What to do if the spectrum analyzer has a black screen and won’t turn on? - Shared by Agitek spectrum analyzer maintenance engineer

Spectrum analyzers are widely used in the RF field. They are also known as "RF multimeters". In addition, a high-frequency spectrum analyzer is not cheap. A mid-range or high-end instrument may cost as much as a car. Therefore, when a spectrum analyzer fails, most people choose to repair it. Antai Testing and Repair Center summarizes the six common failures:

1. Power failure: Cannot boot normally

2. Input fault: abnormal impedance; no signal; abnormal signal amplitude

3. Test and analysis failure: frequency and phase test abnormalities

4. Display failure: flower screen; black screen

5. Button failure: the button does not respond; the adjustment knob does not respond

6. Interface failure: storage medium is not recognized; cannot connect to the control system

7. Other usage issues, etc.

Today, based on many years of maintenance experience, Antai Spectrum Analyzer Repair Center would like to share with you how to judge and deal with the common faults - black screen and no boot phenomenon:

A spectrum analyzer is similar to an oscilloscope. It has an independent power module inside to power the mainboard and various functional modules, so it is necessary to pay special attention to power safety.

Generally speaking, the cause of the black screen is the power failure, so first determine whether the power supply is normal. Spectrum analyzers generally use switching power supplies, which can be eliminated and repaired using the general maintenance methods of switching power supplies. If there is no problem with the power supply, another common cause is a high-voltage circuit failure. Here we will focus on the LCD screen of the spectrum analyzer. The light emitted by the LCD display is emitted by the internal lamp tube. The characteristics of the lamp tube are similar to those of household fluorescent lamps, but it requires a high voltage of 400 to 800V for normal operation. If the lamp tube does not light up, first use a high internal resistance multimeter to test whether the high voltage is faulty. If the high voltage is normal, replace the lamp tube; otherwise, it is a high-voltage inverter circuit failure.

30% of spectrum analyzer failures are caused by power failures. Here are some precautions for using spectrum analyzers shared by Antai Spectrum Analyzer Repair Center:

1. Use the original power cord of the instrument;

2. Check whether the instrument's AC input has a 110V/220V switch. If so, make sure the switch is in the 220V position;

3. Confirm that the power grid is stable. When a high-power appliance is connected to the power grid, turn off the instrument and unplug the power cord, and then use it after the power grid is stable;

4. When turning on the machine: first plug in the AC power cord, then press the power button to turn on the machine;

When shutting down: first press the power button to shut down, then unplug the AC power cord;

5. Pay attention to the instrument's operating environment and clean the dust regularly.