top of page



  • The frequency meter capable of measuring the parameters of the frequency of the continuous carrier signal walkie-talkies , with signal strength indicator.
    it is the tool of choice for maintenance personnel ,test frequency and signal strength of wireless enthusiasts.

  • This portable frequency counter is designed for counting continuous wave signal comes from Two-way Radio. 

  • There are easy ranges for you to choose. The ranges cover most of the frequency of the two way radios you want to measure. 

  • Its four-button control is easy to use and its small size allows you to carry it anywhere you like.

  •  Work by  TCXO(Temperature Compensate X'tal (crystal) Oscillator) ,In the range of -45 ℃ ~ 65 ℃ can reach ± 2 ~ ± 4ppm accuracy

  • This include very interesting frequency areas such as 2m HAM radio, all VHF and UHF

  • DMR Radio signal e frequency counter.

  • Easy Battery level 

  • digital mode for DMR radio only, not for other digital device


Feature & Specification:

  •    Frequency range: 27Mhz-3000Mhz
    ! Note: (27MHz to 100MHz It can not be guaranteed and the corresponding normal emission appliance)

  •   CTCSS/DCS Decoder  (must be 136-174/400-520MHz)

  •    Frequency counter for DMR radio

  •    Frequency digital 0.000  or 0.0000  ( +-0.001)

  •    Work by TCXO( Temperature Compensate X'tal (crystal) Oscillator) 2~2.5ppm

  •     Frequency Response time:  0.2-0.5sec.( CTCSS/CDCSS >0.5-1sec) 

  •     TFT Color Display 240 x 320 ,LCD Dim level setting

  •     Build-in  Li-ion battery

  •     Net Weight: 113g 

  •     4 buttons control

  •     Auto power off  1-9minutes   

  •     Charging battery LED indicator  

PDF logo_png.png





Power On/Off                                    
Power On –Press and Hold down the [black key] by 2 second 
Power Off –Press and Hold down the [black key] by 4 second of number count down to 0
Charging the battery 
Plug the Power cord into adaptor , Micro USB connected SF-401, The Led indicating:
*The RED Led is light - Charging        
* The Green Led is light - Full 
How to check Frequency measuring.    See PIC.3


The transmitter near the frequency counter antenna , see the signal reception conditions is zone green, you can test. Please see Pic.3
e.g. display 1800.000Mhz  , The transmitter distance is too close to the frequency counter will affect the test results, , the signal bar is red .(see Pic.1)
e.g. display 0.000, , The transmitter distance is too far to the frequency counter and signal is weak ,will affect the test results,  the signal bar is low .(see Pic.1)
! Note: (27MHz to 100MHz It can not be guaranteed and the corresponding normal emission appliance) .


How to check Frequency of Digital DMR Radio 
Press[ F3 Digital] from Measuring screen mode   See PIC.1
Note: Use Digital mode have 3 Decimal only

MENU funtion setting and save.    See PIC.4
Press [F1] > into menu Page
Press [F3 down] or [F4 Up] into System and Press [F2 Rtn] into system Page PIC.4
Press[F3 down] or [F4 Up] select funtion ,Press [F2 Edit] > [F3 - ][F4 +] change mode
Press[Menu]  >  [F1 ]to Exit  or  [F4 ] to Save and Exit


Menu Setting
Rf defect level: The smaller the rf detect level, the more sensitive

How to check CTCSS/DCS code 
1.Radio must be 136-174/400-520MHz
2.Radio must be ANALOG 


Package Contents 


1x SF401 PLUS  Frequency Counter 
1x UHF Antenna 
1x English User Manual
1x USB charger cable
1x USB AC adapter 100-240V 

bottom of page