WiPy antenna select

  • I am testing WIFI signal strength with external antenna on WiPy 3 with latest FW (1.18.1.r1). I am using this antenna: https://pycom.io/product/external-wifi-antenna/

    I scan for networks with this code:

    from network import WLAN
    wlan = WLAN(mode=WLAN.STA)
    nets = wlan.scan()
    for net in nets:

    I usually see rssi-values in the range -65 - -70, the same when I use the internal antenna. When I put my thumb over the integrated antenna rssi goes to appr. -85.

    Is this expected? Should I test this in another way?

    When connected to an access point the access point give the same information, when the integrated antenna is covered (external antenna selected) signal strength decrease.


  • I can confirm same behaviour with LoPy4 running FW 1.18.1.r1. Difference in RSSI in my case is more than 20dB because the module (and its integrated antenna) is enclosed in aluminium housing.

  • Reported this issue on GitHub as well:

  • There must be a problem with the antenna selection method, is there a problem with my code?

    I added this and now the external antenna works:

    from machine import Pin
    p_out = Pin('P12', mode=Pin.OUT)


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