AC/DC Adapter as Benchtop power supply.

[gatoruss]

I am an absolute noobe. I would like to make a power supply for my breadboard. A nearby store sells used AC/DC adapters for very little (some as cheap as a $1) - wide assortment of voltage and current output. I was thinking that could use the adapter as a power supply for my breadboard. I researched this on the net and have found some projects that do just this...with voltage regulator, etc...(see for example **broken link removed**).

My question is, is this safe to do. The idea of playing around with AC concerns me...I am hoping that it is relatively safe as I will be connecting the DC side to breadboard.

Thought, suggestions, advice?

Thanks.

 

[kchriste]

Pretty safe. The AC/DC adapter is a transformer, usually with a built in rectifier and cap, which provides isolation from the AC line voltage.

 

[eblc1388]

Check their output voltage before use. They are good if your circuit has its own voltage regulator, e.g. 7805 or 78L05 etc...

You will be surprised that one marked 9V output could give out more than 12V.

 

[gatoruss]

Thanks.

I am just beginning to play around with some projects (been messing around with a pic). Thought that the wall wart set up would save some battery use (currently using a 9 volt) and would be fun/instructional to build. Got the idea https://www.sparkfun.com/commerce/present.php?p=BEE-1-PowerSupply. I realize that this link deals with avr mcu and that set up will not program pic - but thought that power supply could be used for low voltage/low current circuits that would otherwise be using 9 volt battery.

A few weeks back I was reading a tutorial on building a bench top power supply that had a lot of cautionary info on how not to kill yourself. Being a newbie I heeded this advice and steered clear of that kind of project. When I came across the wall wart idea, it seemed like a good approach. I thought it best to ask around first, however, and to get some advice on whether this was a safe thing to be messing with.

 

[audioguru]

30 seconds ago I answered this thread on another website.

 

[gatoruss]

I am sorry. Is it bad form to post same question on multiple websites? I am relatively new to both and do not have a good gauge as to which site might be better for which topics.....

 

[Pommie]

30 seconds ago I answered this thread on another website.

That proves that questioner and answeree both frequent multiple websites.

Mike.

 

[gatoruss]

Thanks...I am going to give this a try.

 

[adaminc]

After you get used to this, you could try using a computer power supply. It will give you (depending on the PSU) +5V, +12V, -5V, -12V and sometimes +3.3V