Introduction:　

• 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  

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
cautions: 
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

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

 CTCSS/DCS Decoder for ANALOG mode

　CDCSS  for ANALOG mode (N code only)

Package Contents  

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

Q&A of SF-401 plus Frequency Counter

Problem: Frequency counter cannot check VHF frequency

Solutions:

1) Swtich the ATT button into left hand side

2)  Then change the antenna into VHF or Dual band, as customer are using UHF antenna, but checking VHF band

3)  If you really using the UHF antenna to check it, please try to slant your radio to the frequency counter,