AB Push-pull power amplifier made by 6C19 electronic pipe, 6C19 Power Amplifier
Keywords: 6C19 electronic pipe power amplifier circuit
Author: Wang Ding
First, the circuit features use 6N11 to do voltage amplification and P-K split phase, 6N6.
6C19 power output, circuit is shown below. The 6C19 power tube uses a self-sufficient pressure, and the quiescent current is about 55 mA, and the cathode voltage can be adjusted by adjusting the resistance of R13, thereby adjusting its bias value and operating point. R13 can be used in parallel with multiple resistors. The number of total watts is better.
It is generally believed that the P-K splitting inverted circuit does not need to be adjusted. The same resistance is the same as the screen of the tube and the cathode detector value, as they are series relationships. The series circuit current is equal.
The two sets of voltages are opposite to the phase amplitude. In fact, in fact, in the splitting inverting circuit, since the load is an output transformer. Not a pure resistance, its impedance is the frequency change.
The difference between output impedance results in different frequencies, the signal voltage of the cathode output is always higher than the signal voltage of the screen output, which is the characteristics of the P-K splitting inverted circuit. It is also its weakness. Therefore, the value of the screen resistor R4 should be larger than the value of the cathode resistor R5, and the resistance should be determined in the adjustment. The specific method is to enter a 3 kHz-5 kHz sine wave signal at the input. The two output voltage is measured, and the output voltage is substantially equal by adjusting the resistance of R4 and R5.
Second, the output transformer 6C19 is low, and the output transformer is relatively simple. With a sheet thickness of 0.35 mm, the tongue is 32mm. The EI-type high silicon core of 45 mm is stacked. The primary use φ0.27mm enameled wire around 1100 +1100 (800fz), the secondary with φ0.80mm enameled wire 105 (8Ω). At the beginning, the secondary used 3 clamps 2 structure, the primary 1100 +1100. The secondary 35 匝 +35 +35, the primary clamp is between the secondary, the silicon steel sheet is cross-inserted, see the picture.
Third, the power transformer power transformer has a lower cost, and the thickness of 0.5 mm is removed by the core. The tongue is 40mm, the stack is 60mm, and the primary 220V is 350 φ0.80mm. The secondary high pressure 180V has a φ0.5mm enameled wire with a φ1.62 mm enamel wire windings with φ1.62 mm enamel wire. The 6C19 filament windings are released around 16 turns with φ1.50mm. The electrostatic shield is made of thickness of 0.2 mm copper skin between the initial level. Fourth, the rectifier filter circuit is rectified by Motorola fast recovery diode.
Model MR751, invert pressure 600V. Current 6a. The blocking ring is a large current type of 0.5H 500mA. Because the rectifier filter circuit is also a signal channel. The frequency of the whole machine is extended to the frequency of the whole machine at a thin film capacitance of each large electrolytic capacitor.
5. The connection line should be good in the machine. The high purity copper wire is connected between the components, especially the signal line, can not be hidden. Be sure to use the quality of high temperature-plated silver shield line. The welding level one is that the grounding wire and the filament line are close to the bottom plate, and the wells all the components that need to be grounded are finished. The second is a coupling capacitor at all levels of hanging welding. Finally, the high-temperature plastic sleeve is highly resistant to high temperature plastic sleeves with φ0.8mm enameled lines, and the B + high pressure power line is connected. Such hierarchical wiring can minimize parasitic coupling. Improve signal to noise ratio.
Sixth, cooker and commissioning generally, the new machine is unmistadless as long as the line connection is accurate. Extuncture can be energized. In this situation. As long as the voltage at + 100K, the voltage is in the range. Not too fine first. The machine will be debugged in accordance with the foregoing steps and points. After the debug is completed, the resistance of the negative feedback resistor R14, R14 is determined by the listening effect.
Seven, the sound effect is a month after a month. The performance is basically stable, and since it is satisfactory to use the car to a friend. With his 300B pair. Speaker is a pair of 8-inch triple-frequency sensitivity 90dB floor fell, Sony CD machine. Since playing people, strings and symphony. The sound effect is more than 300b, the bass is powerful, the boxing is in the heart, the tall is bright and noise, it is crisp and sweet, the sound is naturally supple, the analytical force is quite high. When playing large dynamic symphony, its dynamic and even more than 300B. The 6C19 strong current output capability is the satisfactory foundation of this machine.
Our other product:
