Help Trobleshooting my first solderless circuit on a breadboard

Question

I'm working on my first project from the book "Electronics All in One for dummies", chapter 6, book 1. I work through all the instruction but I cannot make the LED blinks. The circuit diagram is:

Here is an image of my breadboard circuit:

I have no clue on how to start troubleshooting it. What steps should I take to start troubleshooting a problem like this?

Appreciate all the help you can lend me. Thanks

Answer 1

I see a problem with the power supply. Pin 1 (green dot in my image) should be connected to ground, but you have the red wire connected to it which is the + pole of the battery. This means that C1 and R4 are also connected to + instead of -.

R1 and R3 should be connected to the positive pole but they are not, one is floating (not connected) and the other one connected to the ground.

Also pins 4 and 8 (red dots in my image) should be connected to the positive supply, in your image they are both floating (not connected).

To fix: (first disconnect the battery and then)

• Move the resistor wire shown with the blue arrow one position to the left (to the positive rail)
• Connect the black wire of the battery to the rail shown by the green arrow (where the capacitor,yellow jumper and a resistor are connected).
• Connect pins 4 and 8 to the rail shown by the red arrow.
• Connect the red wire to the rail shows by the red arrow (where the two resistors should be connected).

Answer 2

First off - good for you on getting this project going. This will be the first of many.

Looking at the LEDs, I can't see how they are plugged in, but the leads should not be on the same row going across (as the conductors on the breadboard in the picture you show go left to right). Otherwise the LEDs will be shorted out and will not illuminate. Rotate each 90 degrees if this is the case and modify your circuit accordingly.

Answer 3

It looks like both ends of your LEDs are connected to the same set of 5 tie points. That makes the right side of your schematic look like this:

^{simulate this circuit – Schematic created using CircuitLab}

There is never any voltage across the LEDs, so they don't light up.

Try moving the LEDs so that each end is plugged into a different column of the breadboard and report back on whether or not that works.