The virtual frequency meter is the program for PC and simple measuring instrument, which is connected to COM to port of the computer. The virtual device allows to measure frequency, period, time frames and score impulses.
Frequency, Period, Time Frames, Score Impulses Metering
2.1.Analog Signal Metering Frequency range 0.1Hz – 250kHz
Amplitude range 0.1V – 30V
2.2.Digital Signal Metering Frequency range 0.1Hz – 5MHz
Low level 0.1V – 2.0V
High level 2.5V – 30V
2.3.Measuring Time 1mS,10mS,100mS,1S,10S
3.1.Time range 10mkS – 10S
3.3.Measuring Time 1,10,100,1000 Periods
3.4.Input Signal Analog or Digital
Time Frames Metering
4.1.Time range 10mkS – 10S
4.3.Input Signal Analog or Digital
The device is mounted in casing of 25pin connector.The device has supply from signal lines of COM port only. In programing mode it needs an external +5V. Components: resistors and capacitors – 1206type, transistors – BCW32L(npn) BC859C(pnp),diodes – BAS32L, zener diodes – BZX84-C4V7, quartz 10MHz.
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