Organize and Share your Electronics the way you want. Sign-Up for a free account now. It takes only 30 seconds!

Mechanical webpage hitcounter

Mechanical webpage hitcounter

This counter would have an additional advantage, though: every time a person requests a page from my site, the counter would give a satisfying Click!. The more clicks you hear, the more people reading your pages.
A pulse counter like this is quite simple to control: every time a pulse is sent to its input, the number displayed by the cylinders inside mechanically is increased by one. According to the label on the side, this one needed a 24V-pulse to do its work. That could pose a problem: 24V isn’t something a PC usually works with: almost all ports use 5V.

There’s one exception, though: the serial port can output voltages of -10/+10V at 20 mA. Normally, that’s not enough: 10V doesn’t make the counter ‘click’ and even if it did: it needs more than 20mA to do its job. Luckily, I had a few tricks up my sleeve to make it work: if you set one pin on the serial port to output -10V and another to +10V, you end up with a 20V voltage difference, which is enough to allow the counter to do its thing. If we then store that 20V in a capacitor and use another output pin to discharge the contents of the capacitor on the counter, we have sidestepped the 20mA-restriction too.

Visit Here for more.

 

More Articles to Read

Single-Sided USB Charger
Single-Sided USB Charger
A FPGA controlled RGB LED MATRIX for Incredible Effects – the Hardware
A FPGA controlled RGB LED MATRIX for Incredible Effects – the Hardware
Using Nanotimers to Reduce IoT System Power Consumption by an Order of Magnitude
Using Nanotimers to Reduce IoT System Power Consumption by an Order of Magnitude
Replace a microwave’s beeping with the Windows XP startup sound
Replace a microwave’s beeping with the Windows XP startup sound
A DIY Laser Scanning Microscope
A DIY Laser Scanning Microscope
Reverse-engineering the surprisingly advanced ALU of the 8008 microprocessor
Reverse-engineering the surprisingly advanced ALU of the 8008 microprocessor
ESP8266 LED lighting: QuinLED v2.6 PCB
ESP8266 LED lighting: QuinLED v2.6 PCB
Switching LVDS Graphics in a Laptop Computer
Switching LVDS Graphics in a Laptop Computer
Teleknitting: TV-based string art
Teleknitting: TV-based string art
DIY Bubble Machine
DIY Bubble Machine
Start your day with Nerf target practice!
Start your day with Nerf target practice!
Teardown of a Peaktech 6225A
Teardown of a Peaktech 6225A

Top




Shares