6N1 gallstone mixed amplifier production, 6N1 amplifier
Keywords: 6n1, cholelithmire mixer
Author: Shandong Cao Chunxiang This machine Theoretical Thought is "The circuit is simple, high efficiency and low consumption". A total of tertiary circuits, the first stage is enlarged by electronic pipe to achieve high-fidelity sound quality; the second stage uses transistor complementary voltage amplifier circuit; third stage current amplification and output circuit. 1 machine (two-channel) shared tube, 10 transistors, dynamic offset, power consumption, power consumption, greatly saved by the AC. It has obtained the sound quality similar to the Amount. The drawings are the schematic (a channel) of the machine.
First, the electron tube voltage amplification promotion level is a good sound quality, the electronic pipe is used in voltage amplification, and the electronic pipe has a very good input, output dynamics, does not generate spike-cut distortion, can be softened to the digital sound source, produce The so-called gallbladder makes the tone round warm.
It also saves the number of voltage amplifiers due to its output voltage, so that the machine circuit has become simple, and the sound quality of the machine is far from the same type of pneumatoider. 6N1 This electronic tube is large, the price is low, and it has been widely used in the 1970s, and it is easy to apply.
Second, transistor voltage amplification of this machine transistor complementary circuit is large, D1, D2 turntable, so that T1, T2 also operates accordingly, each acting, negative half circumference, and offset for current magnification.
Third, the current amplification output stage consists of T3, T4, T5, T6 as the Lincon complementary circuit as the final current amplification output stage, the offset of the machine is dynamic, the current is very small, dynamically biased current with the signal The sharp rise becomes a bias, so the efficiency of the machine is very efficient. The circuit is used to output the collector output. Considering that the number of large-machine amplification is small, the collector output can be obtained to obtain a higher voltage output.
Fourth, the elements are selected from the electron tube to select a low frequency voltage amplifier 6N1 dual triode.
Transistors T1, T2 use A990LC7240, withstand voltage: 100 V; ICM: 0.1A; PCM: 0.4W; T3, T5 A1930 / C5171, withstand voltage: 180V; ICM: 2A; PCM: 20W; T4, T6 A1962 / C5242 , Pressure: 230V; ICM: 15A; PCM: 130W; The above is Toshiba tube, the sound is warm and soft, and the pairing error is less than 5%. The static indicator of this machine is high, which requires a small error of the component itself.
V. Debug 1. Static work point of the tube portion 6N1: ua = 100V; IA = 5mA; -ug = -LV; ra = 20kΩ; power supply voltage + 200V; filament voltage = 6.3V. After the circuit is installed, it can be debugged in static work points according to the above data. After power-on, check whether the anode, gate, and the filament voltage are required. If it does not match, the value of the cathode resistor R3 is finely adjusted; if the gate is about 100 V, the UA is equal to 100 V, and it is quotted several times to meet the requirements. This level is the forefront. Do not do it, it will affect the performance of the whole machine. The resistance power used is large. Try to choose the high quality resistance to reduce thermal noise, the wiring should be reasonable, and the interference source should be avoided.
2. Transistor partial voltage amplification level, this stage is biased by R4, D1, R5, D2, D1, D2 on which D1, D2 should be consistent. R4, R5 is paired, T1, T2 B value should be as best as possible, and the two tube P error is controlled within 3%.
The bias of the current amplification output is provided by R *, D3, R *, D4, two R water resistance to pair, both diodes are also paired. The above D1 to D4 can be switched with a 1 N4148 switch, which cannot be used in a normal rectifier diode, which will affect the frequency response indicator due to the switching speed.
After the transistor is partially installed, the power unit is fixed to the heat sink, which can be electrically tested. First, the input of T1, T2 is grounded, the intermediate point of D1, D2, does not pick up the speaker, to connect the power supply, and observe whether there is abnormal phenomenon, if there is smoke, odor. The power should be turned off immediately, then check and exclude the circuit failure. Normally, the output terminal should be 0V, otherwise any of the C-pole resistors of T1 and T2 should be 0V.
Dynamic debug: Connect the tube portion to the transistor portion. Connect the speaker protection circuit and the volume potentiometer. The volume potentiometer is minimized before booting.
Playing a paragraph of music, delicate sound quality, tone. Return to change C3, C5 audition until satisfaction, then change the negative feedback resistance to change the resistance, listen to the overall frequency, and then adjust it after satisfaction.
This level output does not act 2x50W.
The power supply section, and the speaker protection circuit can refer to the relevant information, the reader is designed, but the speaker protection circuit delay time should be. 1882.60 seconds to accommodate the preheating time of the tube.
Our other product:
