Feature: 1. Output with LED indication,when the LED is low, the LED is off, and when the frequency is low, the LED is blinking,more clear and convenient. 2. Output frequency range grade is optional,use the shorting cap to select) to make the output frequency more continuously adjustable. 3. Generate square wave signal, adjustable pulse. 4. Compact and practical design makes it works more stable. 5. Widely applicable to multiple occasions,suitable for many equipments. Specification: Item Type:Pulse Frequency Generator Size:2.9 x 3.6cm / 1.14 x 1.42in Fixing Hole Distance:22.5 x 30.5mm / 0.89 x 1.2in Main Chip:NE555 Input Voltage:5V~15VDC.When 5V is supplied, the output current can be around 15mA; when 12V is supplied, the output current can be around 35mA. Weight:Weight: 10 g / 0.35 oz(approx.) Input Current:>=100mA Output Amplitude:4.2V V-PP to 11.4V V-PP. (The output amplitude will be different depending on the input voltage) Output current: ≥15mA (5V power supply, V-PP is greater than 50%), ≥35mA (12V power supply, V-PP is greater than 50%) Output Frequency: Low Frequency: 1Hz ~ 50Hz Intermediate Frequency: 50Hz ~ 1kHz Medium And High Frequency: 1KHz ~ 10kHz High Frequency: 10 KHz ~ 200 KHz Period T = 0.7 (RA + 2RB) C RA and RB are adjustable from 0 to 10K; C=0.001UF in low frequency gear; C=0.1UF in the intermediate frequency file; Medium and high frequency file C=1UF; C=100UF in high frequency, so the frequency of the waveform can be calculated by yourself. Package List: 1 x Signal Generator