Where to find beginner projects

atferrari

Joined Jan 6, 2004
4,764
Wire the circuit on the breadboard that didn't work and use a voltmeter to troubleshoot the problem. If you suspect bad breadboard contacts, you can use a continuity checker on the unpowered circuit.

You need to use an oscilloscope if the signals are changing too quickly to use a DVM.
When still dealing with basics like the abvo, you could also make it running very slowly. Helped me with my first TTL circuits.
 

dl324

Joined Mar 30, 2015
16,846
When still dealing with basics like the abvo, you could also make it running very slowly. Helped me with my first TTL circuits.
I used the same technique when I was designing a variable clock generator and the only test gear I had was an analog voltmeter. The clock generator also had an adjustable supply to power test circuits.
 

Wendy

Joined Mar 24, 2008
23,415
learning the art of troubleshooting is a huge part of learning electronics, Treat this as a major learning opportunity because it is.
 

Thread Starter

Levi Titan

Joined Feb 10, 2019
6
Wire the circuit on the breadboard that didn't work and use a voltmeter to troubleshoot the problem. If you suspect bad breadboard contacts, you can use a continuity checker on the unpowered circuit.

You need to use an oscilloscope if the signals are changing too quickly to use a DVM.

Thank you so much for this post. The first time I skimmed through it and thought it's too early for me to do all that and I can't afford to pay for an oscilloscope. Then I read through and it looked up a continuity checker. I realized the buzzer that came with 1 of my kits is a continuity checker. I checked the whole circuit for continuity between the wires and components. Then realized it couldn't be the board because of continuity through it. I gave up and the answer was staring me in the face. The capacitor has a negative side. I learnt from another site that it doesn't matter which way they're connected like resistors, but there's obviously specific capacitors with a polarity.
 

dl324

Joined Mar 30, 2015
16,846
The capacitor has a negative side. I learnt from another site that it doesn't matter which way they're connected like resistors, but there's obviously specific capacitors with a polarity.
Electrolytic capacitors are polarized and don't take to reverse polarity well.

From Cornell Dubilier's Aluminum Electrolytic Capacitor Guide, page 9:
upload_2019-2-13_7-36-3.png

This applies to all electrolytic caps, e.g. tantalum.

Ceramic, mylar, mica, etc are non-polarized.
 
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dl324

Joined Mar 30, 2015
16,846
The first time I skimmed through it and thought it's too early for me to do all that and I can't afford to pay for an oscilloscope.
Depending on the frequency involved, a DMM can be used to troubleshoot a 555 timer circuit.

Here's some timer circuit I had handy (it was likely for another AAC member):
upload_2019-2-13_8-8-48.png

The first thing that I'd check is the voltage on the timing cap. It should either be charging or discharging and a DMM could tell you that. If it isn't, then look for problems with charging/discharging.

If it's not charging, look for connection issues with R1 and R2. If it's not discharging, look for issues involving R1 and it's connection to the Discharge pin.

Note that the capacitor symbols indicate C1 is polarized and C2 isn't.
 

Thread Starter

Levi Titan

Joined Feb 10, 2019
6
I'm thinking of buying the book "Starting Electronics" - Keith Brindley. Does it cover the basics in enough detail and does it cover enough basics for the beginner. I want a strong foundation and shallow knowledge of the breadth of this subject.
 

BR-549

Joined Sep 22, 2013
4,928
If you want a clear understanding of the fundamentals......you can not beat "Electronic Communication" sixth edition by Shrader.

Around 10 bucks on Amazon.
 

bwilliams60

Joined Nov 18, 2012
1,442
Electronics for Dummies is an easy read but I agree with others on Forrest Mims. His books are plain ans simple and his hand drawings are legendary in my books.
 
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