Police lightbar

Thread Starter

archangeljess

Joined Dec 27, 2013
34
Good day to everyone!

I am very new to electronics the fact is I just want to a police-like flashing light on my son's toy car. I have searched for the schematics and found one to work on. This is the schematic of it:


I have bought all of the parts at a local electronics shop. My problem is when i try to build this on a breadboard, nothing happens. Well maybe I made a mistake in mounting the parts. I am a complete novice on electronics. I am a programmer by profession and I thought having electronics knowledge would be great.

If somebody could guide me on this or suggest a tutorial on how to read and build from a schematic, it would be a really great help.

Thank you and God bless.

Jess.
 

MrChips

Joined Oct 2, 2009
22,869
It might help for you to take a clear, well focused photograph of your breadboard and post it for us to look at.
 

Wendy

Joined Mar 24, 2008
22,236
I have designed several of these in my time, including high power versions. Mr. Chips idea is a very good one though.

There is an old open source saying, many eyes do bugs eliminate.
 

Thread Starter

archangeljess

Joined Dec 27, 2013
34
Here is what I did on the breadboard:






I hope I haven't messed everything up. Thanks for the help guys.

P.S.
I appreciate you guys helping me and I didn't realize it was early in the morning your time. Its around 1PM Philippine time.
 

MrChips

Joined Oct 2, 2009
22,869
Check the vertical bus rails.
These could be discontinuous at the mid points at holes 30.
Install jumpers on all four rails.
 

Thread Starter

archangeljess

Joined Dec 27, 2013
34
Check the vertical bus rails.
These could be discontinuous at the mid points at holes 30.
Install jumpers on all four rails.
I am very grateful for your reply but I am a complete novice. I really don't know where those holes are. There's nothing connected to hole 30. In the picture the breadboard is inverted.

Could you point this out for me? I'm sorry for being so stupid.

Thanks a lot.

Jess
 

MrChips

Joined Oct 2, 2009
22,869
I know my instructions are not clear. I am not able to post a picture for you.
Look at what Bill Marsden has circled in red.
You need four jumpers like these.
 

Thread Starter

archangeljess

Joined Dec 27, 2013
34
Yes, I didn't know the breadboard I have isn't entirely connected. I'm so sorry. Thank you both for the help. I'll try this one in a moment.
 

Wendy

Joined Mar 24, 2008
22,236
Don't get discouraged, problems like these are how we learn.

Now you have a continuous power supply bus you will need to break it down.

I have written a lot of articles, and tend to draw the actual protoboard layouts to make it a bit easier. My time on and off the site has been a bit spotty due to health issues, but Riffa's suggestion about removing a few components at a time also has merit.

Each of the outputs of the 4017 is on one at a time, so each output will flash a LED for a short duration.

I'm going to steer you to an article I wrote that started as a tutorial for LEDs. It also has a police flasher section (links to follow). If you find it too intimidating don't worry about it, and we'll keep on working with you on your design. Note: the 4022 is very similar to the 4017, just fewer outputs.

LEDs, 555s, Flashers, and Light Chasers

Chapter 9....Light Chasers
Chapter 11.l.Making Patterns

Chapter 11 has a circuit very similar to yours, but it is done differently.

Like I said, if this feels like we're going over your head just ignore it and we'll focus on your layout.
 

bertus

Joined Apr 5, 2008
21,137
Hello,

I have drawn the needed connections on your breadboard photo:

breadboard_with_jumpers.jpg

Here are the wires that Bill_Marsden (AKA Wendy) and MrChips have told you.

Bertus
 

Thread Starter

archangeljess

Joined Dec 27, 2013
34
I have read all your recommendations. I will try removing the two 1n4148 diodes and will get back to you as soon as I'm done testing it.

Thank you,
Jess
 

Thread Starter

archangeljess

Joined Dec 27, 2013
34
I have tried R!f@@'s suggestion to remove the 1N4048 diodes. All is working well. The LEDs are turning on but not flashing. I also noticed that the 555 timer is getting hot. Is this normal?

Thanks
Jess
 

Thread Starter

archangeljess

Joined Dec 27, 2013
34
Hello,

I have drawn the needed connections on your breadboard photo:



Here are the wires that Bill_Marsden and MrChips have told you.

Bertus

I have already done this Bertus. However, the LEDs aren't flashing as it should be. I also tried R!f@@'s suggestion to remove the 1N4148 diode. When I tested it, the LEDs just light up no flashing. Any suggestion on what I should do next?
 

tubeguy

Joined Nov 3, 2012
1,157
I have already done this Bertus. However, the LEDs aren't flashing as it should be. I also tried R!f@@'s suggestion to remove the 1N4148 diode. When I tested it, the LEDs just light up no flashing. Any suggestion on what I should do next?
Double-check your wiring.
It looks like 4017 pin 8 is connected to V+ instead of ground.
4017 output pins 6,9 and 11 appear to be connected to gnd or V+.
These unused outputs should be left disconnected.
 
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