Multimeter Mastery: Components, Tracks & Voltage Checking Guide | Lesson 10

Team Tekno World ke free mobile repairing course mein aapka swagat hai! Main hoon Rakesh Chauhan, aur yeh humara Lesson 10 Multimeter Mastery: Components, Tracks & Voltage Checking Guide hai.

Pichle lesson mein humne Multimeter ke basics seekhe the. Aaj hum uska “Full Operation” karenge.

Aaj hum sirf components (purje) nahi, balki “Raaste” (Tracks) aur “Taqat” (Voltages) check karna bhi seekhenge. Mobile repairing mein 90% problems inhi teen cheezon mein hoti hain:

1. Component kharab hai (Short/Open).
2. Track (Raasta) toota hua hai.
3. Voltage (Power) nahi aa raha hai.

PART 1: Component Checking (Cold Testing)

(Phone OFF + No Battery). Ise Beep Mode par check karein.

• 1. Capacitor (C):
  • Check: Probes dono side lagayein.
  • Sahi (OK): Beep NAHI aayegi (Value 1).
  • Kharab: Dono side Beep = Short.
• 2. Coil (L):
  • Check: Probes dono side lagayein.
  • Sahi (OK): Beep aayegi (kyunki ye taar hai).
  • Kharab: Beep NAHI aayegi = Open (Toot gayi).
• 3. Diode (D):
  • Check: Diode mode mein ek taraf value, dusri taraf kuch nahi (1).
  • Kharab: Dono taraf Beep (Short) ya dono taraf 1 (Open).
• 4. Resistor (R):
  • Check: Ohms Mode (Ω) par value aani chahiye.
  • Kharab: Value “1” (OL) = Open.

PART 2: Track Checking (रास्ता चेक करना)

Mobile PCB par laakhon patli taambe (copper) ki lines hoti hain. Agar phone girne se koi line beech mein toot jaaye, toh supply aage nahi jayegi.

Kaise Check Karein? (Continuity Mode):

1. Apne Schematic Diagram (Lesson 34 mein seekhenge) mein dekhein ki Line Point A se Point B tak ja rahi hai.
2. Multimeter ko Beep Mode par rakhein.
3. Ek probe Point A par aur dusri Point B par rakhein.

[Image: इन-पोस्ट इमेज 2 (Track Checking Diagram)]

• 🔊 Beep Aayi: Rasta (Track) Juda hua (OK) hai.
• 🔇 Beep Nahi Aayi: Rasta (Track) beech mein Toot gaya (Broken/Open) hai.
  • Solution: Yahan hum ek patla “Jumper Wire” lagakar raste ko jod denge.

PART 3: Voltage Checking (Hot Testing) – [Most Important]

(Phone ON ya Charger Laga hua). Multimeter ko DC 20V par rakhein.

Kaali Probe hamesha Ground (-) par rakhein aur Laal Probe se check karein.

Mobile mein 6 tarah ke main Voltage Checking hote hain:

[Image: इन-पोस्ट इमेज 3 (Voltage Chart)]

1. VBUS (Charger Voltage)

• Kitna: 5.0V – 5.2V
• Kahan: Charging Jack, Sub-board, Charging IC ke input par.
• Kab: Jab charger laga ho.

2. VBAT / V-System (Battery Voltage)

• Kitna: 3.7V – 4.2V
• Kahan: Battery Connector, Power IC ke input par.
• Kab: Jab battery lagi ho ya phone ON ho.

3. VPH (Voltage Phone Power)

• Kitna: 3.7V – 4.2V (Battery jitna hi)
• Kahan: Charging IC se nikal kar poore board mein (Power IC, Network Section) jaata hai. Yeh phone ki Main Supply Line hai.

4. Buck Voltages (Step-Down)

• Kitna: 0.8V – 1.2V (Kam voltage, High Ampere)
• Kahan: CPU aur GPU ke paas lagi badi Coils par.
• Kaam: CPU ko chalana. (Agar ye nahi bana, toh phone Dead rahega).

5. Boost Voltages (Step-Up)

• Kitna: 15V – 30V+ (Bahut zyada voltage)
• Kahan: Light Section (Display Light) aur Flashlight section mein.
• Pehchan: Yahan voltage battery se bhi zyada hota hai.

6. LDO Voltages (Low Dropout)

• Kitna: 1.8V, 2.8V, 1.2V (Fixed constant voltage)
• Kahan: Camera, Sensors, Touch, aur Chhoti ICs par.
• Kaam: Sensitive parts ko “saaf” power dena.

Summary Table (Quick Guide)

💡 Aaj Ka Aapka Task – Lesson 10 (Comments & Forum)

1. Voltage Check: Charger lagakar VBUS (5V) check karein. Kya woh sahi aa raha hai?
2. Track Check: Multimeter se kisi bhi ground point se dusre ground point tak beep check karein (Ground track juda hota hai).
3. Comment: Aapke phone ki battery abhi kitne charge hai aur multimeter par kitne Volt dikha rahi hai? (e.g., 80% charge = 4.0V)
4. Forum: Agar aapko Buck aur Boost coil pehchanne mein dikkat hai, toh board ki photo Forum (forum.teamtw.in) par daalein.

Agla Lesson: Testing poori hui! Ab hathiyaar uthao. Agla lesson hai: “Lesson 11: Soldering Iron aur Solder Wire Ka Use (Soledring & Jumpering)”।