Quad shield coax & dielectric?
 

75-ohm RG-6 coax: quad shield differs from "standard" RG-6 in that the
dielectric is reduced in diameter to accomodate the extra shielding.

How does this affect the performance? I'm looking at 1 GHz (HDTV use).

Thanks.

Quad shield coax & dielectric?
 

On 3/14/2014 6:51 PM, Bob E. wrote:
75-ohm RG-6 coax: quad shield differs from "standard" RG-6 in that the
dielectric is reduced in diameter to accomodate the extra shielding.

How does this affect the performance? I'm looking at 1 GHz (HDTV use).

Thanks.


How are you going to use it for HDTV? HDTV is a TV signal protocol, not
a communications method.

--
==================
Remove the "x" from my email address
Jerry, AI0K

==================

Quad shield coax & dielectric?
 

How are you going to use it for HDTV? HDTV is a TV signal protocol, not
a communications method.

Not to be rude, but it's a simple question asked. The answer doesn't involve
the use to which it will be put.

Just trying to keep replies on-topic...

Quad shield coax & dielectric?
 

75 ohm cable with a loss of ~6db/30m at 1GHz

Quad shield coax & dielectric?
 

Bob E wrote:
How are you going to use it for HDTV? HDTV is a TV signal protocol, not
a communications method.

Not to be rude, but it's a simple question asked. The answer doesn't involve
the use to which it will be put.

But sure that does matter. Especially the signal frequency at which
you will use it, and the tolerable losses in the run of cable.

"HDTV" by itself does not tell enough. It could be terristrial broadcast,
cable TV, satellite TV.

Each of them has different characteristics w.r.t. frequencies in use
and losses that are tolerable.

Quad shield coax & dielectric?
 

In message ,
Bob E. writes
75-ohm RG-6 coax: quad shield differs from "standard" RG-6 in that the
dielectric is reduced in diameter to accomodate the extra shielding.

How does this affect the performance? I'm looking at 1 GHz (HDTV use).

Thanks.

I note that there have been a some replies, but none seem to make much
attempt at answering your question.

RG6Q is used extensively in the UK cable TV industry as 'drop' cable -
ie from the taps in the street cabinet to the home. It is used to
provide a high degree of immunity from ingress of interfering signals -
especially those at the lower frequencies (in the reverse path part of
the spectrum - typically between 5 and 65MHz). RG6 is not a particularly
low-loss cable, and for long drop runs, RG11 is sometimes used.

As for the attenuation differences between RG6 and RG6Q, I've done a bit
of Googling, and I can't see anything which is immediately pointed out.
Even on this site
http://www.ehow.com/list_7605813_difference-between-rg6-rg6q.html
all it says is that "RG-6 and RG-6Q share nearly the exact same outer
dimensions and have similar flexibility. RG-6Q is slightly stiffer due
to the increased amount of inner shielding".

I suspect that even if the diameter of the RG6Q dielectric is slightly
less (something which I've never really noticed) - requiring a slightly
thinner inner conductor in order to preserve the Zo - the increase of
attenuation won't be very much. However, I'm sure that a bit more
intensive Googling on RG6 physical and electrical specs will reveal the
true answer!
--
Ian

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Quad shield coax & dielectric?
 

On 3/15/2014 1:29 AM, Bob E. wrote:
How are you going to use it for HDTV? HDTV is a TV signal protocol, not
a communications method.

Not to be rude, but it's a simple question asked. The answer doesn't involve
the use to which it will be put.

Just trying to keep replies on-topic...


Yes, it does. The question was completely on topic. How you use it
will determine if RG6-quad is usable of your needs or not.


--
==================
Remove the "x" from my email address
Jerry Stuckle

==================

Quad shield coax & dielectric?
 

On 3/15/2014 9:18 AM, Ian Jackson wrote:
In message ,
Bob E. writes
75-ohm RG-6 coax: quad shield differs from "standard" RG-6 in that the
dielectric is reduced in diameter to accomodate the extra shielding.

How does this affect the performance? I'm looking at 1 GHz (HDTV use).

Thanks.

I note that there have been a some replies, but none seem to make much
attempt at answering your question.

RG6Q is used extensively in the UK cable TV industry as 'drop' cable -
ie from the taps in the street cabinet to the home. It is used to
provide a high degree of immunity from ingress of interfering signals -
especially those at the lower frequencies (in the reverse path part of
the spectrum - typically between 5 and 65MHz). RG6 is not a particularly
low-loss cable, and for long drop runs, RG11 is sometimes used.

As for the attenuation differences between RG6 and RG6Q, I've done a bit
of Googling, and I can't see anything which is immediately pointed out.
Even on this site
http://www.ehow.com/list_7605813_difference-between-rg6-rg6q.html
all it says is that "RG-6 and RG-6Q share nearly the exact same outer
dimensions and have similar flexibility. RG-6Q is slightly stiffer due
to the increased amount of inner shielding".

I suspect that even if the diameter of the RG6Q dielectric is slightly
less (something which I've never really noticed) - requiring a slightly
thinner inner conductor in order to preserve the Zo - the increase of
attenuation won't be very much. However, I'm sure that a bit more
intensive Googling on RG6 physical and electrical specs will reveal the
true answer!

No one has answered his question because the information is insufficient.

FYI - my company (a home automation company) installs thousands of feet
of coax every year (even more twisted pair). But we never specify what
to use until we know how it is being used.

Additionally, it depends if he needs to send send power over the coax
also, and if so, how much.

For instance, the new specs for HDTV (Ultra-hi-def, 3D at 240
frames/sec) require bandwidths of up to 18Ghz. It's something we have
to take into consideration on ANY installation.

Just saying it's going to be used for HDTV is not sufficient.

--
==================
Remove the "x" from my email address
Jerry, AI0K

==================

Quad shield coax & dielectric?
 

I note that there have been a some replies, but none seem to make much
attempt at answering your question.

THANK YOU IAN!! A thousand points for noting this.

RG6Q is used extensively in the UK cable TV industry as 'drop' cable -
ie from the taps in the street cabinet to the home. It is used to
provide a high degree of immunity from ingress of interfering signals -
especially those at the lower frequencies (in the reverse path part of
the spectrum - typically between 5 and 65MHz). RG6 is not a particularly
low-loss cable, and for long drop runs, RG11 is sometimes used.

As for the attenuation differences between RG6 and RG6Q, I've done a bit
of Googling, and I can't see anything which is immediately pointed out.
Even on this site
http://www.ehow.com/list_7605813_difference-between-rg6-rg6q.html
all it says is that "RG-6 and RG-6Q share nearly the exact same outer
dimensions and have similar flexibility. RG-6Q is slightly stiffer due
to the increased amount of inner shielding".

And another thousand points for answering the question--which was about the
cable's specs, NOT ABOUT ITS APPROPRIATENESS FOR A SPECIFIC APPLICATION.

I suspect that even if the diameter of the RG6Q dielectric is slightly
less (something which I've never really noticed) - requiring a slightly
thinner inner conductor in order to preserve the Zo - the increase of
attenuation won't be very much. However, I'm sure that a bit more
intensive Googling on RG6 physical and electrical specs will reveal the
true answer!
Ian

The question was how does RG6 compare to RG6Q, specifically whether or not
the reduced diameter of the dielectric effects its specifications.

Best to you.

Quad shield coax & dielectric?
 

In message , Jerry Stuckle
writes
On 3/15/2014 9:18 AM, Ian Jackson wrote:
In message ,
Bob E. writes
75-ohm RG-6 coax: quad shield differs from "standard" RG-6 in that the
dielectric is reduced in diameter to accomodate the extra shielding.

How does this affect the performance? I'm looking at 1 GHz (HDTV use).

Thanks.

I note that there have been a some replies, but none seem to make much
attempt at answering your question.

RG6Q is used extensively in the UK cable TV industry as 'drop' cable -
ie from the taps in the street cabinet to the home. It is used to
provide a high degree of immunity from ingress of interfering signals -
especially those at the lower frequencies (in the reverse path part of
the spectrum - typically between 5 and 65MHz). RG6 is not a particularly
low-loss cable, and for long drop runs, RG11 is sometimes used.

As for the attenuation differences between RG6 and RG6Q, I've done a bit
of Googling, and I can't see anything which is immediately pointed out.
Even on this site
http://www.ehow.com/list_7605813_difference-between-rg6-rg6q.html
all it says is that "RG-6 and RG-6Q share nearly the exact same outer
dimensions and have similar flexibility. RG-6Q is slightly stiffer due
to the increased amount of inner shielding".

I suspect that even if the diameter of the RG6Q dielectric is slightly
less (something which I've never really noticed) - requiring a slightly
thinner inner conductor in order to preserve the Zo - the increase of
attenuation won't be very much. However, I'm sure that a bit more
intensive Googling on RG6 physical and electrical specs will reveal the
true answer!

No one has answered his question because the information is insufficient.

FYI - my company (a home automation company) installs thousands of feet
of coax every year (even more twisted pair). But we never specify what
to use until we know how it is being used.

Additionally, it depends if he needs to send send power over the coax
also, and if so, how much.

For instance, the new specs for HDTV (Ultra-hi-def, 3D at 240
frames/sec) require bandwidths of up to 18Ghz. It's something we have
to take into consideration on ANY installation.

Just saying it's going to be used for HDTV is not sufficient.

My immediate lateral-thinking guess is that the OP has acquired some
RG6Q, and is wondering whether he can use it as antenna drop cable for
UHF TV (which, in the UK, includes HD). He has specifically said that
it's for use at less than 1GHz. His main concern is probably that
quad-shield might be a more lossy than RG6 (which indeed it could be as
a smaller diameter dielectric would require a smaller diameter inner in
order to maintain a Zo of 75 ohms, and this would increase the
attenuation). Of course, he could also be concerned about some of the
many other parameters - but I suspect not. If it's not attenuation
that's concerning him, I'm sure he will tell us.
--
Ian

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