Simpleclock is an easy to assemble attractive 4-digit 7-segment LED display clock with temperature and alarm function. It is available in three display colors: Red, Blue and White.
It comes as a kit of through-the-hole parts and can be soldered by any person with basic soldering experience. An attractive acrylic stand is included.
Simpleclock: An LCD clock kit suitable for beginners with open source Arduino firmware - [Link]
The DS3231M breakout board is a compact breakout board for the new DS3231M high precision real time clock chip. With it, you can add timekeeping and alarm functionality to any Arduino (or other microcontroller that supports the I2C/TWI protocol).
The board comes with an onboard CR1220 backup battery (keeps time when main power is disconnected). All pins on the chip are broken out, allowing you to use extra features such as 1Hz and 32kHz square wave output, interrupt on alarm and reset.
DS3231M Real Time Clock Breakout - [Link]
Haris Andrianakis writes:
This is a project i designed a year ago but never built, because of not enough spare time. This month i found some free time so i started building it and i send the pcb layout for manufacturing.
All started when i received some IV-11 vfd tubes from an ebay seller i ordered from and i started testing and prototyping by first trying to simple light up the VFD tube.
A VFD tube works like a 7-segment led display with some small differences.
A) The Filaments. The Filaments exists to power the tube. We have to supply these two pins with 1.2Volt and nothing more (polarity doesn’t matter).
B) The Grid. The Grid is like the common anode of a 7-Segment LED display. So the Grid has to be pushed high at 60Volt (in these tubes) in order the segments to be able to light up.
C) The Segments. The Segments light’s up simple by pushing them high at 60Volt.
IV-11 VFD Tube Clock Final Design - [Link]
The Binary Burst clock shows the time with LEDs:
The clock uses 3 LEDs on each spire to count up to 5 in binary. The hours are displayed by the middle LED in RED (Its a Red/Blue bicolor, the others are just blue). Video, and links to the board and code repository are included in the post. Check out a demonstration video below. There’s also a time-lapse soldering video of build. [via]
Binary Burst clock ticks away the time with LEDs - [Link]
This device is a countdown timer specially designed for PCB exposure box.You can set how many minutes will be on UV light device , store this time in PIC’s EEPROM . Pressing start button lights are on until preset time ends. When lights are off an audible signal is heard. Microcontroller used is Microchip’s PIC 16F877. I used Mikroelektronika Mikropascal compiler to program the chip. Delay time 1-255 minutes.
Count down timer for UV PCB exposure boxes - [Link]
This is a good looking and practical device that can be useful in many areas where countdown timer is needed. This project is based on the PIC16F84A microcontroller. The time range can be adjusted between 1 and 999 seconds. This project has 3 buttons and one of them is named Set Button. In order to regulate the seconds up or down on the display you should press the Set button while pressing the button on the left or the right hand side. The author of this project is @Pedja089. More photos on Facebook Fan Page.
Timer from 1 to 999s with PIC16F84A - [Link]
Using a better antenna to improve DCF77 reception on long distances
We are in the prototyping phase of building a Nixie clock using 1N-14 Nixie tubes. The clock is designed around a PIC16F886 MCU, 74141N BCD decoder/driver and CNY74 optocouplers using common circuit topology. High DC voltage (+ 180VDC ) is generated using MAX1771 step-up switching regulator, which is quite efficient (if you use appropriate components).
Our clock will have some nice features:
- Compact design
- Manual time configuration
- DCF77 time synchronization
- Sync success indicator
- HV shutdown during sync (to reduce noise received by DCF module)
- Super-capacitor time backup
- Thermal protection
- ICSP connector etc.
When clock is complete we will release it as open source-hardware here at Electronics-Lab.com
We decided to use DCF77 signal as time reference for two main reasons, it’s quite easy to receive it and it’s very accurate for the reason that carrier signal is generated from atomic clocks.
But, what about receiving and decoding DCF77 signal? Read the rest of this entry »
This is a countdown counter based on ATtiny2313, primary developed for my PCB exposure box, but it can be used for other purposes too.
The counting range is between 1 and 90 minutes and it can be adjusted with up or down buttons (high and low in the pictures).
After the desired time is set, the countdown starts by pressing the start/stop button (on/off in the pictures). By pressing the same button we can interrupt the counting at any time we want.
After the count expires we hear a beeping sound and the load is disconnected. By pressing start/stop button we reset the counter and we are ready for another lap. All actions included the time remaining are shown in the LCD display.
Pcb countdown timer - [Link]
Matthias Franz writes:
The time manipulator is the little brother of the time signal transmitter located in Mainflingen close to Frankfurt in Germany. The very low frequency transmitter located there has an output power of 50 kW and is called, in accordance to its call sign, DCF77 (similar to HBG, MSF, RWM and WWV, WWVB, WWVH). The transmitter is operated by the Media Broadcast GmbH and transmits on 77.5 kHz the official time signal for Germany. The medium range is stated with 2’000 km.
My time manipulator however offers some more functionalities. It’s the true alternative if you have difficulties to find your flux capacitor or your local electricity supplier canceled your contract after you had difficulties to pay off for the 1.21 GW.
Homemade 77.5 kHz DCF77 time signal transmitter - [Link]
I was looking for, what I thought, was a simple clock/timer design. Something with a remote and a big display that could be read from across the gym and that I could program with up/down counting but also intervals specific to CrossFit like Fight Gone Bad or tabatas. I wanted to incorporate a bell to give it a gym feel and something that could be heard over loud music. This journey took me through many designs, chips, a custom board, wood working and a whole lot of learning!
Arduino CrossFit Timer - [Link]