Haris Andrianakis writes:
After some modifications on my UV exposure box (scanner) for better UV expose, i desided that a better pcb must me designed for switch timer. The old one had over drilled holes and it was designed and built on my very fist steps. Also the high voltage side from the low voltage wasn’t seperated as it needed to be safe.
So i redesigned it in a more compact and easier to use pcb. The firmware has been also updated and now you can program the timmer by using the two buttons. The time is calculated by timer interrupt triggering using a 32.768KHz RTC Crystal with better accuracy. The display update also has been changed from static to dynamic.
PCB Exposure Switch Timer V2.0 - [Link]
Jürgen Beisert writes:
I like the handy DCF77 signal. In this project no clock should use it, instead the computers in my home network should be served by a precise time reference. Due to the fact most other interfaces are no longer available on modern computers, it uses the USB to forward the prepared DCF77 signal to the host.
DCF77 to USB converter - [Link]
Bill shows the world’s smallest atomic clock and then describes how the first one made in the 1950s worked. He describes in detail the use of cesium vapor to create a feedback or control loop to control a quartz oscillator. He highlights the importance of atomic team by describing briefly how a GPS receiver uses four satellites to find its position. You can learn more about atomic clocks and the GPS system in the EngineerGuy team’s new book Eight Amazing Engineering Stories http://www.engineerguy.com/elements
How an atomic clock works, and its use in the global positioning system (GPS) - [Link]
Well, our meetings take place on wednesdays at 10:30 (sharp). A radio controlled clock is used to determine whether you are late (and must bring a cake next time) or not. Unfortunately the identical radio controlled clock in my office always shows a different time
After baking a lot of cakes, I thought about synchronising these disreputable clocks …
Homebrew DCF-77 Signal Generator - [Link]
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]