Commonly used anti-noise components include vehicle-mounted capacitor or coaxial vehicle-mounted capacitor (especially effective for perfunctory high-frequency noise), current coil (inductor), LC filter, grounding wire, diode and so on.
1, resist the noise of incineration system.
Check whether the capacitor between the anode of the incineration coil and the ground is installed. If equipment is installed, check whether the capacity is reduced. If the platinum contact is simply ablated and the spark is disturbed, it is necessary to replace the nonpolar capacitor with a capacity of 5UF /400V V.
Check whether the burning high-voltage line uses carbon wire. If only metal wires are used to interfere, the radio reception is somewhat interfered and must be replaced.
Spark noise can be suppressed by increasing damping resistance. The method is to connect 1 megohm resistor in series on the high-voltage line output from the incineration coil to reduce interference.
2, motor noise cleaning
First of all, audio equipment and signal lines are far away from motors and motor wires. 1 nonpolar capacitors can be connected in parallel at both ends of the motor, or two inductors can be connected in series in the positive and negative wires of the motor, and then the two nonpolar capacitors are connected in the positive and negative wires of the motor respectively, and the other end is grounded to form a filter circuit, which is used to absorb the spark of the motor carbon brush and reduce the noise.
3. For the noise generated by the relay-free electric horn, there are mainly the following cleaning methods:
The terminal of a horn is grounded and connected with a capacitor.
An inductor is connected in series at the terminal of a horn, and then a capacitor is connected in parallel to ground.
Application method of separation on two loudspeaker terminals-.
Connect a capacitor in parallel between the horn button contacts of the steering wheel.
4, the noise of the electric horn with relay, cleaning methods mainly include the following:
The electric horn bracket should be in contact with the body.
Connect a capacitor in parallel at both ends of the relay contact, or connect a capacitor in parallel at both ends of the contact respectively.
5. Poor grounding will produce noise.
If the hood is not firmly grounded, all the hoods will become an antenna, radiating the noise from all parts of the car to the surrounding space, and introducing the sound system from the antenna and various circuits. When installing the connecting wire between the hood and the car body, the paint, oil stain and dirt at the connection must be thoroughly removed.
The engine (engine) should be connected to the car body, or between the front wheel suspension and the car body, and between the exhaust pipe and the car body.
6. Power cord noise:
In order to effectively eliminate the noise generated by the power line, the current loop should be placed close to the power amplifier device. If there are multiple power amplifiers, a current loop should be installed near each power amplifier. Because noise can be transmitted from one power amplifier to another, a single current loop will fail.
7, signal line (RCA) incoming noise:
The signal line should be far away from the power line and separated from the power lines on both sides of the car body to prevent the possibility of interference. If the signal wire has a double-layer shielding net, the outer shielding net should be connected to the bushing.
Extended data:
Ways to intrude into car audio noise;
1, invade the power line (enter the system through the host and power amplifier power line).
2. Current through ground wire (through antenna ground wire and power amplifier ground wire).
3. Being induced by other wires and harnesses (received by antenna and induced by original vehicle harness).
4. Electrical interference (electric horn, motor, etc.). ).
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