What is the welding standard of gun joint (male and female)? ：
1. Peel off the tail (end) of the wound audio cable10mm; ; ?
2. Divide the shielded wire into two strands and carefully rub them, and peel off the tail (end) of the red and white wire1mm.. ?
3. The 1mm head ends of two red and white core wires and two shielded wires are tinned, and the 1, 2 and 3 pins of the tail end of the gun head are tinned; ?
4. One grounding (shielding), two positive electrodes (red), three negative electrodes (white cold), four casings (shielding) and all tin (stripping 1mm). ?
5. After the first four guns are tinned, put the sheath on the thread to be welded. ?
6. When welding, first weld two shields (one grounding and four shells), then weld the negative core wire (white), and finally weld the positive core wire (red). When the tin welding on the gun head is completed, the sheath is sleeved on the wire head to be welded.
Extended data
Microphone characteristics
1, microphone pointing
(1) is generally divided into heart-shaped, super-heart-shaped, figure-8, gun-shaped, omni-directional and so on.
(2) As for these directions, try the microphone. As shown in the figure, the direction indicated by the arrow is in front of the microphone, and the dotted line is the approximate range of pickup, beyond which pickup will be insensitive. If possible, I suggest you try a multi-directional microphone to make you understand the meaning of pointing.
2. Impedance of microphone
Professional recording studio should use low impedance microphone, because it may require a long cable connection, so using low impedance microphone can reduce signal attenuation.
3. Balance line and imbalance line
(1) The balance wire consists of two wires and a shielded wire; The unbalanced line has only one conductor, and the second conductor is replaced by a shielded line. The advantage of a balanced line is that the two wires of the line have equal strength when picking up unwanted noise signals, so they can cancel each other out. The unbalanced line transmits the noise signal to the next stage of the line.
(2) If the audio signal is strong or the unbalanced line is short, noise may not be heard. But the microphone cable is usually very long. Think about it, we pull the cable from the recording studio, pass through the wall of the speaker and then enter the tuning recording system in the control room. Therefore, the balance wire should be used, and the balance plug should be used accordingly: XLR, commonly known as gun head or male and female head; Or TRS with three cores.
Circuit working principle
1, the sound passes through R 1 and C 1 through the microphone; The high-frequency and low-frequency resistance-capacitance filters formed by R2 and C2 are coupled to the base of the transistor. Due to the positive feedback amplification of the transistor, the high-frequency signal of the high-frequency oscillator composed of L 1 and C3 is equivalently fed back to the base of the transistor through C4. The two signals are mixed by triode to form a high frequency FM carrier (88 ~ 108 MHz), which is transmitted to the antenna through C6, and the antenna emits FM signals to the surrounding space.
2. Fine-tuning the gap of L 1 coil can change the frequency value of FM wave. When in use, the receiving frequency of FM can be arbitrarily selected between 88 ~ 108 MHz.
3. Selection of component L 1. Use ∮ 0.6 mm enameled wire to wind ordinary ballpoint pen for four times, use C90 18 high-frequency low-power transistor as triode, and other components can be identified according to the parameters in the drawing.
References:
Baidu encyclopedia-microphone