＜100$

The effective range of a jammer is affected by several factors, including:

1. Frequency: The signal propagation characteristics of different frequency bands are different. Generally, lower frequency signals (such as 2.4 GHz) are better than high frequency signals (such as 5 GHz) in terms of distance and obstacle penetration capabilities.

2. Output power: The higher the transmit power of the jammer, the greater the coverage area.

3. Environmental obstructions: Walls, furniture, and other objects can absorb or reflect wireless signals, affecting shielding effectiveness. Metal objects in particular significantly reduce signal propagation.

4. Antenna design: The type and layout of a jammer's antenna affects its radiation pattern and coverage. Directional antennas can focus the signal to a specific area, while omnidirectional antennas provide 360-degree coverage.

5. Weather conditions: Rain, snow and other meteorological conditions may have an impact on signal propagation, especially in outdoor environments.

6. Interference sources: Other wireless signal sources in the surrounding environment (such as other Wi-Fi networks, Bluetooth devices, etc.) may cause signal interference and affect the effectiveness of the jammer.

7. Distance: The distance from the shield directly affects its effect. Usually, the farther the distance, the weaker the shielding effect.

Based on these factors, the actual effective range of the jammer may vary greatly.