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|Written by Hans Summers|
|Saturday, 28 March 2009 23:59|
Welcome to the most popular page on my website! I receive more emails on this project than any other, and several people have sent me photographs of the versions they have built. Scroll down the page to see pictures of binary clocks built by other builders.
Some time after my Sidereal Clock project I built this simple novelty clock, which displays 24-hour time in binary.
All the parts for this clock came from scrap. The red LED's making up the display came from an old video player. The high brightness green LED was also from an old video player (a different one). The TTL logic chips were from old computer boards, with the possible exception of the 4518 counter chip, which was probably a left over spare from my Sidereal Clock project. The transformer came from an old audio cassette player. I later needed the 74LS393's elsewhere in my Z80 computer, which is why the photograph above is minus these chips (and obviously doesn't show the clock in working order!). The clock was built on pieces of plain matrix board, which has holes on a 0.1-inch pitch with no copper tracks. Connections are made using point to point solid-code wiring, using wires from old telephone cabling. This is my preferred construction method. I didn't ever get around to boxing this clock.
LEFT: My original hand-drawn circuit diagram (binary clock schematic).
There's also this circuit diagram binaryclock.sch, sorry I can't remember who sent me this one.
NOTE:I believe my hand-drawn circuit diagram is an accurate representation of the circuit I built. I have not checked the two computer diagrams carefully against my hand-drawn one. I think that there is an extra incorrect pair of diodes between the hours and minutes set button on the centre diagram.
Alternative timebase circuit
Derek Tombrello had some difficulties with the timebase. It seems that a noisy local mains voltage caused his clock to run fast. He came up with an alternative way to extract a 1Hz pulse from his local (60Hz) mains frequency. CLICK HERE to view the circuit diagram. Scroll down the page to see photographs of Derek's clock.
Crystal timebase modification
Martin Keller (Germany) sent me a modification to run the binary clock from a quartz crystal reference rather than using the 50Hz mains frequency. CLICK HERE to view the circuit diagram.
NOTE: The 74LS08 and 74LS393 could be replaced by their more modern 74HC-series variants, i.e. 74HC08 and 74HC393. The latter are cheaper, more easily available (nowadays) and have lower power consumption. If you do this, then you can replace the 2K2 pulldown resistors wherever you see them, with something much higher e.g. 100K. There is also a 74HC4518 if you can find it, but if not then the plain old CMOS 4518 is still perfectly Ok.
The photos below have been sent to me via email from other binary clock builders. If you've built this project too, why not email me a photo for the gallery! Please click the photos to view full size versions.
Jeremy Balogh, EE Student at Nother Illinois University, USA
Bulent Uysaler also provided a nice PCB layout. I have .DXF and .PCB files available if you need them, Click here to download them: p3.dxf, p3.pcb (you need PCAD to view these files), and p3.pdf. Bulent even sent me a short video of the clock in operation!
Derek Tombrello. See also his alternative 1Hz circuit.
Jacob Toft Pedersen, Denmark
Oscar García, José Luis Solís, Armando Rodríguez, students of the Mechanical and Electrical Engineering college in Monterrey, Mexico. This is the final year project of their course.
Stuart Metcalf, UK. Visit Stuart's Blog for more information and photos.
Eben Rauhut, Cranford, New Jersey, USA
Ivo Naumovski from Macedonia says: "some time ago surfing I've come across your binary clock and immediately know I have to build this, because it's so cool. So I did build it using Bulent Uysaler PCB layout and it works excelent. thanks for the schematic!"
Göblyös János from Hungary, uses a microcontroller instead of discrete logic.
Felix Engel, Germany. Visit http://2501.fcenet.de/site/misc/binaryClock.htm for more information and photos.
Didier Salembier, Belgium built this true-binary clock which is described as an Open Source project. He writes:
"This binary clock gives you the exact hour in full-binary (no BCD!) and is driven by a 1MHz-oscillator. The hardware is very simple: only one MAX7000s (programmable logics) programmed with Quartus (free to use with weblicense). The source-code to upload into the EPM7064SLC44 (a /10-version is more then fast enough!) can be found on the website you see on top of this email and the hardware itself is just the basic hardware: connect the supply, the LEDs, the switches and the oscillator and enjoy your binary clock :-)
"On the same website you will also see the previous releases and the problems I encountered. You will also see I'm planning to make a brand new binary clock with an AVR instead of a MAX7000s, using DCF77 or the internet to adjust the clock.
"I've demolished an old alarm clock, I use the snooze-button to set the hour and I use the battery-place to upload new firmware into the clock. The D's and the C are not in use anymore (that was just a try-out)".
Virgil Ryan Bartolome (and friends) from The Philippines, built this very nice student project.
|Last Updated on Sunday, 02 January 2011 13:10|