You’ve found a cool 555 timer project online or in my book, procured all of the parts, wired them up on a breadboard, and are now ready to power up your newly made creation. Time for the moment of glory. You slide the power switch on and… nothing, it’s not working how you expected, or worst case scenario – the magic smoke escapes one of your parts.

It’s happened to the best of us and will continue to do so. These have been my four most common 555 timer circuit mistakes, and are common in most other breadboard projects.

Wiring/Placement Mistake

I would say this is the most common cause for error that I have experienced, especially with breadboard circuits. All it takes is for one wire or part to be off by one hole on the breadboard, or you have a particular component flipped around backward, and your circuit will probably be rendered inoperable.

Solution: Double, even triple-check your wiring. Ensure all chips and polarized components are placed in the correct orientation. Methodically follow the current flow of the schematic in comparison to your breadboard circuit.

Wrong Component

Almost a tie for the most common problem I’ve experienced is using the wrong component. An incorrect value of a resistor, capacitor, etc., is easy to do with small, sometimes cryptic labels on parts.

Solution: Similar to the wiring mistakes, carefully check each component label to make sure it’s the correct value.

Low Battery Voltage

Your circuit works perfectly once, but not the second time you test it, even without changing anything. The timing is off, LEDs are barely lighting, what the heck is going on? After checking many iterations of a circuit or leaving it on for a while, that 9-volt battery may only be at 7 volts, and things may start to get a bit wonky. The 555 is fairly immune to supply voltage differences. However, when a battery nears the lower end of its capacity, the increase in internal resistance of the dying battery reduces the available current to the point of rendering your circuit or device useless.

Solution: If you notice any of the issues mentioned above, fire up your trusty multimeter and make sure the battery voltage for your circuit is at an acceptable level.

Capacitor Leakage

After thoroughly troubleshooting every tip mentioned above, the timing cycle of your project “hangs.” An LED should turn on and then off in monostable mode but instead stays on, or your astable mode circuit doesn’t oscillate from one state to the next, etc.

If your circuit uses a large value timing capacitor (usually for longer timing periods), the culprit of the behavior described above could be a leaky capacitor. What is capacitor leakage? When basic electronics are taught using the water (hydraulics) analogy method, a capacitor is usually represented by a pipe with a perfectly sealed flexible rubber diaphragm in the middle that prevents water from passing through.

To use that analogy to describe capacitor leakage, the diaphragm isn’t perfectly sealed, and a small amount of water (current) does leak through. Large electrolytic capacitors are known for having a higher leakage current than most other types. This can cause issues for time-sensitive circuits.

Another way to visualize leakage current is in the diagram to the right. Imagine a resistor in parallel with the capacitor allowing a small amount of current to pass.

I have had a brand new 50-volt, 1 uF electrolytic capacitor by one manufacturer only charge up to 2 volts when 9 volts were applied due to high leakage current. All of my other caps by different manufacturers with the same ratings worked fine. It took me a while to figure out what was going on.

Solution: For more critical timing applications tantalum or Mylar and other film type caps usually work best. If you have to use electrolytic caps, at least use low tolerance, high-quality ones. You can usually find the leakage current specs on the manufacturer’s data sheet.

Wrapping Up

These are the most common errors I’ve run into while working with breadboard circuits. How about you? What have been your biggest 555 timer circuit mistakes? Give everyone a heads up of what to look out for in the comments below!

The post Four Biggest 555 Timer Circuit Mistakes appeared first on Bent-Tronics.

In this video, I show what the completed projects from Chapter 7 should look like.

Buy the book here.
Buy the complete parts kit here.

The post My 555 Book, Chpt. 8 recap: Bonus Mode appeared first on Bent-Tronics.

In this video, I show what the completed projects from Chapter 7 should look like.

Errata:
Project 5 parts list – Optional caps C4 and C5 are shown in the schematic and breadboard layouts, but not listed in the parts list. Both should be .01 uF

The post My 555 Book, Chpt. 7 recap: Audible Anarchy with the Atari Punk Console appeared first on Bent-Tronics.

In this video, I show what the completed projects from Chapter 6 should look like.

Buy the book here.
Buy the complete parts kit here.

The post My 555 Book, Chpt. 6 recap: More Mode Mixing appeared first on Bent-Tronics.

In this video, I show what the completed projects from Chapter 5 should look like.

Buy the book here.
Buy the complete parts kit here.

The post My 555 Book, Chpt. 5 recap: Mixing Modes appeared first on Bent-Tronics.

In this video, I show what the completed projects from Chapter 4 should look like.

Buy the book here.
Buy the complete parts kit here.

The post My 555 Book, Chpt. 4 recap: Basic Monostable Mode appeared first on Bent-Tronics.

In this video, I show what the completed projects from Chapter 3 should look and sound like.

Buy the book here.
Buy the complete parts kit here.

The post My 555 Book, Chpt. 3 recap: Basic Astable Mode appeared first on Bent-Tronics.

In this video, I explain the basics of breadboards, and how to transfer a simple schematic to a working circuit on a breadboard.

Buy the book here.
Buy the complete parts kit here.

The post My 555 Book, Chpt. 1: How to use a breadboard, transfer schematics to a working circuit appeared first on Bent-Tronics.

Things have been a little quiet on the blog, but behind the scenes, I’ve been a writing/editing/formatting/coding/building/designing/marketing/coffee-drinking machine! Two years ago I had an idea to write an e-book about the 555 timer. That has now manifested itself into a full-blown print book, Kindle book, and a complete parts kit for the projects listed inside.

The Ultimate Beginner’s Guide to the 555 Timer: Build the Atari Punk Console and Other Breadboard Electronics Projects. Yes, it’s a mouthful, but it gets the entire scope of the book across in the title.

The book is available on Amazon here.

I also collaborated with Jameco to assemble a full parts kit with all of the components required to complete the projects listed in the book. The parts kit is available from Jameco here.

The official homepage for the book, which will include videos of each chapter and project in the book, plus much more, is here: bent-tronics.com/555-timer-circuit-book

Check out this video of me opening up the book and kit for the first time and a quick overview of each.

Here’s the Amazon blurb:
Unlock weird noises, hypnotic lights, and master the 555 timer.
Buy the print version of this book first to get the Kindle version for just $0.99! (not available in all countries)
This fast-paced, easy-to-follow book teaches you how the 555 timer works with step-by-step instructions and hands-on projects. Whether you are an electronics enthusiast or a beginner, this DIY guide shares simple tricks and hacks to put the 555 timer into action. FULL-COLOR illustrations show you how to transform circuit schematics into real-world working examples on a standard breadboard – no soldering required! High-resolution oscilloscope screenshots reveal detailed views of complex waveforms not able to be seen with the human eye. Advance your skills by completing the included projects so that you can create your own unique designs. A complete parts kit is available too!
You will learn how to:

• Use a breadboard
• Utilize the 555’s pins
• Trigger “one-shot” mode
• Blink an LED
• Generate noises with an oscillator
• Create a frequency divider
• Make a bistable flip-flop
• Source and sink current
• Build and understand the Atari Punk Console

The post My new book: The Ultimate Beginner’s Guide to the 555 Timer appeared first on Bent-Tronics.

Until now there hasn’t been much on the interwebs on how to set up the Dangerous Prototypes Bus Pirate for decoding MIDI data.

Here’s my contribution, which happens to be on International Talk Like a Pirate Day.

Bus Pirate on Amazon: http://amzn.to/2dcZ9uS
Bus Pirate on SparkFun: http://bit.ly/2bKjZfT
TyMkrs MIDI In Me: http://bit.ly/2cihEdA

The post Video: Talk MIDI with the Bus Pirate on Talk Like a Pirate Day appeared first on Bent-Tronics.