I'm an electrical student in my second year and I'm using a breadboard for multiple lab classes. I'm thinking that my breadboard is starting to fail inside and I'm having a hard time troubleshooting circuits and getting some weird result. Today I had a JK Flip Flop hooked up as a Frequency divider and output on the oscilloscope was coming out a extremely high frequencies and there was no amplitude. One second the output would show up and then another second the output would disappear. I'm wondering where to buy a high quality breadboard since the ones we used to get are not made anymore. The breadboard I have has a hard plastic back so you can't push leads through the backing by accident very nice feature. Now that my circuits are becoming more complicated I don't want to have a breadboard that fails me in lab class. Any suggestions would be great, thanks.
4 Answers
I have used plug in breadboards for many decades. I own dozens of them. They are a marvellous tool and are well worth using if used with due care and intelligence.
However, they can also cause unexpected problems. The tradeoffs are worthwhile overall but you must always be aware of the dangers.
Breadboard quality varies. Price is some indicator of quality but obviously some people will sell you cheap junk at whatever price they can get you to pay. But, if you can buy a given brand anywhere at much lower than average price it is liable to be suspect.
Be prepared to use them with care, take care of how you insert wires into them and be realistic in what you expect of them.
NEVER plug larger leaded components into them. One forced insertion may weaken the spring at that point forever. If you want to use larger leaded components, solder a small extension of thinner wire onto them. The venturesome could wrap many turns of wire around a component lead to remove the need to solder. This would often work well - but YMMV*, as always.
Use smooth plated wires without nicks. Do not use bar copper wire which can corrode. Do not use abrasive wires (nicked etc)
Be aware that the strips have high capacitance between adjacent rows - circuits that are adversely affected by a picoFarad or few of interstrip coupling are not good candidates.
Do not pass high currents through the breadboard. It may cause no problems now or in future. Or may.
Be aware that wires may pull out or short or conspire against you.
Components with very small diameter leads (eg some TO92 transistors) MAY make poor contact. I usually have no problems with TO92 style transistors.
Even Olin says breadboards have their place.
So they must be OK.
:-)
Your flipflop problem MAY have been caused by a floating set or reset piu - ie not a fault of the breadboard.
What frequency was the flipflop operating at?
Frequencies of a few MHz may be OK.
10 MHz maybe.
Higher than that is "adventurous".
*YMMV = Your mileage may vary ~~= "Are you feeling lucky, Punk?"
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\$\begingroup\$ Absolutely! Despite drawbacks, breadboards are the absolute fastest way to get many things done, the easiest way to "try stuff" without worrying about rework, and just too valuable of a tool to permanently shelve. \$\endgroup\$ Commented Oct 25, 2012 at 13:17
Personally I would toss the flakey breadboard in the thrash and never look back. These things will always be a pain. You would be far better off building your circuits on pad-per-hole prototype board with solder and wiring. Much more stable and you'll reduce your time chasing nonsense ghost problems down to next to nothing.
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\$\begingroup\$ I agree, or even debugging it too. \$\endgroup\$ Commented Oct 25, 2012 at 4:30
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\$\begingroup\$ One pad per hole board is junk. You're better off with prototype PC board that has traces spanning islands of multiple holes, or long strips of holes. \$\endgroup\$– KazCommented Oct 25, 2012 at 19:52
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\$\begingroup\$ @Kaz - The type of prototyping board I use has plated through holes in a continuous grid across the whole board with 2.54mm spacing. The board is to hold the components and connections are efficiently made using wires. Strips of interconnected holes on protoboards (especially non plated holes) in my experience is junk. So I guess it comes down to user experience and what they found that works for them. \$\endgroup\$ Commented Oct 29, 2012 at 8:12
Adafruit has great prototyping stuff at very reasonable prices.
They have a really nifty clear breadboard that has power rails that snap off so that you can snap together multiple board for larger projects. And since it's clear you can see the junctions inside. Not that you would be able to tell from that if a junction was failing. But it's still pretty nifty.
As Russell mentioned, using good wire will help in avoiding damage to your breadboard. Adafruit sells wires with nice ends molded on for only a couple of bucks. So if an end gets nicked, bent or damaged, you can toss it without breaking the bank.
As others have mentioned, going to a pad-per-hole type board and using solder has many advantages. While somewhat impractical for course work where you'll be changing it up every week, they're great for personal projects. Or if you want to solidify a certain circuit you breadboarded for class to show the grandkids down the line. I still wish I had the ADC I build from discrete components in college on a breadboard.
In that vain, I highly recommend Adafruit's Perma-Proto boards. They are fantastic to work with. And since they have the same layout as a breadboard, transferring a circuit is very easy.
No affiliation, just a very satisfied customer.
I usually start on a breadboard, but as soon as something starts to behave funny, I switch to copper-clad board: EE pros - how do you prototype?
I hate those pad-per-hole boards as they usually are hard to rework.
Just keep in mind that if something does not work, it might be your circuit, but it might be a breadboard as well. Or if circuit kinda works - not necessarily everything is ok as you might be getting capacitive coupling thru the breadboard for the missing connection.
