VU level audio meter driver board + 2 VU meters

product features:
1. Using professional audio VU driver IC, not the TA7318 we used before, this IC contains square root dynamic compression circuit, logarithmic output characteristics, to avoid the small signal pointer does not move, when the signal is large, the pointer hits the bottom The phenomenon.
2. The IC has a mute function. The mute function pin will get a low level at the moment of power-on, which can avoid the phenomenon of the pointer hitting the bottom at the moment of power-on. In order to comply with the boot habit, the pointer will swing with a small swing.
3. The circuit uses 6-12VDC power supply, using original IC BA6138, it will be very convenient to use.
4. The double-sided circuit board is used to ensure the firmness of the crimping terminal, so that the pads of the terminal may not be loose after multiple wiring.
5. Each drive board has been tested and adjusted by our professional test stand to ensure the consistency of quality. The design and layout of the drive board are beautiful and reasonable, and there is no interference and self-excitation. Each board has been tested and adjusted by our professional test stand. There is no special requirement. We input 1W/8 ohm (2.83V), and use the P-55 meter to do the load test. The pointer swing is 0DB scale. If you have special requirements, you can send a text message to explain. In addition to adjusting the load potentiometer, the swing adjustment can also be considered from the input voltage divider circuit.
The brightness of the backlight can be achieved by adjusting the resistance of R9 and R10. With the electrical parameters of the backlight, it can be easily calculated according to Ohm's law. If you want to help, please text us.
6. Crimp terminal
The crimping terminal we choose has a moderate height. The most important thing is that the crimping method is very reasonable, which can firmly compress wires of various sizes. In addition, we use a double-sided board, and the pads of the crimping terminals are relatively firm and not easy to loosen.
7. Circuit board size
The installation size of the circuit board, the outer frame is 67.4MM*56MM, and the installation size of the screw hole: 57MM*50.5MM. M3 screws are suitable for the screws.
introduce:
1. This is a new upgraded version of the dedicated VU meter, warm yellow backlight, backlight voltage 6-12V, AC and DC can be used. Suitable for 5W-60W amplifiers and amplifiers, direct power amplifier output (connected to the speaker in parallel), easy installation, simple adjustment, high sensitivity, etc., with overshoot protection, praised by the majority of DIY netizens. Suitable for 5W-60W power amplifiers and AV amplifiers, mainstream amplifiers 6P6 300B KT88 can be used with confidence, and 3W radios are also supported.
2. The terminal block is improved, and the terminal block welding is more convenient after the improvement. Simple wiring, convenient installation, adjustable pointer jump range, with overshoot protection. The driver board is the latest upgraded version, both AC and DC are available, and the quality is stable and reliable.
Tips:
1. Before use, check whether the pointer is aligned with the zero point. If there is any deviation, use a screwdriver to adjust the pointer to the zero position.
2. The backlight design uses a voltage of 6-12V. When the backlight brightness meets the requirements, reducing the backlight's working voltage can greatly extend the life of the backlight bulb. It is recommended to use 9V.
Precautions:
1. The normal power supply of VU meter and drive board requires 9-12VDC AC and DC power supply cannot exceed 12V. Although it can work for a short time if it exceeds 12VDC, it will burn the protection circuit for a long time. You can use 9v AC power supply. If the background light of the meter head is too dark, the 2W470R resistor on the original version is too large, you can replace it with the included small resistor 2W30R and everything goes smoothly, with the same effect. If the input signal is too strong, connect a resistance of about 10K in series at the input end. If the signal is too strong, the pointer of the meter should be at the bottom. Connect a 10K resistor in series at the input end. If there is no improvement, you can connect two 50W 15K in series at the input end of the power amplifier. Aluminum housing resistor (this is suitable for transistor power amplifier). The luminous effect is more bright and uniform, which is beneficial to prolong the service life. The recommended working voltage can be about 10V.
List:
Driver board X1
VU table X2