For example:Display 100 means PWM output frequency is 100Hz;Display 1.01 means PWM output frequency is 1.01KHz;Display 54.1 means PWM output frequency is 54.1KHz;Display 1.2.4 means PWM output frequency is 124KHz; Set PWM frequency:F101:Set frequency is 101Hz.101 can by replace by 001~999;F1.05:Set frequency is 1.05KHz.1.05 can by replace by 1.00~9.99;F10.5:Set frequency is 10.5KHz.10.5 can by replace by 10.0~99.9;F1.0.5:Set frequency is 105KHz.1.0.5 can by replace by 1.0.0~1.5.0; Frequency set range:Enter the settings interface when short press any button FREQ+ or FREQ- in the normal running status to select frequency range.Automatically switch frequency range.Pay attention to the position where the decimal point moves when the button is pressed.Display XXX. No decimal point,The minimum frequency is 1Hz.The frequency range is 1Hz ~ 999Hz.Display X.XX.The decimal point is the penultimate, The minimum frequency is 0.01KHz.The frequency range is 1.00KHz ~ 9.99KHz.Display XX.X.The decimal point is the third last,The minimum frequency is 0.1KHz.The frequency range is 10.0KHz ~ 99.9KHz.Display X.X.X.The decimal point is fully lit,The minimum frequency is 1KHz.The frequency range is 1KHz ~ 150KHz. Duty set range:Enter the settings interface when short press any button DUTY+ or DUTY- in the normal running status to select duty .Automaticallyswitch frequency range.Duty range is 0.00%-100%. Use steps:Connect to power supply;Short or long press button FREQ+ or FREQ- to set frequency;Short or long press button DUTY+ or DUTY- to set duty ;Connect to load.UART communication and parameter settingsThe system supports UART data upload and parameter setting functions (TTL level); UART: 9600, 8, 1 LCD high definition display;Support UART;Support frequency adjustment;Support duty le adjustment;High precision detection; Support power-down memory function; 1-Channel PWM output. Work voltage:DC 3.3V-30V;Frequency range:1Hz~150KHz;Frequency accuracy:2%;Duty range:0.00%-100%;Output Current:About 5-30mA; Output amplitude:Same to input voltage; Operating temperature:-20 Celsius~70 Celsius Set PWM duty :DXXX:Set duty is XXX. XXX can be 000-100.E.g:D051 means PWN duty is be set as 51%. Read set parameter:Send read and then parameter.Return value:Return DOWN:Set success.Return FALL:Set fail. Application: Square wave signal generator, generating square wave signal for experimental development;Used to generate a square wave signal that controls the motor driver;Generate adjustable pulses for use by the MCU;Dimmer;Speed governor; colour:gray Material:plastic size:4.3*2.7*7.9CM Package Contents: 1*Signal Generator Note: It's 1-channel PWM output signals are the same.They can not adjust independently. Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.