Propeller clocks are nothing new to anyone who has been into electronics for a while. They use an idea called POV, Persistence Of Vision, which means that if something appears in the same spot consistently, at least 50-60 times per second, our brains think that it’s permanently there when it really is not. TV’s and Monitors use this method of display, so it’s not as uncommon as you might think.
After having seen so many propeller clock POV videos on Youtube, but no real description of how they work or how to build your own, I set out to make one and document how it was built. The Pyro Propeller Clock POV design criteria was short and sweet: be as simple as possible in order to encourage others to make their own, DIY style.
Pyro Propeller Clock POV – [Link]
My project is about a wind vane that provides wind direction via a digital output utilizing an LED configuration.The objective is to create an LED configuration were only one LED would light up, showing exactly the direction of the wind vane.
Electronic Wind Vane – [Link]
If you use opamps like the TL082/84 you’ll be in need of a “split” power supply. That is a power supply that has a positive voltage, ground, and the equivalent negative voltage (eg +5v, 0v, -5v). Since most audio signals are AC you need the opamp to operate in this range to be able to process them.
Creating a negative voltage from a positive one - [Link]
Vinegar – Distilled White Vinegar – diluted with water to 5% acidity (Meijer)
Peroxide – 3% solution (Meijer)
Salt – to taste. (Just keep adding it until the “fizzing” continues all by itself).
Hydrogen peroxide is what we call an oxidizing agent (a mild one), meaning that it easily accepts electrons from other species to form H2O (hydrogen peroxide itself is electron deficient). What happens when it “dissolves” copper metal is that a neutral copper metal atom releases two electrons, to form a Cu2+ ion in solution. All metals tend to release electrons to form positively charged species….we refer to anything that DONATES electrons as a reducing agents. The strength of metals as reducing agents varies and copper is a fairly weak reducing agent.
Hydrogen Peroxide, Distilled White Vinegar and Salt as a PCB Etching Solution – [Link]
We recently ran across another 3D printable PCB accessory on Thingiverse. This time it is a stand-off that slips on the edge of a PCB and the edge of a piece of plywood. This is a quick way to mount your PCB on the side of a project or into a project enclosure.
3D printable PCB stand-offs – [Link]
Today i created pcb for Lithium Ion / Lithium Polymer USB Battery Charger with MAX1811, and designed with eagle pcb software.
The MAX1811 is a single-cell lithium-ion (Li+) battery charger that can be powered directly from a USB port or from an external supply up to 6.5V. It has a 0.5% overall battery regulation voltage accuracy to allow maximum utilization of the battery capacity.
The charger uses an internal FET to deliver up to 500mA charging current to the battery. The device can be configured for either a 4.1V or 4.2V battery. The MAX1811 is available in a small 1.4W thermally enhanced 8-pin SO package.
PCB for USB Charger with MAX1811 – [Link]
Detect Alpha, Beta and Gamma radiation integrating any Geiger Tube and read this levels using Arduino. As well as from the terminal, the radiation levels can be shown using different actuators.
In order to improve the design along with the software application participation in the Forum is appreciated.
Radiation Sensor Board for Arduino – [Link]
This project creates a RGB LED lit love heart which is controlled by a PIC12F683 microcontroller. I designed the project as a gift for my wife on our 15th wedding anniversary (since she puts up with my addiction to electronics I thought she deserved something in return!).
RGB LED Love Heart – [Link]