50W Power Amplifier circuit based on STK-1050

Here is one of the circuit diagram of a power amplifier with the STK1050 single power chip which is supported by several components that make a better sound output. This amplifier is a single output amplifier, so if you want a stereo amplifier, then you must make a similar circuit.

50W Power Amplifier with STK-1050 circuit diagram

STK-1050 Features:
STK1050 has some features that make it superior and good for your audio amplifier.

  1. Does not require externally connected emitter resistors.
  2. Values of emitter resistors have carefully been reviewed to provide superior characteristics.
  • Better supply voltage utilization permits designing power supply voltage that are about 0.7V (for RL=4ohms) lower than those required for previous DPP models.
  • Maximum allowable power consumption for each resistor is 5W or higher, permitting accomodation for all loads.
  • Peak allowable current is 18A or more, providing an ample margin even for peak currents under when short circuited or similar emergencies.
  • In particular, maximum output 4 ohms have been enormously improved.

  1. Use of emitter resistors facilitates meeting different safety standards and designing PCBs
  2. Mutual interferences in the high-frequency range caused by layout of externally connected emitter resistors no longer exist. This facilitates lower distortion factors.
  3. Pins are used for emitter resistor output terminals that were not conected in previous DPPs. All other terminals remain uncharged; there is no need for major circuit board changes.

Download STK-1050 datasheet

One Transistor FM Radio

Thi circuit is very simple with only one transistor. No need additional active components, but if you want to hear the sound louder, just build another amplifier circuit... :)

One Transistor FM Receiver circuit diagram

Part designator Part description
C1a,C1b 10 pf, 50 v, ceramic disc capacitor
C2 22 pf, 50 v, ceramic disc capacitor
C3 RF tuning capacitor
C4 330 pf, 50 v, ceramic disc capacitor
C5,C8 0.001 uf, 50 v, ceramic disc capacitor
C6 0.22 uf, 50 v, film capacitor
C7 0.0047 uf, 50 v, ceramic disc capacitor
C9 22 uf, 16 v, electrolytic capacitor
D1 TL431AIZ voltage control Zener (shunt regulator)
EPH1 High impedance earphone
L2 22 uh RF choke
Q1 2N4416A JFET transistor
R1 470K, 1/4 w, resistor
R2, R3 1K, 1/4 w, resistor
R4 10K, 1/4 w, resistor
R5 1M, 1/4 w, resistor
R6 100 ohm, 1/4 w, resistor
S1 Small SPST switch
screws for C3 screws for mounting C3 (2 needed)
nylon screw #4 nylon screw used for tuning C3
battery connector mini battery snap

More instruction how to build this circuit, visit this page