Calrad 40-979 Digital Cable Hum Eliminator

Calrads new 40-979 Inductor based ground hum eliminator provides a high impedance barrier to AC power related ground currents, preventing hum or buzz in low level audio sound or hum bars in video systems, while providing a bi-directional path for 2 way digital set top boxes and cable modem signals. Works with all Analog, Digital, High Definition, Internet Modem systems.

Specs.

Meets FCC Part 76 Regulations for CATV systems 
Bandwidth 1.6Ghz, Low VSWR
Input-Output Impedance 75 ohms

What causes hum and ground loops?
Hum and ground loops are typically generated two ways 1) differences in voltage between equipment grounding points and 2) magnetic coupling. A long cable run may suffer from both problems, video equipment is not usually connected to the same ground terminal in different parts of a building and the cable may be run next to other wires and cable.  

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