Upgrading Old Multimeter With Buzzer

by LordWader in Circuits > Tools

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Upgrading Old Multimeter With Buzzer

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I have been using this multimeter since I know about electronics. I think that it is manifactured in 1974 so I am 1 year older than my multimeter. It is a durable tool and i decided to upgrade it with buzer circuit.

Step: 1 I Found Buzzer Circuit on Net and Used It.

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Part list for buzzer:
1. buzzer
2. led diode
3. transistor BC547B
4. resistor 220 ohm
5. resistor 330 ohm
6. resistor 1M ohm
7. switch
8. 3v battery, I used multimeter battery.

Step 2: Dismount and Clean Inside

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I dismounted it and cleaned all the contacts.

Step 3: Placing New Circuit Inside

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After cleaning I drilled holes for connectors for probes. Because there wasn't enough space for connectors I moved the fuse into fuse holder and use empty space for battery, where I put buzzer too.

Step 4: Replacing Probe Connector

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Old probe connector was broken and I replaced it.

Step 4: Testing the Multimeter

Final tests.

And we are good to go.