120W Power Amplifier Circuit using Transistors 2N3055 and MJ2955

120W Power Amplifier Circuit using Transistors 2N3055 and MJ2955

120W Power Amplifier Circuit

This 120W Power Amplifier circuit is designed by using transistors like 2N3055 and MJ2955 which is well-known Power transistors pair of NPN and PNP polarity. these transistors working voltage up to +/- 50V symmetrical power supply with minimum 3A electric current should be used for maximum performance of 120w power amplifier circuit

120W Power Amplifier Circuit Diagram

120W Power Amplifier Circuit Diagram

120W Power Amplifier Circuit Components:

Transistors

 

  1. 2N3055 (substitution: MJ15003 or 2N3772) : 2 no.s
  2. MJ2955 (substitution: MJ15004 or 2N3771) : 2 no.s
  3. TIP42: 2 no.s
  4. TIP41: 1 no.
  5. 2SC2229 or 2SC2230 or C1573: 2 no.s
  6. A1015 or A872 or A733: 2 no.s

Capacitors

 

  1. 100uF/50V electrolytic capacitor: 2 no.s
  2. 470nF (474) nonpolar polyester capacitor: 1 no.s
  3. 100pF (101) nonpolar ceramic capacitor : 2 no.s
  4. 470pF (471) nonpolar ceramic capacitor : 2 no.s
  5. 10pF nonpolar ceramic capacitor: 2 no.s
  6. 100nF (104) 100V nonpolar polyester capacitor : 2no.s

Resistors

 

  1. 0.33 Ω (5W) : 4 no.s
  2. 10 Ω to (1W) – brown, black, black: 1 no.s
  3. 100 Ω (1W) – brown, black, brown: 2 no.s
  4. 33 Ω (1/4W) – orange, orange, black: 1 no.s
  5. 150 Ω (1/4W) – brown, green, brown: 3 no.s
  6. 10KΩ (1/4W) – brown, black, orange: 1 no.s
  7. 1KΩ (1/4W) – brown, black, red: 1 no.s
  8. 4.7KΩ (1W) – yellow, violet, red: 1 no.s
  9. 68KΩ (1/4W) – blue, gray, orange: 1 no.s
  10. 56KΩ (1/4W) – green, blue, orange: 1 no.s
  11. 33KΩ (1/4W) – orange, orange, orange: 1 no.s
  12. 3.3KΩ (1/4W) – orange, orange, red: 2 no.s

Diodes

  • 3A Diode 1N5404: 2
  • 1A Diode 1N4007 : 3
  • Zener diodes between 20 and 24 volts: 1

Others

  • 3A fuse
  • Small 3-pin (GP) connector
  • large 6-pin connector (Molex)
  • aluminum heatsink
  • Potentiometer of 20K if you want to add volume control

 

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