Posting Comment for "555 Adding Machine"

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12th May 2013 16:58

Alan Yates wrote...


The circuit diagram is right there on the page. I am sure you can piece together the details and build your own.



18th April 2013 01:34

vinay wrote...

awesome work alan,i want to do this project..can you please send me the required details to do this project( for your reply.

Thanking you.

8th June 2012 11:46

Alan Yates wrote...


There are 9 decades, 9*10 is 90 last time I checked. :)



1st June 2012 18:24

Dmitry wrote...

there are 100 Red LEDs, C-language-style error, lol.

anyway, nice project!

3rd July 2011 18:03

Alan Yates wrote...

Hello Rob, long time no see! Hope you are well.

Thanks mate, yeah the 555 adding machine was pretty epic, lots of hours of soldering. Fun though, and really cool when it finally worked.

Has me a bit daunted for the relay computer though. That is gonna be quite a project when I finally get around to it.



18th May 2011 12:38

Robert Dyball wrote...

Congratulations Alan! Wow what an epic project.

All the best mate,


7th May 2011 20:10

Jellochaos aka George wrote...

I just want to let you know that I bookmarked your excellent website.

Every week, I will come back here and look for the relay computer. (y)

26th April 2011 22:16

Alan Yates wrote...

Thanks Peter!

26th April 2011 22:14

Alan Yates wrote...


Thanks mate.

Dave said "lifetime supply", not sure how many that is, but probably more than I'll ever use!



21st April 2011 21:48

Peter Parker wrote...

Congrats Alan and well done on a well-deserved win for the Australian section! (5xZyROzUmA on youtube)

21st April 2011 19:22

Hamman wrote...

Congratulations on winning the Australian entry !

How many LCD's did you win ??? :)

Congratulations from Ireland.