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Hi-Fi power amplifier circuit and power supply circuit

Hi-Fi power amplifier circuit and power supply circuit

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As indicated in the chart (from 20W to 80W RMS).

Some explanations:

- The first thing you have to do is test the amplification factor hfe or β of the last power tube. If their difference is greater than 30%, the amplifier will not give you a clear sound. I am using MJ3001 and MJ2501 transistors, their The difference is 5%.

- Before turning on the power, you must short-circuit the input, string an ammeter at the output of the amplifier, then turn on the power, adjust R13 to make the ammeter current to microampere level, if you are lucky enough, you can reach 0, the ammeter current is 10 Microamperes are easy to do.

Power amplifier circuit diagram:

Hi-Fi power amplifier circuit and power supply circuit

Power circuit:

Component and attribute table:


20 / 35 W

25 / 40 W

35 / 60 W

50 / 80 W

80 / 125 W

T1

BC546

T2

BC556

T3 (PNP Darlington)

BD898, BD678

BD896, BD676

BDX34

MJ900G

2N6052, MJ2501

T4 (NPN Darlington)

BD897, BD677

BD895, BD675

BDX33

MJ1000G

2N6059, MJ3001

C1

10 to 12 pF

C2

4.7 to 5.6 nF

C3 (no polarity capacitor)

1 to 10 uF

C4, C5

2200 uF / 35 V

4700 uF / 35 V

4700 uF / 35 V

4700 uF / 50 V

4700 uF / 50 V

R1, R2, R9, R12

10 kΩ

R3, R4, R5, R6, R14, R15

3.3 kΩ

R7, R8

680 Ω

R10

100 kΩ

R11

47 kΩ

R13 (fine tuning resistor)

10 kΩ

F1 (fast)

1,2 A

1,6 A

2 A

2,2 A

4 A

BR1

B40C1500

B40C2000

B40C2800

B40C3200

B40C5000

Cooler

4,5

2,7

2,0

1,7

1,5

Transformer secondary voltage (± 20 %)

20 + 20 V

20 + 20 V

20 + 20 V

22 + 22 V

22 + 22 V

Transformer secondary current

0,8 A

1,2 A

1,3 A

1,5 A

2,5 A

Power (RMS)

20 W

25 W

35 W

50 W

80 W

Music power

35 W

40 W

60 W

80 W

125 W

Minimum speaker impedance

8 Ω

8 Ω

8 Ω

8 Ω

4 Ω

Supply voltage (± 20 %)

± 25 V

± 25 V

± 25 V

± 30 V

± 30 V

Maximum current

0,54 A

0,85 A

1,0 A

1,15 A

2,0 A

Input voltage required for maximum power

1,8 V

1,5 V

1,7 V

1,95 V

1,7 V

input resistance

10 kΩ

Bandwidth (-3 dB)

0 – 100.000 Hz

THD at 1⁄2 P

0,04 %

THD at Psin

Max 0,18 %

Frequency response

93 dB

Door Lock Motor Characteristics 1. No direction: don't need to distinguish the door direction, left and right sides, both inside and outside the door, can be universal. (convenient purchase locks and reduce inventory). 

Door Lock Motor  Dc Gear Motor

2. Power: the power consumption is only equivalent to one 5 of the electric control lock, electric lock, 3 A magnetic lock power to open the door, often consumes 0.27 A. And spiritual lock unlock instantaneous current is less than 0.5 A, reduced the entrance guard, talkback host power consumption.

3. No collision: close the door without collision, reduces the choice of door closers requirements (not necessarily with 65 kg of door closers, door closers are free to choose to suit the door), to solve the building door because the door closers clash of the hydrodynamic force is too high, it is not easy to make the door more deformation, prolong the service life of the body. 

4. The voice is light: close the door automatically locked, no noise, solves the noise due to electric control lock itself. 

5. Life is long, life is up to 350000 times


Operating temperature range:

Mini Door Lock Motor should be used at a temperature of -10~60℃.

The figures stated in the catalog specifications are based on use at  ordinary room temperature catalog specifications re based on use at ordinary room temperature  (approximately20~25℃.

If a  Lock Motor  is used outside the prescribed temperature range,the grease on the gearhead area will become unable to function normally and the motor will become unable to start.Depending on the temperature conditions ,it may be possible to deal with them by changing the grease of the motor's parts.Please feel free to consult with us about this.


Storage temperature range:

 lock motor  should be stored ta a temperature of -15~65℃.

In case of storage outside this range,the grease on the gearhead area will become unable to function normally and the motor will become unable to start.


Service life:

The longevity of  Door Lock Motor is greatly affected by the load conditions , the mode of operation,the environment of use ,etc.Therefore,it is necessary to check the conditions under which the product will actually be used .The following conditions will have a negative effect on longevity.Please consult with us should any of them apply.



●Use with a load that exceeds the rated torque

●Frequent starting

●Momentary reversals of turning direction

●Impact loads

●Long-term continuous operation

●Forced turning using the output shaft

●Use in which the permitted overhang load or the permitted thrust load is exceeded

●A pulse drive ,e.g.,a short break,counter electromotive force,PWM control

●Use of a voltage that is nonstandard as regards the rated voltage

●Use outside the prescribed temperature or relative-humidity range,or in a special environment.

●Please consult with us about these or any other conditions of use that may apply,so that we can be sure that you select the most appropriate model.


when it come to volume production,we're a major player as well .each month,we rurn out  600000 units,all of which are compliant with the rohs directive.Have any questions or special needed, please contact us, we have the engineer group and best sales department to service to you

Looking forward to your inquiry. Welcome to our factory.

Lock motor


Door Lock Motor

Door Lock Motor,Mini Door Lock Motor,Door Lock Dc Motor,Door Lock Gear Motor

Shenzhen Shunchang Motor Co., LTD. , http://www.scgearmotor.com