using an external antenna.