Learn Electronics 4 - Exercise 18 | Homebrew Electronics

I was hoping to have more to post today but I'm a little frustrated with this exercise. I was able to test the three numeral LED (see video below) but after wiring up the very first 4026 chip, I got no response on the LED. I double and triple checked all my wiring using Figure 4-35. I made sure the pins that went to negative voltage went to negative... and the pins that wired to positive voltage were wired to positive.

I checked my pushbutton with an LED - I had it wired correctly.

I checked the 9V voltage... all columns were registering the 9 volts and I properly wired up the columns as seen in Figure 4-34.

So, I grounded myself (again) by touching my metal table... pulled out another 4026... wired it up and pushed the button. Nothing.

Ditto with a 3rd 4026 chip. At this point, I went back to my wiring. The notch on the chip is pointed up (away from the LED) so that would mean pin 1 is upper-left. I again verified all my pins were wired up but nothing. Either this 4026 series of chips I bought isn't working with 9V (and I bumped it to 12V but still no response) or I'm doing something seriously wrong.

I spent over an hour wiring and rewiring just a single 4026 chip... I've got to take a break from this and come back after I've not thought about 4026 chips for a while.

Anyone else have luck wiring this up using Figure 4-35? I just find it hard to believe that these 4026s can be that sensitive... I may have to go buy more before I can finish this exercise... but I'm hoping someone has a suggestion because I'm flat out of ideas.

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