Step 5: Test it!

Picture of Test it!
After you had built your power supply, test it with your multimeter to make sure they are no solder bridges.

After you tested it, put it in a plastic box or something to protect you from shocks.
But do not operate the power supply like I did, it is very dangerous because of the mains voltage on the transformer, you or somebody will get badly shocked!

My power supply has 11.73v output, not too bad, I don't need it to be exactly 12v...
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N3v3rm0r34 years ago
How much current can that power supply give? I need 800mA....
brady9115 years ago
so do you connect the GND connection to the negative lead? i know this sounds like a stupid question maybe...
 Like magic, an LED appears!

Can you tell me how and where it was added? I noticed a (limiting?) resistor, too.

Maybe add it to the schematic, please.

Also, I am using your project as a guide to modify a circuit I put together to convert the 18VAC output from my home's Bell Transformer so as to power a LARGE 12VDC Bell (ARCHER 275-498 - Old RS Bell) that worked great off my car battery, but not so much off the 18VAC Bell Transformer through a diode package from RS. 

I thought the capacitors and regulator might help - hence my interest. 

BTW, if I am on the wrong track and need something entirely different, let me know that, too please!

Thank you
ir_syed5 years ago
Hello.i want ask 3 i want to vary voltage 12v ??should i use a variable resistor to control it??and where suppose i should put the variable resistor in the circuit???...anyone can help me...plezz
codex6535 years ago
is that 12v ac or dc?? i'm looking to make an 12v ac power supply from a battery to power some of my projects as the mains seem to be quite too high! :)
Plasmana (author)  codex6535 years ago
It is DC output.