fireflyva wrote:Hey guys - I'm new at this and don't want to electrocute myself so I thought I'd better ask.
I have an old laptop power cord that is rated at 19.5 v DC @ 3.16 A that I have used to provide power to my breadboard. Since most of the projects require 9 volts, I placed a guitar pot in between the power cord and the breadboard, and using my multimeter I dialed the pot down to get 9 volts at my breadboard. I've read on this forum somewhere that too much power is generally not a problem because the circuit will only "pull" what it needs, and that power won't be "forced through" the circuit causing anything to burn up.
Question: I'm not likely to cause any harm providing power this way, am I? I get tired of buying 9 volt batteries.
Thanks for your help.
i'm not an electronics graduate but i'd say for the sake of £5 don't risk frying yourself or your circuits and buy something like this:http://www.ebay.co.uk/itm/AC-DC-600mA-Universal-Mains-Plug-Power-Supply-Charger-Adapter-Adaptor-3v-12v-/351180450991?pt=UK_ConsumerElectronics_PowerAdaptors_SM&hash=item51c3fc6caf
you will get all the voltages you'll ever need 3V, 4.5V, 5V, 6V, 7.5V, 9V, 12V (these things are pretty accurate) with the option of reversible polarity (not sure if this one has but mine is similar and does, worth checking), you can also use it with a daisy chain for your effects, and it will work for anything else around the house that ever needs any kind of mains power supply.
don't take risks with your health for a few pounds.