9V power supply for breadboarding?

[monksanto]

Hi, just wondering what is the best way to provide power for my breadboard circuits. At this stage I am just fooling around with 9V pedal circuits, maybe a few 9V low-wattage amps, so I'm thinking a variable bench power supply is a bit overkill? How would I connect a 9V DC wallwart to a breadboard?

Thanks!

[roseblood11]

solder two jumper wires to a dc jack???

I just use a battery, it's the cleanest power supply of all

[JustinFun]

at its simplest, if you don't mind sarcificing a 9v adaptor for breadboard use only, you could just cut the end off your adaptor and solder a couple of banana plugs on.

If you want to keep your adaptor intact, then you'll need to solder two leads to an AC adaptor socket - either to banana plugs or just use solid core wire to stick straight in the breadboard.

You could mount the socket on a piece of vero and then it should be able to stick straight in to one of the slots on your breadboard.

However it's worth considering building a little breakout board that will take a 12v adaptor and give you clean regulated 9v, 18v and -9v. There are schematics all over the web - i've got a verified layout of my own which I will stick up here when I can find it!

[deadastronaut]

i use my (good) pedalboard supply...after all that's what its going to be used with..(unless you like batts of course)

all my breadboards are true bypassed (toggle not footswitch ) in/out jacks, led, dc socket...so it is an open heart surgery pedal without the box.

just so that when you finally build it you know exactly how it will behave..

[monksanto]

Thanks! I think I will get a wallwart & strip the ends.

it's worth considering building a little breakout board that will take a 12v adaptor and give you clean regulated 9v, 18v and -9v. There are schematics all over the web - i've got a verified layout of my own which I will stick up here when I can find it!

Yes please, I am interested to see it.

[deadastronaut]

don't strip  the wallwarts ends, just use a dc socket (even one of those metal dc soxkets that are useless for anything else) with wires to your board. (watch polarity)

build this true bypass board..makes real life testing/prototyping easy....not the neatest, but it was an early one..





diagram.

[Ice-9]

I use the same breadboard as Rob above. I think it was from maplins at £10. Anyway there is a nice useful corner at the right where I have mounted one of my true bypass pcbs to, which has all the power and jacks mounted to it with the power and fx in/outs running to the coloured connectors on the left for easy use. t can be used with either batter or psu.

[deadastronaut]

neat little TB board man...tidy.

[bcalla]

I have a bench top supply, which I use to power my testing rig, which has jumpers to my breadboard.  Both are mounted to an extra shelf from a small bookcase.

[GibsonGM]

Very nice, guys.  Has anyone run their wall warts thru a regulator?  Just to 'make it real', y'know.    I use a battery very often, or my 0-30V adjustable 5A benchtop regulated supply.   Yes, it's overkill, but lets me do anything and everything, from running a CB to starving a fuzz!

If I was gonne do wall wart (and have in the past), I'd look into a regulator with the filter caps to make sure you get clean power.  Or use a regulated wall wart...

[smallbearelec]

Hi--

An unregulated wall-wart:

http://www.smallbearelec.com/servlet/Detail?no=1004

is inexpensive, but you'll be wondering why you get a lot of hum in your output. These bricks need a three-terminal regulator and additional filter capacitors to reduce ripple current. There are many on-line references that describe how to do the add-on. If you go this route, a 12-Volt wall wart is better, because it gives the regulator more headroom to work with. Or you can spend the extra $$ for a purpose-made brick like this:

http://www.smallbearelec.com/servlet/Detail?no=1466

Or you can build a Small Wart:

http://www.smallbearelec.com/Projects/SmWart/SmWart.htm

Regards
SD

[gjcamann]

1-spot - 1700 mA, well regulated, what more could you need?

[therecordingart]

Maybe it's just me, but some of my biggest idiot moves happen on a breadboard. If you are going to be using a wallwart type supply make certain you build in some sort of short protection. Otherwise you can't beat a 9v battery.

[Seljer]

Another option is to build a little module that sits nicely onto the breadboard with a jack + rectifier + voltage regulator + filter caps: http://www.electronics-lab.com/blog/wp-content/uploads/2008/02/main1.jpg

Maybe it's just me, but some of my biggest idiot moves happen on a breadboard. If you are going to be using a wallwart type supply make certain you build in some sort of short protection. Otherwise you can't beat a 9v battery.

I've burnt out a quiet a few traces and many components on my breadboards  But the 78XX regulators seem to be pretty good at handling short circuits and the supply seems to survive. I've so far only managed to kill one by accidently feeding it a negative voltage when I was doing something with a bipolar supply (but had not bothered to add the extra protection diodes to the regulator).

[armdnrdy]

I used to use a DC brick to power my breadboard but found that even 9-18VDC was limiting.
A good number of the projects I work on require a voltage greater than 9 volts and/or a bipolar supply.

I found the need early on for an adjustable dual bench power supply.

It all depends on the type of things that you build. A dual supply can be overkill but....I couldn't get by without it.





There were quite a few other things that I needed as well. I was in test equipment build mode for a few months.
All of these projects were worked out from information I found on the net....nothing to program. All CMOS technology.

[joelster]

I wired up a a little circuit on a piece of perfboard with an LM7809 9vdc voltage regulator and put it into a Hammond 1590A box. I feed that with a 12 volt wall wart from goodwill. Puts out 8.9VDC IIRC. I'll try to post pics later.

I originally built it so you could power a pedal board with a LiPo battery (14.4VDC) but have only used it on my workbench cuz it's so damned handy.

An easy option might be to just get a One Spot. $20 or so I think. Those put out 1 amp at 9VDC.

[GGBB]

I built something like a Beavis breakout box (http://beavisaudio.com/bboard/images/io_diy.jpg) and power it with a 9V battery via a DC plug adapter.  This powers my breadboard most of the time, but when I'm working on the power filtering section or doing my final testing before building, I'll plug in a couple of different wall-warts (a good quality regulated and at least one cheap quality unregulated) to the breakout box to see if they cause any noise.

[GibsonGM]

Jeez, Larry, we might as well let 'em know that you can find a nice analog oscilloscope from the 80s on Fleabay for < $150, too!     Nice equipment you have.  )   
I use an old PC with a function generator program to do that job, up to 22kHz - I run the output into a small opamp AC amplifier to get it up to where I want it, 4VAC max.   One of these days I'll be getting an actual generator.

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Yes, the 78XX series regulators have short-circuit protection built in.    No matter which way you go, unless you're on battery you'll want to make sure your power supply is filtered and regulated...

[armdnrdy]

Jeez, Larry, we might as well let 'em know that you can find a nice analog oscilloscope from the 80s on Fleabay for < $150, too!     Nice equipment you have.  )   

I actually have an old analog oscilloscope from the 80s 70s that I bought through Craigslist for $20. (I didn't build my own)

I looked into the PC oscilloscopes as well as the PC function generators......I'm a bit old school, (and old) I like to build things, and my office desk with my PC is on the other side of the room from my work bench.

[davent]

 More often then not it's been a 9v with a battery snap into a Beavis-like box. Recently overhauled an old smulti-voltage bipolar supply and it's my source now.

Adjustable, bipolar regulator, breadboard module.