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Cable Picture Degradation When Using an APC Coaxial Surge Protector

Issue:

After connecting an APC device with Coax Protection, customer observes picture degradation or loss of digital channels.

Product Line:

SurgeArrest, Protectnet, Back-UPS, Back-UPS Pro, APC AV line of products

Environment:

Standard dB available to a home is 14 dB. Most television tuners require 7 dB

to get a picture. Therefore, if one has a VCR and TV with coax cable between

them, then 7 dB is all that is left for both. If one also has a FM receiver

connected which requires 4 dB, the chances of 'ghosting' or lines being present

are higher. Several cable subscribers have opted to split their cable

connection so they can have a TV in the living room and the bedroom for

example. Cable deregulation allowed customers to do this, but the cable

company will not boost the signal to compensate unless they are informed by to

do so. The customer would be billed for the boosted signal. The end result is

a serious degradation of the signal. Inserting a cable protector like an APC

Per3C, Per7C, or Pro8TV would cause a slight, additional dB loss. The signal

has now degraded to the point where any magnetic interference could propagate

into the cable signal."


Cause / Resolution:

APC Coax protection has been tested from 30 MHz to 1 GHz.
It's insertion loss is at 1 GHz were attenuation is 5 dB.
Over most of this frequency range, the insertion loss is ~ 1 dB

1. Check all cable ""F"" Connectors for proper crimping. Buy pre-cut and

terminated cables from an electronics store; such as Radio Shack.



2. Use a 50 ohm terminator for any exposed non-connected female connectors

(available at many electronics stores).



3. Purchase a cable signal booster (boosts cable signal to around 20-24 dB).



4. Inform their local cable provider that they are splitting and pay for an

extra connection. A cable company can boost a signal. It is a cleaner way to

go rather than using a booster.




 
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