7400 competition: Entries and reader’s choice

Posted on Wednesday, October 26th, 2011 in 7400 contest by Ian

Here’s a (hopefully) complete list of entries in the Open 7400 Competition. Please share your favorites in the comments below, your favorites will receive a special reader’s choice prize. Voting ends in 24 hours.

A few commenters will receive free PCB codes as a thank you for voting.

Check out the list below.

This entry was posted on Wednesday, October 26th, 2011 at 6:56 am and is filed under 7400 contest. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a response. Pinging is currently not allowed.

56 Responses to “7400 competition: Entries and reader’s choice”

  1. kmmankad says:

    IMO,a few of the better entries in descending order of awesomeness are,

    Capacitive Sensing, the Hard Way
    Discrete logic POV clock
    8-Channel, 6 -MSPS USB logic analyzer

    Do I get a free PCB,or is it random?

  2. Victor says:

    Capacitive Sensing, The Hard Way – very impressive project with versatile design decisions.

  3. uglyduck says:

    I liked most the “Analog comparator” project as it was one of the most unusual ones. Many others are interesting but nowadays there are too many people who can synthesize logic from 7400 components. I think the competition must show some uncommon ideas rather than complex projects.

  4. Florin says:

    The Capacitive Sensing, the Hard Way, really is “the hard way” so I have to appreciate the amount of work that went into building that but I also like the 7400 Logic E-reader.

  5. Hélio says:

    Capacitance meter is a very nice application for 7400s

    • Alvaro says:

      Thanks Hélio :) It was actually a bit stressing to build the thing, I was surprised it worked so well in a breadboard [actually I was surprised, due to all the variables involved, that it worked]. Glad you enjoyed it!.

      Pity I had not much time to work on it. Last IC arrived 3 days before the contest deadline, and it was a pretty much irreplaceable component – I had to delay all testing, and just sit and wait.


  6. Stephen says:

    my vote goes to “Capacitive Sensing, the Hard Way”

  7. Zdravko says:

    When I was younger I had always wanted to build a TTL clock. So the “CMOS digital clock” is my emotional favourite.

    The other interesting project for me is “Capacitive Sensing, the Hard Way”

  8. Thatcher says:

    I’m going to go for the full wave rectifier, just because that was the least expected for me. It doesn’t actually use the intended function of the chip, which I thought was pretty clever.

  9. My favorite is this one: Capacitive Sensing, the Hard Way

    The high-frequency mixed signal is awesome, but generating RS232 output with nothing but 7400-shift registers just blows my mind.

    A close second is Lights out game which sports an impressive amount of computation in its 42(!!) logic chips.

  10. Nigel says:

    Also gotta go with “Capacitive Sensing, the Hard Way”

  11. tinito says:

    My vote to the pen holder! I guess if there is some kind of prize for such an original entry ;)

  12. Rohit de Sa says:

    The best IMHO is Capacitive sensing the hard way, followed by the E-reader, followed by the 8ch Logic analyzer.

  13. Schazamp says:

    My favorite is the Police Lights and Siren for Toy Car. I am impressed by how fully featured the device is using just two logic chips, and it’s a very creative and practical example of how 7400 devices can be used to solve common, mundane problems.

  14. Hzyr says:

    Capacitive Sensing, the Hard Way is by the best imo. A second would be the lights out or also the e-reader is pretty cool.

  15. kiran says:

    Capacitance meter works great.

  16. leprud says:

    I vote for lazarus! incredible work!

  17. Henrik Brix Andersen says:

    My vote goes to Bertho’s Capacitive Sensing, the Hard Way due to the high quality documentation and very well thought-out design.

  18. Zeta says:

    i like the “capasaitive sensing” and the “Masochist’s video card” proyects.

  19. John says:

    Capacitive Sensing, the Hard Way is very well documented and a cool project.

  20. Carlos says:

    I vote for “Capacitive Sensing, the Hard Way” and “Masochist’s video card”

  21. Superfro says:

    My money is on Masochist’s video card, but honestly I appreciate everyone’s entry!

  22. Veronika says:

    Capacitive sensing was awesome and I really liked the combination of 555 and 7400 found in the money counter.

  23. Paul says:

    I vote for “Ternary base-3 electronics…”, because I strongly feel that ternary logic is a future of electronics.

  24. gagandeep singh says:

    May I know why my entry [ENTRY] 40×16 Led Display is not in the list of 7400 compition. Is it invalid entry or you just skiped it.

    • Ian says:

      I’m sorry, this posts was based on the 7400 category of the blog and some posts were miscategorized. Every email and post was recorded to a separate judging spreadsheet, your was included in the judging. I updated the post with your entry too.

  25. Karel says:

    “Capacitive Sensing, the Hard Way” gets my vote.

  26. Michael says:

    “Discrete Logic Drum machine” is getting my vote.

  27. Casey says:

    Gotta say “Lights out game”.

  28. Steve says:

    I vote for “Police lights and siren for a toy car”

    It may not be the most technical submissions, but I loved the end result product.

  29. Eric says:

    I love the E-Reader Project. O-Scope XY projects always amaze me…. I should build one up one of these days.

  30. SaakNeMah says:

    Can’t get more retro than the ‘Etch-a-Sketch Toy’!

  31. Rich says:

    “Capacitive Sensing, the Hard Way” is brilliant. A close second is the lights out game due to the sheer complexity.

  32. Asbjørn Brask says:

    “Capacitive Sensing, the Hard Way” is pretty awesome!

  33. Flavor says:

    I have to say that I really like the Discrete Logic Drum Machine.

  34. Nathan says:

    I’d vote for my own project, but I’m pretty sure my mom will vote for mine. So, there are a *lot* of really great projects. In my opinion, one of the best is the “Lights Out” game–it is documented well, a finished project, … and its a game!

  35. “Discrete Logic Drum machine” gets my vote

  36. pietja says:

    My first vote goes to “Capacitive Sensing, the Hard Way”
    Also good ones are the “Logic PLL based switch-mode power supply” , “Masochist’s video card” and the smallest clone of a 7400 “Homemade 7400”

  37. Alvaro says:

    I am competing for this :P

    Anyway, there are two projects here (yes, only two) that made me shake my legs, due to complexity, ingenious, documentation, and being almost “pure” 74x/40x series.

    One is the “Capacitive Sensing, the Hard Way”.

    The other one is “Etch-a-Sketch”.

    The first one shares many details with my own design. Although it’s simpler (that’s a good thing), but also does not have to deal with the frequency sweep my design does (clock varies from something about 4MHz to a mere 1Hz).

    My congratulations to all contestants. Some very good designs were submitted, and I expect a good one will be chosen [of course I expect mine to win! :)].

    It was a pleasure to design and implement the Capacitance Meter for this contest. It was the first thing that came to my mind when the announcement came out, and, since no one helped me choose another one, I decided to do it and submit it. Most parts had to be bought abroad (IC prices in Portugal are absurd).

    What made me smile was to see that actually, despite all the analogdigital problems, the design actually worked. I was euphoric :)


  38. I submitted an entry, but I really like the Etch-a-sketch!

  39. jethomson says:

    I have a couple entries in the contest but I vote for the _Lights Out Game_ because I think it deserves it more. There are too many great entries to chose from!

  40. Kaity says:

    Christopher Woodall’s Drum Machine gets my vote, for sure!

  41. rsdio says:

    There are several very excellent 7400 circuit designs in the list, but my favorite by far is the
    “Drum machine.”

  42. rsdio says:

    Oops, I didn’t realize that there were two Drum machines on the list.
    I actually intended to vote for Matt’s
    “Discrete Logic Drum machine.”

    The reason I am so impressed by Matt’s work is that there are many VCO chips out there, but he managed to design 74HC-based oscillators. Kudos!

    (no offense to Christopher Woodall)

  43. Andy says:

    I personally like the Discrete “Logic Drum Machine”

  44. jethomson says:

    Dear private web diary,
    I hope the winners are announced before the 1st. That way, when I lose, I can egg the judges’ houses on Halloween without raising suspicion. The perfect crime!

  45. Chad says:

    My vote is for the Homemade 7400. Excellent way to get around not having the parts you need!

  46. CazH says:

    Lights out is just so fun to play around with, also the game has a really nice finish! :)

  47. Mic says:

    “Masochist’s video card” is very impressive.

  48. Ben says:

    I really liked the Lights Out game.

  49. YT2095 says:

    They`re all really good! but most of them are the sorts of thing that I expected to be presented, I Seriously never figured on someone Having to make their own 7400.
    So my vote goes to the Homemade 7400 cct, I just love that sort of philosophy.

Leave a Reply

Notify me of followup comments via e-mail. You can also subscribe without commenting.

Recent Comments

  • Max: Seems like an unexpectedly violent way to remove the chip indeed. A hot air station should of course do the job just fine, but in...
  • jose: Part removal described here is pure butchery, the cheapest hot air station will do a fast and clean job removing the QFP, heat air to...
  • Cody: Yes please
  • Marko: armature -> amateur
  • Crawford: Dibs,