Re: Detecting where a coax cable goes to

["BruceR" <br@xxxxxxxxxxxxxxxx>]

Not a guess. Both reasons are correct. I don't make this stuff up. From
the AW catalog:

     F Terminator - 75 ohm terminator properly closes unused coaxial
cable ports on splitters, diplexers, etc. preventing signal leakage and
ingress problems.



From:Charlie Bress
cbress@xxxxxxxxxxx

> Good guess.
> Wrong reason. The unterminated piece of cable, either open  or
> shorted, creates a phenomenon called a standing wave. Depending on
> the length of the offending cable and whether it is opened or
> shorted, the wave can raise the dickens with the right signals.
> Terminating the cable in the correct impedance doesn't let the
> standing wave be created.
>
> Take a look at
> http://www.glenbrook.k12.il.us/GBSSCI/PHYS/Class/waves/u10l4b.html
> It talks  about standing waves in a string, but the concept is
> similar for liquids and radio waves.
>
> Charlie
>
> "BruceR" <br@xxxxxxxxxxxxxxxx> wrote in message
> news:BUSAf.1305$Z3.347@xxxxxxxxxxxxxxxxxxxxxxx
>> The center conductor of the coax is acts a small broadcast antenna
>> (as well as a receiver) the outer shield serves to contain the
>> signal on the center conductor to prevent both radiated signal
>> leakage and reception of over-the-air signals. The exposed end of
>> the cable or splitter connection is breaks the "seal" on the system
>> and allows for leakage and reception of unwanted signals. The
>> terminator acts like a lid on jar and maintains the cables impedance.
>>
>> From:bruno.lerer@xxxxxxxxx
>> bruno.lerer@xxxxxxxxx
>>
>>> "> A caveat --
>>>
>>>> In a setup such as yours, each unused outlet should have a 75 ohm
>>>> terminator.  Radio Shack has them.  Unterminated cables can mess up
>>>> the signal to the active devices on the network.
>>>
>>>> SJF
>>>
>>> That goes for any unused connections on the spliter(s) as well. "
>>>
>>> Wow, for someone who is regulary considered by his friends as a more
>>> or less maven, I now feel unbelievably ignorant ): I guess ignorance
>>> is relative... I have never heard of 75 ohm terminators, nor of the
>>> problems caused by unterminated cables and unused connections on
>>> splitters.  As I mentioned in another response - learn something new
>>> every day.


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