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[on:]

Hi,

I bought a starter kit on Amazon and the little breadboard that came with it does have the "channel" running down the middle but the two rows along the outside edge that seem to be where the higher voltage power connects aren't there like I see in other people's projects.

My son and I were able to do the blinking light project with it but we're now trying to do a three LED cross fade project and all the boards I'm seeing in the tutorials have the outside pair of rows.

I remember reading that these rows are good because the connections under the rest of the holes on the breadboard aren't strong enough to handle the power.

Clearly I'm a newbie but hoping to build the project without getting a new breadboard. The below link shows what we have. Any insight would be appreciated and any links you know of showing wiring without the better breadboards for 3 separate LED's would be appreciated if there's any significant difference.

It's the one in the group shot, not the separate sht of the breadboard.

http://www.amazon.com/gp/product/B004HL44MI/ref=oh_details_o04_s00_i01

Thanks!

[Reply #1 on:]

I bought a starter kit on Amazon and the little breadboard that came with it does have the "channel" running down the middle but the two rows along the outside edge that seem to be where the higher voltage power connects aren't there like I see in other people's projects.

I guess you are comparing your breadboard to this one:

And you are wondering what those additional rails at the top and bottom of it are for.

Well, consider that the underneath the holes there are traces that connect bunch of holes together following this scheme:


It's simple as that. The holes in the middle part are connected together with vertical rails (the black ones) in groups of five at once.
The two horizontal hole lines on top and those at the bottom (both couple of hole lines marked with red/blue strips associated with a +/- sign meaning positive and negative voltage) are connected with horizontal rails. Those rails are generally used for connecting a single voltage supplier to the entire board and sharing it with each component that needs it.

I don't think those horizontal +/- rails are physically any different than the others (the inner black ones), I don't think they can support more electrical power at all. This geometry is being used for making life easier in building prototypes and nothing more :-)

So I'm positive any scheme you find on those tutorials may be ported with minimal modifications to this breadboard of yours too :-)
 

[Reply #2 on:]

I don't think those horizontal +/- rails are physically any different than the others (the inner black ones), I don't think they can support more electrical power at all.

Yep. If you pull the backing off the breadboard you'll see the contacts are identical.

[Reply #3 on:]

I remember reading that these rows are good because the connections under the rest of the holes on the breadboard aren't strong enough to handle the power

That is wrong, they are both the same. Just chain the power from one track to the next, or have a couple of vertical lines connected to power and link with jumpers to where it is needed.

[Reply #4 on:]

Thanks for taking the time Robitabu for explaining all that and posting the pics. That exactly what I was wondering and this helps a lot. Thanks Chagrin and Grumpy Mike as well for shedding more light on this. really nice of you to help.

[Reply #5 on:]

I don't think those horizontal +/- rails are physically any different than the others (the inner black ones), I don't think they can support more electrical power at all.

Yep. If you pull the backing off the breadboard you'll see the contacts are identical.

If you pull off the backing this is what you see (I tried to the remove the breadboard after using the adhesive on the breadboard, and pulled out the pins):

[Reply #6 on:]

I should mention, the small breadboards without with the external red/black power rails are useful if you get a proto shield, as it fits directly in between the rows of pins.  You don't have the convenience of having the power and grounds near the rows, and you will have to bring them forward, but if you switch from project to project, you can put all of stuff for one project on the breadboard and shield, and just remove it to switch to the next project.  For example, this is a revision of my telegraph shutter key:


However, if I'm doing breadboard work without the proto-shield, I tend to prefer the shields with the power rails.

[Reply #7 on:]

Thanks Michael. That helps!

Bob