LCD Frequency Counter PCB project
I picked-up an old Heathkit Sine/Square wave audio signal generator at a car-boot sale.
It is a very nice three valve design, and still works, apart from being a bit out of calibration.
I already had some LCD display modules and several old PIC16F84 microcontrollers, and decided to make a small frequency display to always be used with this signal generator.
A quick web search found the ideal solution – The Weeder Frequency Counter PIC 16F84 port by Peter Cousens, as published on the PIClist:
Frequency Counter,PIC 16F84,Weeder Technologies
Reading through the various links, I found an updated version of the software:
The Weeder Frequency Counter as expanded by Barry Smith for 16F628, 4 Bit LCD, USART output
I decided to make a single-sided pcb for that software version as it uses 4 bit LCD mode, keeping the circuit simpler and not bother with any pre-amp transistors.