Simple Help with Multimeter

Thread Starter

Chris15

Joined Apr 15, 2009
252
Hey
I just bought a multimeter for a circuit i blew up, i am confused but please bear with me. i have a circuit for an electronic Safe ES20, the supply voltage id 6V from 4 AA bateries, i modified it with a mains plug also 6V but 300ma and thats what i think destroyed it, where do i start with the multimeter, what setting and what components do i put it on, the circuit has 3 silicon diodes, lots of resistors, no electrolytic capacitors, a 14 leg chip and a 8 pin chip (not a 555)

Please help
 

mik3

Joined Feb 4, 2008
4,843
Hey
I just bought a multimeter for a circuit i blew up, i am confused but please bear with me. i have a circuit for an electronic Safe ES20, the supply voltage id 6V from 4 AA bateries, i modified it with a mains plug also 6V but 300ma and thats what i think destroyed it, where do i start with the multimeter, what setting and what components do i put it on, the circuit has 3 silicon diodes, lots of resistors, no electrolytic capacitors, a 14 leg chip and a 8 pin chip (not a 555)

Please help
You destroyed it because the wall adaptor you have is unregulated. This means that to output 6V the device must draw 300mA otherwise it will output a voltage higher than 6V (up to 8.5V). When powering electronic devices from wall adaptors take care of them to be regulated.
 

Thread Starter

Chris15

Joined Apr 15, 2009
252
Yeh but how do i fix the circuit? there is a component that is screwed so how do i find it, a diode a resistor?
 

SgtWookie

Joined Jul 17, 2007
22,230
I'll bet that at least one of the IC's is a microcontroller, and by applying more than 6v to it, you've fried it.

Even if you can read the numbers from the IC and order a new one, it won't come programmed.

It's not likely that you'll be able to get the program code from the manufacturer.
 

CDRIVE

Joined Jul 1, 2008
2,219
I'll bet that at least one of the IC's is a microcontroller, and by applying more than 6v to it, you've fried it.

Even if you can read the numbers from the IC and order a new one, it won't come programmed.

It's not likely that you'll be able to get the program code from the manufacturer.
Oops, I just took a peek at the link he posted. I thought that this was a kit circuit. Guess not.
 
Last edited:

Thread Starter

Chris15

Joined Apr 15, 2009
252
Ok thanks SgtWookie and everyone else ill just buy a new safe, but i have this lump of steel bolted to my desk with no curcuit just a key, is there any circuit i could build simply that would an electronic entry?

Chris
 
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