North Korea developed its GPS blocker capability in response to GPS-guided weapons

The country maintains a regiment-sized GPS signal jammer unit near the capital of Pyongyang and battalion-sized units near the demilitarized zone. Jamming in 2012 was traced to the town of Kaesong, just over the border.

North Korea reportedly purchased truck-mounted GPS cellphone jammers from Russia with a range of thirty to sixty miles, and in 2011 was reportedly at work on even longer-range jammers. Sixty miles is more than enough to jam the greater Seoul metropolitan area, home to half of South Korea's population.

South Korean civil aviation is particularly vulnerable to jamming because Incheon International Airport—which serves the greater Seoul metropolitan area—is close to the border with North Korea. Incheon is only 23 miles from the demilitarized zone. 49.2 million passengers passed through Incheon in 2015, making it one of the busiest airports in the world.

This device sends high amplitudes of emp to destroy nearby devices, be sure to have fun using this, but be careful this high power jammers involves thousands of volts which can lead to heart attack or death even.

The problem is that many potential adversaries drone radio frequency jamming

Such as the Chinese and the Russians, have developed advanced digital radio frequency memory (DRFM) jammers. These jammers, which effectively memorize an incoming radar signal and repeat it back to the sender, seriously hamper the performance of friendly radars.

Worse, these new jammers essentially blind the small radars found onboard air-to-air missiles like the Raytheon AIM-120 AMRAAM, which is the primary long-range weapon for all U.S. and most allied fighter planes.

ight now, the Defense Department—led by the Navy—is working to increase the range of the AIM-9X version of the Sidewinder by 60 percent to give the Pentagon’s fighter fleet some sort of counter to the jamming problem. 

This official added that future weapons would be far better at countering enemy jamming—so much so that future fighters will not need to have the sheer speed and maneuverability of an aircraft like the Raptor. “I think top end speed, super cruise, and acceleration will all decline in importance as weapons advance in range and speed,” he said.