RIP Radio Shack EC-4013 Calculator

I got this calculator in high school back in 19something… a long time ago. I used it in calculus, college physics, statistics, last semester’s chemistry class… it was the calculator I grew up on.

A few weeks ago, some of the buttons on the fold-out section stopped working. It’s very sad but calculator microsurgery isn’t a priority.


  1. Greg says:

    I have the same calculator!!! I bought it in 1985.
    I have the same problem with some buttons on the right side pad.
    The quality is excellant!

  2. Mike says:

    The problem is with the ribbon connecting left and right side, which is hiden under welded plastic cover. Some of the metal path are broken due to folding and unfolding the cover. I can’t understand the manufacturer’s policy (Sharp?) not to continue production of one of the best scientific calc tools.

  3. Kristi says:

    It must be a cosmic conspiracy. I just googled Radio Shack EC-4013 because the 3 key has started not registering. The right hand side is fine. I purchase this calculator in 1986, my senior year in high school. It made it all the way to 2012. It has seen me through college, grad school and post doc. Its an old friend that I’m going to miss. Especially the easy metric to US standard conversions.

    Mourning a calculator. My sister is right, I’m a nerd.

  4. wle says:

    where is the battery in these things?
    i am tired of it blinking out when a shadow goes by…


  5. lee says:

    wle, sorry, dunno. I never had trouble with the battery. On mine, if you covered the solar panel, the display would shut off in like 5 seconds so the battery was more of a small capacitor. It would have to be pretty much so dark that I couldn’t see the display for the solar panel to not power it.

  6. wle says:

    battery is behind the display
    very hard to get to
    may not be able to reassemble
    snaps broke
    plus weird size battery
    but i did find it :)


  7. wle says:

    without battery, it would revert to HEX and GRAD mode or something weird every time the light went away


  8. lee says:

    Cool! Glad you found it!

  9. David Rock says:

    I got this calc in 11th grade 1985 and still using. It’s of my favorite tools. On mine the plastic at fold started splitting a long time ago. A new piece of black duct tape once in a while keeps it together. Everything works and no battery problem. Will be sad when it goes. Maybe I’ll post back here someday with it’s unfortunate demise, whatever it is :-)

  10. Lauren Scott says:

    I spent years using this calculator doing electronic design and embedded systems programming (mostly assembly lanaguage) in the 1980s and 1990s. The HEX and logical functions rock! You just don’t find those function much any more. Sadly, like many of these, the conductive traces between the right and left side failed and I was forced to abandon it sometime in the late 1990s.

  11. Loren Moriearty says:

    Still use mine every day. It’s seldom been folded shut as it sits open on my desk. No problems whatsoever. Bought it new around 35 years ago.

Leave a Comment

Do not write "http://" in your comment, it will be blocked. It may take a few days for me to manually approve your first comment.

You can edit your comment after submitting it.