PIC-FC1 Frequency Counter

Introduction

This is a Frequency counter with PIC Microcontroller. It is available up to 38MHz at Normal HF mode. It is also available up to 2.4GHz with Fujitsu's MB-506 external prescaler.

Specifications

Display mode	Frequency, Wave length
Resolution	1Hz, 10Hz, 100Hz, 1kHz 1mm (Wave length. Mimimum measuring unit is 1KHz)
Unit	kHz (Resolution = 1Hz) or MHz (Others) X.XXXm (Wave length)
Supply current	7mA (Using Input A) 25mA (Using Input B)
Supply voltage	5.1 to 10V

Measurement mode (Maximum measurement frequency)/Gate time(*1) :Input A

	1Hz resolution	10Hz resolution	100Hz resolution	1kHz resolution
LF mode (2.3MHz)	1sec.	0.1sec.	0.01sec.	0.001sec.
MF mode (9.5MHz)	4sec.	0.4sec.	0.04sec.	0.004sec.
MH mode (19MHz)	8sec.(*2)	0.8sec.	0.08sec.	0.008sec.
HF mode (38MHz)	16sec.(*2)	1.6sec	0.16sec	0.016sec

Measurement mode (Maximum measurement frequency)/Gate time(*1) :Input B

	1Hz resolution	10Hz resolution	100Hz resolution	1kHz resolution
LF mode (150MHz)	64sec.(*2)	6.4sec.	0.64sec.	0.064sec.
MF mode (600MHz)	-	25.6sec.(*2)	2.56sec.	0.256sec.
MH mode (1200MHz)	-	51.2sec.(*2)	5.12sec.	0.512sec.
HF mode (2400MHz)	-	-	10.24sec.(*2)	1.024sec.

*1) Measuring time is added above plus 0.1sec.
*2) It is not displayed correctly if the value is greater than "16,777,215".

Figures etc.

Added self-extract file for DOS and updated the contents of LZH file.
(11 Jul)

Schematic Diagram Main Parts List (25 Jul) Software (PIC-FC1.LZH)�@Important!! Agreement for Licence is here. Software (PIC-FC1.EXE) Self-extract file for DOS.

The specification of Hardware or Software of this counter may be changed the future. The source code of this counter maybe depends on the assembler.

Note

If you need more sensitivity, use 74AC04 or 74HC04 instead of 74HCU04 as U1. It may be better than 74HCU04, but the frequency response of 74HC04 may be worse.