Old projects that are still running

Discussion in 'General Electronics Chat' started by Brevor, Feb 2, 2015.

  1. Brevor

    Thread Starter Active Member

    Apr 9, 2011
    Do any of you have projects you designed and built that are still running after many years. If so I would like to hear about them. I have 2 digital thermometers I made. The first one I built in 1982 using one of those 7106? IC's. The second one is a re-design I built in 1997 using an Intel 8048 microcontroller. Both have been running 24/7 all these years.
    Last edited: Feb 2, 2015
  2. BReeves


    Nov 24, 2012
    Hasn't been running 24/7 but still works. In 1972 I designed and built a Color Organ, used triacs controlled by home made optocouplers made with incandescent bulbs and photo cells. Audio amp with 3 channel filters from caps and chokes drive the light bulbs. Hook it to the Christmas tree lights every year. Only failure has been the light bulbs.
  3. crutschow


    Mar 14, 2008
    I didn't design it but I built a Dynakit Stereo 120 (60w per channel), one of the first solid-state basic stereo audio amps, waaay back in the 60's and it's still going strong. Only had to replace one electrolytic coupling capacitor in all that time.
    I use it now to power the speakers on my computer for music and it still sounds really good.
  4. #12


    Nov 30, 2010
  5. AnalogKid

    Distinguished Member

    Aug 1, 2013
    The first balanced circuit I designed and built was a microphone preamp and cough gate for a TV station master control room announce booth. 1975, still in use today. The first digital project was in 1967, a game show controller my high school used to practice for the local TV quiz show. First person to press a button lighted a light and locked out all other buttons. All relays, but hey - gates is gates.

  6. Brevor

    Thread Starter Active Member

    Apr 9, 2011
    Thanks for your replies, I find them all interesting. I dug up another old project today, I built an outdoor lighting controller for a friend who owned a commercial building. It was installed 05/1994 runs 24/7 and is still working today.