PIC Freq Meter / Voltmeter

Measurement of the frequency up to 50MHz Measurement of power supply voltage in the range of 0.0 V - 25.5 V Measurement of the input voltage at two analog inputs, simultaneously displayed as bar graph (PWR/SWR or S) indicator. The input sensitivity could be chosen between 0.25V, 0.5V, 1.0V and 2.0V for maximum bar graph indication. This is a successor of the PIC16C71 4-digit LED f-counter & V-meter.

Some hard to find parts used in the previous version, which are out of production for some time, has been omitted. A rather early PIC16C71 has also been replaced by 28-pin device PIC16F876. The later is capable of driving 4 digit LED display in multiplexed mode while measuring frequency, power supply voltage as well as handle two analog inputs to display SWR/PWR signal strength in a bar graph manner. There is no need for external LED display driver chip as well as external data EEPROM since it is already implemented in PIC16F876. Reduction in the number of used chips also results in smaller dimensions of the counter compared to its predecessor.