Hey!
I have a wild idea that i’d like to implement, and it requires attenuating the wireless signal sent out by the Xiao Esp32S3 down to a point where the communicable range is reduced to ~10 to 30 centimeters.
How can I achieve this, does anyone know?
Many thanks!
Hi there,
Switch from internal Antenna to the external, and don’t mount the actual external one.
Try that?
HTH
GL 
PJ
so simple. i’ll try. many thanks!
That might burn the chip… fyi
You can set maximum transmitting power after the WiFi starts. You have to use
esp_err_t esp_wifi_set_max_tx_power(int8_t power)
ooh really?
could i ask why? or should i modify the little antenna that the unit came with somehow?
in general they warn for transmitters to not power up without an antenna because… basicly… without a proper tuned antenna, the energy is being reflected back to the source… as you can imagine… having energy reflected back to the source is bad…
Hi there,
Generally there’s not enough power output to DAMAGE anything , It just won’t work is all, Your thinking in terms of SWR and reflected power if there not a 1:1 ration or close. Like with high power HAM transmitters etc. Espressif documentation indicates and the Xiao has the proper matching Z so not an issue, it just will be weak or won’t go far range wise.
I wouldn’t modify the antenna that it comes with but you can place it inside the enclosure to limit the range to less than a meter.
HTH
GL PJ