Continuity tester using android phone
2. 3.5mm jack or old headphone with mic
3. wire (multimeter probes is better)
Step 1: Cut the Headphone
Step 2: Find the MIC and GND Wires
Step 3: Connect 3K Resistor Parallel to the MIC and GND
Connect 3K resistor parallel to the MIC and GND and connect the probes wire and solder it.
Step 4: Finally Insulate the Wires
Step 5: Install Application to the Phone
Step 6: Testing.