Automated turntable photography

[Muris] has a friend who is selling items on the internet. This friend wanted a simple way to make rotating images of the products and asked him to help. The result of his labors is this base unit that drives the turn table and controls the camera.

The first iteration of the turntable was powered by the stepper motor … Read the rest

Polish your understanding of capacitors by building this meter

Building a capacitance meter is a great exercise. If you’re feeling quite safe in your digital-circuit-only life, this will push just far enough out of the comfort zone for you to see there’s nothing to fear in adding analog circuits to your designs. Here, [Raj] compares a voltage divider and RC timer to calculate the value of a capacitor. … Read the rest

DHT11 humidity and temperature sensor package

Temperature and humidity measurements are a nice addition to many hobby projects. But [Rajendra Bhatt] makes the point that many of these sensors have a price tag that is well above what most hobbiests are willing to spend. He decided to take an in-depth look at the DHT11 sensor; which you can get your hands on for under $3 … Read the rest

Three digit binary clock

Here’s a three digit binary clock that [Viktor] designed. It uses a multiplexed display to drive one digit at a time with a PIC 16F628A. The video after the break shows it ticking away, display hours, minutes, and seconds in blue LEDs. You may be wondering why those LEDs are not flush to the board? [Viktor] took the project one … Read the rest

Wristwatch board with throwback digits

This wristwatch circuit board has some pretty interesting digits. They’re older components that give a classic look to your wristwatch display. On board you’ll find a PIC 16F628A running with an external clock crystal. The display isn’t always illuminated (kind of like Woz’s watch) in order to save the batteries, but can be woken up for a short time … Read the rest

Modem used in an alarm system

This alarm system senses motion and then alerts you by phone. [Oscar] had an old external modem sitting around and, with some wise hardware choices, he came up with a simple circuit to use it. First up is the PIC 16F628A chosen because it doesn’t require an external crystal. This connects with the modem via a DS275 RS232 transceiver … Read the rest

Multi Multimeter clock

[Alan Parekh] built this clock to look like a Multimeter using analog multimeters for the three displays. A PIC does the timekeeping and feeds a specific amperage to the three displays which show hours, minutes, and seconds.

We’ve seen clocks that use analog meters before. [Alan] took the concept to the next level, replacing the graduated markings behind each needle … Read the rest