Sep 23rd, 2009
by Electronics Online.
This simple amplifier circuit will be nice for newbie project/junior student. Require an IC LM386N to build a mono channel amplifier. There are few components such as capacitor, resistor, potensiometer and speaker in this circuit, so the students will know the real shape of components.
Parts List :
Capacitors :
C1, C5 2.2 uF / 50Vecap _________2
C2, C9 10 uF / 25V ecap _________2
C3, C7 100 nF mono (104) ________2
C4 100 uF / 16V ecap ____________1
C6, C8 470 uF / 16V ecap ________2
C10, C11 47 nF mylar (473) ______2
Resistors :
R1, R2 10 ohm ___________________2
Pot 1 10k ohm stereo pot ________1
Misc. :
IC 1, 2 LM386N __________________2
8 pin IC socket _________________2
Jun 19th, 2009
by Electronics Online.
Here the simple and unexpensive 100W power audio amplifier. This circuit should be easy to made.. 
Use this power supply circuit:
Mar 31st, 2009
by Electronics Online.
This amplifier circuit design is based on the 18 Watt Audio Amplifier, and was developed mainly to satisfy the requests of correspondents unable to locate the TLE2141C chip. It uses the widespread NE5532 Dual IC but, obviously, its power output will be comprised in the 9.5 – 11.5W range, as the supply rails cannot exceed ±18V.
As amplifiers of this kind are frequently used to drive small loudspeaker cabinets, the bass frequency range is rather sacrificed. Therefore a bass-boost control was inserted in the feedback loop of the amplifier, in order to overcome this problem without quality losses. The bass lift curve can reach a maximum of +16.4dB @ 50Hz. In any case, even when the bass control is rotated fully counterclockwise, the amplifier frequency response shows a gentle raising curve: +0.8dB @ 400Hz, +4.7dB @ 100Hz and +6dB @ 50Hz (referred to 1KHz).
Mar 10th, 2009
by Electronics Online.
Here the schematic diagram of 60 watts power audio amplifier. The main components is a pair of power transistor 2N3055.
Further information, please visit this page
Feb 11th, 2009
by Electronics Online.
Circuit Description:
This amplifier uses a dual 20 Volt power supply and delivers 15 watts RMS into an 8 ohm load. Q1 operates in common emitter, the input signal being passed to the bias chain consisting of Q8, Q9, D6, D13 and D14. Q8 and Q9 provide a constant current through the bias chain to minimize distortion, the output stage formed by a discrete darlington pair (Q2,Q4) and (Q7,Q11). The last two transistors are power transitors, specifically the 2N3055 and MJ2955. The 7.02K resistor, R16 was made using a series combination of a 4.7K, 680 Ohms, and two 820 Ohms. The 1.1K resistor, R3 was made using a 100 Ohms and a 1K resistor. You can use this circuit with any walkman or CD player since it is designed to take a standard 500mv RMS signal.
