Introduction: Upgrading Old Multimeter With Buzzer
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: Step: 1 I Found Buzzer Circuit on Net and Used It.
Part list for buzzer:
2. led diode
3. transistor BC547B
4. resistor 220 ohm
5. resistor 330 ohm
6. resistor 1M ohm
8. 3v battery, I used multimeter battery.
Step 2: Step 2: Dismount and Clean Inside
I dismounted it and cleaned all the contacts.
Step 3: Step 3: Placing New Circuit Inside
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: Step 4: Replacing Probe Connector
Old probe connector was broken and I replaced it.
Step 5: Step 4: Testing the Multimeter
And we are good to go.