7400 competition entry: Relative clock/timer/alarm

  Relative clock/timer/alarm designed by Victor, and entered in the open 7400 Logic Competition. Towards the end of the ’80s, when I started out in electronics, one day I decided to make a special alarm clock: one, that, when the time comes, switches on some device in my room – be it a radio, TV […]

7400 competition entry: Flickery LED bar candle

Looking for Halloween do-it-yourself project that will make your friends have a frightfully fun time? Check out T0m’s flickery LED candle: Here’s a 1 chip wonder. i wouldn’t call it the height of originality — just a bit of fun for Halloween! :) Build something that uses or abuses a logic chip and get amazing […]

7400 competition entry: Random number generator

Mike posted his hardware RNG based on discrete logic chips for the Open 7400 Logic Competition. Generating truly random numbers using a purely digital circuit is not possible – after all, digital logic is supposed to give the same results given the same input! This circuit cheats a little – a 4049 is used in […]

7400 Competition Reminder: Entry deadline is October 31st

Just a reminder to all potential entries that the deadline is October 31st. You now have less then 2 weeks to submit your entry. Good luck! Build something that uses or abuses a logic chip and get amazing boards, tools, and other swag. The Open 7400 Logic Competition promotes awareness of the basic building blocks […]

7400 competition entry: Passive RFID Tag from 7400 discrete logic

Check out Bertho’s RF74xxID, a multifunction passive 7400 RFID tag for the Open 7400 Logic Competition. RF74xxID: A passive RFID tag built entirely with 74xx logic chips. The tag supports the setting of any ID by means of DIP switches, can send data using two encoding schemes and has configurable baud rate. The tag is […]

7400 Competition Reminder: Entry deadline is October 31st

Just a reminder to all potential entries that the deadline is October 31st. You now have only 2 weeks to submit your entry. Good luck! Build something that uses or abuses a logic chip and get amazing boards, tools, and other swag. The Open 7400 Logic Competition promotes awareness of the basic building blocks of […]

Open 7400 prize: $25 gift cirtificate with free world wide shipping from Numato

Numato Lab donated a $25 gift certificate with free world wide shipping to the Open 7400 Competition. Numato is an online hobbyist electronics shop based out of Banglore, India. Get your entry in and this and other cool prizes can be yours. Thank you to Numato for sponsoring the 2012 Open 7400 Logic Competition!

7400 competition entry: Hacky random number generator / cat toy

Want to make your own toy for your cat? Tom’s random number generator shows you how: I decided to make a true random number generator. In particular, I wanted a latching RNG — not merely a continuous stream of numbers, but a continuous stream which I could sample at intervals. The circuit would be made up […]

7400 Competition Reminder: Entry deadline is October 31st

Just a reminder to all potential entries that the deadline is October 31st. You now have only 2 weeks to submit your entry. Good luck! Build something that uses or abuses a logic chip and get amazing boards, tools, and other swag. The Open 7400 Logic Competition promotes awareness of the basic building blocks of […]

Open 7400 prize: RaspberryPI from HubCityLabs

HubCityLabs hackerspace from Moncton,Canada is the latest sponsor of the Open 7400 Competition. Up for grabs is a Raspberry PI for a Canadian entry. This and other prizes could be yours, but only if you get your entry in soon! Thank you to HubCityLabs for sponsoring the 2012 Open 7400 Logic Competition!

7400 competition entry: Data encryption and decryption system using 74xx logic gates

Nakul built a 7400 based data encryption and decryption device. It works on the cellular automaton algorithm: Encryption and decryption plays a vital role in today’s digital world. So we thought of implementing an encrypting and decrypting device using only 74xx logic chips. The encryption algorithm is based on cellular automaton. Rule 30 of the cellular […]

7400 Competition Reminder: Entry deadline is October 31st

Just a reminder to all potential entries that the deadline is October 31st. You now have only 2 weeks to submit your entry. Good luck! Build something that uses or abuses a logic chip and get amazing boards, tools, and other swag. The Open 7400 Logic Competition promotes awareness of the basic building blocks of […]

7400 competition entry: 4-bit SAR analog to digital converter

Marco entered a 4-bit SAR ADC made from discrete logic chips 74xx & 40xx series for the Open 7400 Logic Competition. The SAR (Successive approximations) works by comparing the analog value to be converted with a generated value with a method similar to the mathematical bisection method. More precisely, it starts comparing, by a simple difference, the input […]

7400 competition entry: Telemetry Beacon for HAM Sats

Mani entered a Telemetry Beacon for HAM satellites using Logic gates for the Open 7400 Logic Competition. The beacon controller is intended for telemetering of data available on board of the Ham radioSatellite (originally designed for the Indian Satellite VUSAT in Morse code so that the hamradio operators can decode the info without any costly and […]

7400 competition entry: 4000 series CMOS 24 hour clock

Easton made this 4000-series CMOS 24-hour clock as a final high school electronics class project. Rather than using a microcontroller he chose to use CMOS ICs including a 4060 and 4013 to generate the 1Hz signal. This is the latest entry in the Open 7400 Logic Competition. For the last couple months a friend and […]

7400 competition entry: DIY 6502 computer

6502s are 8bit microprocessors from the 70s developed by MOS Technology. Sweet thing is they come in DIP-40 trough hole packages, although we doubt an emulator based on 7400 logic chips will fit the same package. Check out André’s DIY 6502 computer for the Open 7400 Logic Competition. I have built a DIY 6502 computer, […]

7400 competition entry: 4049 inductance meter

Mike’s 4049 inductance meter converts inductance into voltage, which can be read via any multimeter. Check out the latest Open 7400 Logic Competition entry: All the decent multimeters nowadays seem to have a built in capacitance meter, but only a few of the really expensive ones have a built in inductance meter. Dedicated inductance (LCR) meters, of course, […]

7400 competition entry: TV Auto-off from the ’80s

Are you tired of watching TV and want to turn it off quickly from your armchair? Viktor’s TV Auto-off shows you how: The idea was to have a tiny light come up right next to the TV after a preset period of time. If my grandpa is watching TV he would notice it and press […]

Open 7400 prize: Au$100 gift voucher from Little Bird Electronics

Little Bird Electronics donated a Au$100 gift voucher for the best Australian entry to the Open 7400 Competition.  It is limited to a participant in Australia only. Thank you to Little Bird Electronics for sponsoring the 2012 Open 7400 Logic Competition!