Why should the WiFi transmitter be turned off for 10 seconds before restarting?

In the instructions on repairing, debugging or updating new firmware for devices such as wireless routers and modems, we often encounter one step: Unplug the power, wait 10 seconds and plug in the power cord again.

According to Lifehacker technology page, the core of the problem lies in the capacitors in the device. Basically, these capacitors are like energy bags, loaded when there is current flowing and discharging for the rest of the time. The 10-second power outage of the device is enough to cause most types of capacitors to drain their stored energy and deliver electronic components that provide energy to a completely resting state.

If you've ever opened the PC case, you've probably noticed that a small LED on the mainboard usually takes a few seconds to turn off even after you've unplugged it. Or people who often have to use a PC component removal machine are no stranger to using the power button to quickly discharge after unplugging the power, avoiding electric shock when removing.

Depending on the type of device and the type of capacitor on it, the natural discharge time may vary, but on home network devices, the time of 10 seconds is usually more than enough.

For more severe cases, especially with DD-WRT-up routers, many places recommend users to use the 30/30/30 hard reset method of about 8 steps:

1. Remove the signal wires.

2. Hold the reset button 30s.

3. Still holding the reset button, unplug the power cord.

4. Continue to keep reset 30s.

5. Reconnect the power cord.

6. Continue to keep reset for 30 seconds.

7. Release the reset button and start 10 seconds off.

8. Unplug the power cord and continue waiting 10 seconds before plugging in again.

Now everything will return to the factory default state (it is recommended that some sources indicate that this method causes an error for the WRT54GS, WRT320N and Asus RT-N16).