How to adjust the voltage of the power amplifier and how to measure the voltage of the power amplifi

1. The zero point potential is that the voltage of the two push-pull power tube collectors to the output end should be equal (the error should be within 20mv), if the zero drift is too large, there will be DC passing through the speaker, which will cause static noise.

2. First of all, the input terminal is short-circuited, the voltage is detected and adjusted, the DC current of the multimeter is 100mA connected to the output end, the midpoint is adjusted to make the reading minimized, the 10mA gear is changed to continue to adjust to make the reading minimized, and the fixed resistance of the same resistance value is replaced to re-detect. On the contrary, if it is a pure Class A power amplifier, it is normal to be hot without turning on the volume, and it is abnormal if it is not pure Class A.

If it is a pure Class A power amplifier, it is normal to be hot without turning on the volume.

If it is not pure class A, it is abnormal, the zero point potential is that the voltage of the output end of the collector of the two push-pull power tubes should be equal (the error should be within 20mv), if the zero drift is too large, there will be DC in the horn, and even burn the expensive horn! This must not be taken lightly!

Steps to adjust the zero potential of the power amplifier: first, the input terminal is short-circuited--- the voltage is adjusted--- the DC current of the multimeter is serial into the output terminal--- the midpoint is adjusted to make the reading smaller--- and the reading is changed to the 10mA gear, and the reading is continued to be adjusted - change to a fixed resistance of the same resistance value to re-detect --- repeatedly.

If it is an OCL power amplifier, the midpoint voltage is the voltage of the horn output to the ground, and the OTL power amplifier is in front of the large capacitance of the horn output. When it comes to measuring quiescent current, you can directly connect the ammeter into the positive end of the power supply and measure the volume to the minimum. If it is more accurate, the table will be connected to the C pole of the power amplifier ungraded current amplification triode, if it is multi-tube parallel, that is, only one tube is connected, and then multiply the multiple of how many groups of parallel connections after measurement.

Extended information: According to the number of first training of the amplifier output stage amplification element, it can be divided into single-ended amplifier and push-pull amplifier. The output stage of a single-ended amplifier is amplified by one amplifier element (or elements but in parallel in a group) to amplify the signal plus or minus two and a half cycles.

Single-ended amplification machines can only be in Class A working condition.

The voltage between the two terminals connected to the horn, that is, the output and the ground wire (GND).

If it is an OCL power amplifier, the midpoint voltage is the voltage of the horn output to the ground, and the OTL power amplifier is in front of the large capacitor of the horn output. To measure the quiescent current, you can directly apply the ammeter.

Insert the positive end of the power supply and measure the volume to the minimum.

If it is more accurate, the meter is stringed into the power amplifier ungraded current amplification stage triode.

C pole, if it is a multi-tube parallel, that is, only one tube is connected, and then multiply by the multiple of how many groups of parallel connections after being measured.

The black pen is grounded, and the red pen is connected to the output terminal to know the midpoint voltage! Wish.

Summary. Hello, how to adjust the voltage of the power amplifier to ov:1, first short circuit the input terminal, and detect the adjustment voltage.

2. Serial the DC current of the multimeter 100mA into the output terminal, and adjust the midpoint to minimize the reading.

3. Switch into the 10mA gear and continue to adjust to minimize the reading, and replace it with a fixed resistance with the same resistance value to re-detect.

The function of the power amplifier is to amplify the weak signal from the sound source or preamplifier and push the speaker to play sound. A good sound system amplifier plays a big role. Power amplifier is the largest family of all kinds of audio equipment, and its function is mainly to amplify the weaker signal input from the audio source equipment, and generate a large enough current to push the speaker to play back the sound.

Due to the consideration of power, impedance, distortion, dynamics, as well as different ranges of use and control adjustment functions, different amplifiers have different internal signal processing, circuit design, and production processes.

In addition to the amplification signal of the ordinary power amplifier to drive the function of loudspeaker sound reinforcement, the frequency-shift power amplifier can also effectively suppress the on-site howling, ensure the transmission quality of voice, even in the case of poor environment, it can also greatly suppress the whistle and protect the audio equipment from burning out due to the whistle. Frequency-shift amplifiers are widely used in high-end multi-electric classrooms, training rooms, small conference rooms or other simple sound reinforcement occasions, microphones can be directly connected to the frequency-shift amplifier, and can effectively suppress the howling noise generated by the microphone to the speaker, and support background access for sound reinforcement.

How to adjust the voltage at the midpoint of the amplifier to OV

Hello, how to adjust the voltage of the power amplifier to ov:1, first short circuit the input terminal, and detect the adjustment voltage.

2. Serial the DC current of the multimeter 100mA into the output terminal, and adjust the midpoint to minimize the reading.

3. Switch into the 10mA gear and continue to adjust to minimize the reading, and replace it with a fixed resistance with the same resistance value to re-detect.

The function of the power amplifier is to amplify the weak signal from the sound source or preamplifier and push the speaker to play sound. A good sound system amplifier is indispensable. The power amplifier is the largest family of various types of audio equipment carried by the returnee, and its function is mainly to amplify the weaker signal input from the audio source equipment, and generate a large enough current to push the speaker to play back the sound.

Due to the consideration of power, impedance, distortion, dynamics, as well as different use ranges and control adjustment functions, different power amplifiers have different internal signal processing, circuit design and production processes.

In addition to the amplification signal of the ordinary power amplifier to drive the function of loudspeaker sound reinforcement, the frequency-shift power amplifier can also effectively suppress the on-site howling, ensure the transmission quality of voice, even in the case of poor environment, it can also greatly suppress the whistle and protect the audio equipment from burning out due to the whistle. The microphone can be directly connected to the frequency-shifting power amplifier, and can also effectively suppress the whine generated by the microphone to the speaker, and support the envy of the background access for sound reinforcement.

At that location, adjust the midpoint voltage.

Click on Voltage in the bottom left corner.

The midpoint voltage of the power amplifier is adjusted at the factory, and the midpoint voltage is 0V, which generally cannot exceed 200mV. If you are an enthusiast and understand circuits, adjusting the emitter current of the amplifier tube to a certain level can effectively eliminate the crossover distortion.

The following is the best current of the power amplifier tube extracted from foreign books, according to the size of the emitter resistance, adjusted according to the value of the figure below, the power amplifier sound will be a grade, and my power amplifier is adjusted according to this value.

But if you're not very proficient in circuitry, it's best not to adjust it, because it's easy to burn out the amplifier tube.

At the other end of the emitter resistor of the final amplifier tube, for the OTL circuit, it is the end that is connected to the horn (the other end of the horn is connected to the "ground"); For OCL circuits, the output capacitor is connected to one end of the circuit board (the other end of the output capacitor is connected to the horn).

First find the emitter of the final amplifier tube, and then find the emitter resistor, one end of the emitter resistor is connected to the emitter, and the other end is the midpoint voltage.

This is shown in red in the figure below.