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Open and Practice Measurement with PC. |
Updated:25.12.2009
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USB devices
Wireless devices
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USB Frequency counter 0 - 50 MHz
USB frequency counter is a small
module with good electrical properties. It is designed with
regard to achieve good electrical
parameters with the minimum requirements for hardware. Frequency
counter is connected with the
PC via USB cable and is also powered via this cable. Measured values
are displayed on the monitor of a PC or notebook.
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USB Frequency counter
Range : 0 - 50
MHz
Power suply : from PC via USB connector Software : USB Measure + API ( build your own application) Paralel
connecting : up to 127 devices connected is
possible |
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This
frequency counter is galvanically connected with a PC.
Version with the full galvanic isolation is also supported.
It is possible to simultaneously connect up to 127 USB freq.
counters. Software instalation is easy and completely
automated.
More about in the instalation page. Maximum
input signal is 10 Vss.
Frequency counter is calibrated using laboratory Frequency counter and deviation of the measured is almost zero. Frequency counter contains preamplifier with high gain , therefore the sensitivity is very good. It makes possible to measure the frequency of the small signals - a few mV.
Frequency counter is calibrated using laboratory Frequency counter and deviation of the measured is almost zero. Frequency counter contains preamplifier with high gain , therefore the sensitivity is very good. It makes possible to measure the frequency of the small signals - a few mV.
Software + API
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Software.
Software in the PC communicates with the USB device and display data on the monitor. Once installed it is already capable to work immediately.There is no need for settings. Software can communicate with multiple USB device at the same time. It also allows logs measured data into log file. COM component. For developers is supplied COM component, that enables to create own applications. COM component works with all popular languages like visual basic, C/C++, C#, javascript etc. More info are in help and in the software page. |
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USB Frequency counter
block diagram
1. Preamplifier.
At the input of frequency counter is limiter consists of 2 parallel diodes, followed by Fet transistor with high input impedance. The next amplifier stage is built with transistor BFR93A with high gain. Schmidt-Trigger provides signal amplification and form it to TTL level. Thus signal is suitable for processing in microcontroller. 2. Microcontroller as frequency counter.
Frequency measuring provides PIC16F886 ,that contains all the circuits needed to create frequency counter. Microcontroller 16F886 also sends data to the PC. 3. USB interface and PC communication.
Connection with PC is implemented by using USB converter with FT 232RL. FT 232RL is a reliable converter from USART to the USB protocol. It uses its own APIs and offers a lot of capacity for communication PC with a USB device.
At the input of frequency counter is limiter consists of 2 parallel diodes, followed by Fet transistor with high input impedance. The next amplifier stage is built with transistor BFR93A with high gain. Schmidt-Trigger provides signal amplification and form it to TTL level. Thus signal is suitable for processing in microcontroller. 2. Microcontroller as frequency counter.
Frequency measuring provides PIC16F886 ,that contains all the circuits needed to create frequency counter. Microcontroller 16F886 also sends data to the PC. 3. USB interface and PC communication.
Connection with PC is implemented by using USB converter with FT 232RL. FT 232RL is a reliable converter from USART to the USB protocol. It uses its own APIs and offers a lot of capacity for communication PC with a USB device.
More picture
Accuracy of freqeuncy counter.
Accuracy of freq. counter depends on the frequency to be measured.
Accuracy for hight frequency: f > 4 MHz is 0,001% ( maximal accuracy is 0,0001% )
Acuuracy for low frequency : f = 400 Hz is 1%
Resolution :
4 Hz - 4 MHz : 4 Hz
4 MHz - 8 MHz : 8 Hz
8 MHz to 16 MHz : 16 Hz
16 MHz to 32 MHz : 32 Hz
32 MHz to 50 MHz : 64 Hz
Accuracy of freq. counter depends on the frequency to be measured.
Accuracy for hight frequency: f > 4 MHz is 0,001% ( maximal accuracy is 0,0001% )
Acuuracy for low frequency : f = 400 Hz is 1%
Resolution :
4 Hz - 4 MHz : 4 Hz
4 MHz - 8 MHz : 8 Hz
8 MHz to 16 MHz : 16 Hz
16 MHz to 32 MHz : 32 Hz
32 MHz to 50 MHz : 64 Hz