數碼對講機(DMR) 類比 訊號測頻儀。

支援頻段：136MHz-520MHz
可測CTCSS / DCS 內碼數值 
自動背光。  
內建鋰電池，使用MICRO USB充電。商品包含：

SF-401PLUS計頻器x1
12.5cm天線x1
110V~240V變壓器x1
MINI USB充電線x1
說明書x1
商品特色：
大型彩色LCD液晶顯示
TCXO溫度補償晶體振盪器
(-45度～65度達到±2~±4PPM)
類比可測(頻道+內碼)數位只能測頻道
量測頻率：136~520MHZ
天線長度12cm
重量：103克(不含天線)
尺寸：高9cm/寬7cm/厚2.7cm


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 
  

Feature & Specification:

•    Frequency range: 27Mhz-3000Mhz
•   CTCSS/DCS Decoder
•    LCD Dim level setting
•    Frequency digital 0.000  or 0.0000  ( +-0.001)
•    Work by TCXO(Temperature Compensate X'tal (crystal) Oscillator) 2～2.5ppm
•     Frequency Rresponse time: 0.2-0.5sec.( CTCSS/CDCSS >0.5-1sec) 
•     Color Display 240x320
•     Build-in  Li-ion battery
•     Net Weight: 113g 
•     4 buttons control
•     Auto power off  1-9minutes   
•     Charging battery LED indicator  

Specifications for SF-401 and SF-401 PLUS
Brand Name:	SURECOM HK	SF-401	SF-401-PLUS
DIGITAL RADIO signal	DMR	No	YES
Signal  attenuation s.w.	-10db	No	YES
Battery Buily-in	level	Voltage	Easy icon
Flash Light	LED	YES	NO
TFT LCD:	320 x 240 pixels	YES	YES
Frequency Range:	27MHz -3GHz	YES	YES
Li-ion Battery build-in :	3.7V 600mah	YES	YES
current consumption:	10ma	YES	YES
TCXO crystal Oscillator	+- 2.5ppm	YES	YES
Changer in:	Micro usb +5V	YES	YES
impedance input:	50 Ohm (BNC)	YES	YES
Weight:	113g	YES	YES
Dimensions size :	70 x 25 x 90mm	YES	YES

SF-401/PLUS

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 anetnna , 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)