Here's how to check your carrier's frequency on your iPhone

  • Step 1

    Key in *3001#12345#* and press call

  • Step 2

    Tap: menu

  • Step 3

    Tap:Serving Cell Info

  • Step 4

    Scroll down to freq_band_ind

The number in that column is your signal frequency.
For example, freq_band_ind 41, then you should choose the mobile phone signal amplifier of band 41.

Reminder

*Make sure to check the frequency where you need to boost signal.
*Before checking the frequency, kindly turn off the WiFi.
*While checking, stand in a place with a good outdoor signal.
*Try standing in different positions and checking multiple times to avoid any inaccurate results due to unstable signals.