Jensen Transformers ISO-MAX VRD-1FF Cable TV Ground Isolator

牌子:  Jensen Transformers
價錢: $450

This is a brand new Jensen Transformers ISO-MAX VRD-1FF Cable TV Ground Isolator.

This capacitive based isolator provides a high impedance barrier to AC power related ground currents, preventing hum or buzz in sound systems or hum bars in video systems, while providing a transparent path for radio frequency video and cable modem signals.
Improves audio/video quality by reducing 60 Hz ground currents

2 MHz to 1300 MHz bandwidth spans VHF/FM/UHF/CATV spectrum

Low VSWR helps prevent digital cable channel degradation

Capacitive based design minimizes broadcast channel interference

Meets FCC Part 76 Regulations for CATV systems

The VRD-1FF is made in the USA, is backed by the manufacturer's comprehensive one year warranty, and has a remarkable 20 year warranty on the transformer device itself.  MSRP is USD59.95.

Ground Loops?
(or why the best planned systems sometimes look and sound bad)
It is a subject that is seldom discussed in manufacturers publications, or even in magazines of the trade, but ground loops can happen even in the most carefully planned A/V system.  When ground loops happen in a video system, the result is unwanted hum or video hum bars.  

In cable TV systems, the power supply for the cable system amplifiers are powered by a different source than the equipment that is used to enjoy the programming.  The National Electrical Code requires the cable system to be bonded to the power service entrance ground, but in actual practice, this is not always the case.  Even when the code is properly observed, there are other factors that can cause a difference in ground potential.  It can be because one of the circuits is loaded more heavily than the other, or because one run is longer than the other, or any number of other reasons that are beyond the scope of this article.

The result of this difference in ground potential is commonly referred to as a ground loop.

The Solution
The Jensen Transformers VRD-1FF is elegant in its simplicity.  Just insert it anywhere in the RF line between the cable TV jack and your equipment.

Immediately, the effects of the ground loop become a non-issue.  Problem solved.  There are not too many things that one can install in an A/V system that can provide so much improvement with so little effort.

It is used to reduce/remove hum sound caused by CATV ground loop problem

New from USA, bought 2 pcs, one for own use and one for sell.