100MHz frequency counter using PIC16F628A

The schematic is fairly simple and straightforward and uses a PIC16F628A microcontroller for measuring frequency and a high speed comparator for signal amplification and conditioning. Timer0 is used to count the input signal at pinRA4. In order to achieve the maximum possible resolution, the input signal is probed for 0.125 seconds and the prescaler value is computed accordingly. The input of the schematic is feed through a high speed comparator. The two inputs of the comparator are set at about 1/2 of power supply voltage with 15-25mV difference between them so any AC signal with higher voltage will start switching the comparator. The input is protected with 1k resistor and two diodes limiting the voltage to ±0.7 V. The input impedance for low frequenciesis equal to R1 – 47k. For VHF range maybe it is good idea to replace it with 50Ohm value. The schematic have fairly low power consumption – with no input signal the supply current is 7-8mA and goes up to 20mA with 200+MHz input signal. Continue reading

Quick frequency counter with Arduino

Frequency is very important parameter of any signal. No matter if you are generating or synthesizing signals, you most likely need to measure its frequency. When signal frequency is bellow 40kHz and amplitude is near 5V then you can build frequency counter on Arduino with standard LCD screen. If measure signal is 5V (or 3.3V) level then you can feed it directly in to Arduino input. In other cases you need to use limiting circuit like amplifier or voltage divider. But this small project assumes that voltage is fed directly to microcontroller input. In this example signal comes to digital pin 12 where function pulseIn() counts number of pulses during specified time. Program itself is only few lines of code, and hardware is straight forward so putting it to work condition is only a matter of minutes. Continue reading

MSP430 frequency counter uses 8 seven segment displays

MSP430 frequency counter

This frequency counter is practically classic example of MCU based device. It captures frequency pulses directly to MCY pin without any special prescalling circuitry or even protection. So it is capable to accept 3.3V CMOS level signals. But it is designed as module which can be integrated in to end device if needed. The counting workload is done by MSP430G2202 microcontroller which is capable to count up to 10MHz signals. The display is connected to microcontroller using transistor based column selector decoded by 74HC238 and rows driven by MCU pins. One interesting feature included in this project is that counter can be calibrated to achieve +-10Hz error at 10MHz.   Continue reading

The Marvelous IK3OIL 16F84 PIC Frequency Counter

Well, some of you here might have built a few PIC frequency counter before, and fully understand about its usability in the electronic field. However, for those who never get in touch with PIC frequency counter, it’s an electronic instrument that being used for measuring frequency. Technically, frequency is defined as the number of events of a particular sort occurring in a set period of time. In order to measure the frequency, you have to use a counter to accumulate the number of events occurring within a specific time. Let’s say, after a preset period (1 minute, for example), the value in the counter is to be reset to zero automatically! By the way, we’re going to build an IK3OIL 16F84 PIC Frequency Counter. Most people are worry, as they might need to waste a lot of money buying the electronic components. Well, you know what? This IK3OIL 16F84 PIC Frequency Counter is very cheap, as the cost of the counter is cost you about US$2, while the display is only less than US$5! Frankly, this IK3OIL 16F84 PIC Frequency… Continue reading

The Plug-in and Use PRO-I/O Breadboard Development System

Breadboard, it either can be solderless breadboard, protoboard or plugboard is a very reusable solderless device. It’s always being used to build a prototype of an electronic circuit. Many electronic systems normally have been prototyped by using breadboard, from small analog and digital circuits to complete central processing units. Speaking of breadboard, the project that you’re about to develop here is the PRO-I/O breadboard development system. For your information, the main purpose of this device is to emulate various input and output devices in nowadays designs. Those important components that include into the device are: Switches, Pushbuttons, A 2×16 character LCD display, LEDs Small serial terminal, A frequency generator, A frequency counter, and Two voltmeters. The PRO-I/O is built based on an Atmel ATmega16 microcontroller and the whole design can be easily fitted into a small case. It uses a 40-pin keyed cable to connect to the target breadboard. The cable is equipped with all the input and output signals for the target interface. By the way, you also need to include a USB interface into the project instead of… Continue reading