As a special equipment, the existence of mobile phone jammer has certain advantages and disadvantages. The following will be a brief analysis from a technical point of view.

Benefits:
1. Security:
In some specific occasions, such as prisons and military facilities. Cell phone signals may become a channel for illegal information transmission, posing a threat to security. Cell phone jammer can effectively block cell phone signals in these occasions. Prevent illegal information transmission, thus maintaining security.

2. Fair examination:
During the exam, the mobile phone may become a cheating tool, which will affect the fairness of the exam. The mobile phone jammer can block the mobile phone signal in the examination room. Prevent candidates from cheating by using mobile phones, thus maintaining the fairness of the exam.

3. Interference management:
In some special circumstances, such as hospital operating rooms, aircraft take-off and landing, etc., mobile phone signals may interfere with the operation of equipment. The mobile phone jammer can block the mobile phone signal in these environments to avoid interference to the equipment operation.

Disadvantages:
1. Communication interruption:
Cell phone jammer will block the cell phone signal, resulting in communication interruption. In emergencies, such as fires and natural disasters, mobile phones may be an important tool for people to contact the outside world. The use of mobile phone jammers may cause people to fail to get rescue information in time, which will aggravate the crisis.

2. Health risks:
Some studies show that long-term exposure to electromagnetic radiation generated by mobile phone signal jammers may have a negative impact on human health. Although the current evidence is not sufficient, it is still a problem worthy of attention.

3. Legal and moral issues:
In many countries and regions, it is illegal to use mobile phone jammers. This kind of behavior may lead to legal responsibility and moral condemnation, and cause damage to social order.

To sum up, mobile phone jammer has certain application value in certain occasions, but it also has obvious disadvantages. When using mobile phone jammer, we should weigh the advantages and disadvantages to ensure that its use conforms to laws, regulations and ethics, and at the same time minimize the damage to public interests.