The jamming device is intended to identify dozens of enemy radar signals simultaneously, distinguish which are the most threatening and then emit signals to block or confuse enemy air defenses.

Low-level electrical signals can block pain signals from reaching the brain.

Then, an electrical signal blocks erratic impulses that trigger tremors and other symptoms.

No signal to block or intercept.

Special Report: The Technology of Business Bahrain TV station struggles as signal blocked Firms taking on the brandjackers Celebrating hidden heroes of tech Have daily deals had their day?

The jammers are designed to identify dozens of incoming radars, distinguish which are the most threatening to the plane, then emit electronic signals to block or confuse the enemy air defenses that aim deadly antiaircraft missiles.

An opposition satellite station, Lualua TV, operates from London but has found its signals blocked.

If the transition band of the example 200Hz filter is 20 Hz, then the signal should start attenuating at 180 Hz, and finally blocked at 200 Hz.

The distant signals may block local weak signals in some cases.

The approach eventually floundered on the difficulty of redistributing signals within the apartment blocks so prevalent in the Italian urban fabric, and the Net3 team was eventually disbanded in 1997.