RG6 and RG59
 

Sorry, I strongly suspect this is a very old can of worms I'm exhuming, but
here goes...

The web is full of advice (and noise) about RG6 being better than RG59, but a
small proportion of experience-based postings suggests that RG59 is often
adequate even where UHF signals are used, especially if it includes a foil
shield under a braid shield, and it has a foam dielectric. Less common is a
point suggesting that for HF (and perhaps CCTV and other video, as well as
S/PDIF digital audio) it might be better to use RG59 because its braid is
better at screening for these lower frequencies to get better SNR. This seems
to make sense, but it is it so? It appears to me that for domestic scales an
RG59 with the added foil shield and a foam dielectric might be the best coax
to use for low power signals, until some weakness dictates a specific
requirement for improvement.

RG6 and RG59
 

Lostgallifreyan wrote:
Sorry, I strongly suspect this is a very old can of worms I'm exhuming, but
here goes...

The web is full of advice (and noise) about RG6 being better than RG59, but a
small proportion of experience-based postings suggests that RG59 is often
adequate even where UHF signals are used, especially if it includes a foil
shield under a braid shield, and it has a foam dielectric. Less common is a
point suggesting that for HF (and perhaps CCTV and other video, as well as
S/PDIF digital audio) it might be better to use RG59 because its braid is
better at screening for these lower frequencies to get better SNR. This seems
to make sense, but it is it so? It appears to me that for domestic scales an
RG59 with the added foil shield and a foam dielectric might be the best coax
to use for low power signals, until some weakness dictates a specific
requirement for improvement.

If there was a "best" cable, there would be only one type. Some have
lower loss, some are more flexible, some have better weather resistance,
some have better shielding, some have a longer lifetime, some tolerate
temperature extremes better, some are more uniform, some are less
expensive, and so forth.

So deciding which cable is "better" requires a lot more information
about what your requirements are.

RG/U specs have long been abandoned by the military, so any manufacturer
can -- and do -- use these designations pretty much as they please. One
manufacturer's "RG-59/U" or "RG-59/U type" cable can be very different
from another's, in many important ways. So you have to look at the
specifications of the actual cables you're comparing.

That said, RG-6 is nominally larger in diameter than RG-59, so if
everything else is the same, it will have lower loss, be heavier, more
expensive, and less flexible.

Multiple shields are seldom important in amateur applications unless you
have some seriously strong local signal you need to keep out, or you
need to bundle several cables tightly together for a long run. Even
then, most amateurs will end up with a lot more signal leakage at other
points in the system than they'll get through a good quality single shield.

Speaking of shields, some cheaper cables have relatively poor coverage,
so a decent quality shield is sometimes a good investment. Adding foil
might make a poor shield better. But I have some popular foil-shielded
cable that has bizarre loss characteristics at around 400 MHz which vary
all over the map as the cable is flexed. So a poorly designed foil
shield can be worse than a decent braided one.

Foamed dielectric results in slightly lower loss. At UHF and below, this
is almost entirely due to the fact that it causes the center conductor
to be larger, reducing conductor loss. On the other hand, the velocity
factor and impedance vary a lot more from lot to lot than solid
dielectric cable, so in length-critical applications you'll need to be
able to measure the electrical length of each piece.

That's the five minute coax cable primer. If you dig a bit you'll find
out there's a lot more to it than this.

Roy Lewallen, W7EL

RG6 and RG59
 

Lostgallifreyan wrote in
:

....
sense, but it is it so?

I wrote some notes that you may find interesting at
http://www.vk1od.net/transmissionline/RG6/index.htm .

Owen

RG6 and RG59
 

Owen Duffy wrote in
:

Lostgallifreyan wrote in
:

...
sense, but it is it so?

I wrote some notes that you may find interesting at
http://www.vk1od.net/transmissionline/RG6/index.htm .

Owen


Very useful, though I'm still not clear about using it for HF. I found eBay
listing 270364333691 (worth seeing, low cost, good pictures and description),
but that shows a thin braid and film that I read might not be adequate for
shielding at HF. Low cost is great but I wonder if trying to get good
connections to aluminium braid will be more trouble than it's worth, if the
worth of a cable with a copper braid isn't that much higher. (Still looking
for one). The cable that seems most likely to work based on all I read is a
BT2002 cable with a double copper braid over a foam dielectric and stranded
core, but the cost is three times higher.

RG6 and RG59
 

Roy Lewallen wrote in
:

If there was a "best" cable, there would be only one type. Some have
lower loss, some are more flexible, some have better weather resistance,
some have better shielding, some have a longer lifetime, some tolerate
temperature extremes better, some are more uniform, some are less
expensive, and so forth.

So deciding which cable is "better" requires a lot more information
about what your requirements are.


If I went into most places selling cables I'd get laughed at if I took that
line, they'd say 'hie me to a research lab, if not an actual nunnery'. :) Not
that you're wrong, but if you want a single general purpose cable for HF and
VHF especially if stocking it for general sale, then there IS a 'best' cable,
defined simply by that which most likely serves the wide range of purposes at
a low price. Currently in the UK that cable seems to be RG6; few places like
to stock more than one type for RF if they think one will do. Perfectionism
is NOT the first base. It's reasonable to expect some standard without being
told to either become an expert or use a bell wire and stay in ignorance. RG6
works, but they sell it for VHF/UHF, not RF. I'm not so concerned with
moderate losses, but SNR maintained by good shielding matters to me.

I take your point about poor foil/braid shields being worse than good braids.
That's partly what drove my question. It seems to me that RG6 in all forms I
have found is optimised for VHF and higher. Nothing I've seen either before
or after that question has yet convinced me that RG6 is the better choice for
HF. I've seen plenty of posts saying it will work, but just as many saying
they've seen old RG59 cables doing fine at UHF too.

So far I think I'm likely to go with the more costly double braided BT2002.
Most posts I read stated that poor performance was usually due to
difficulties connecting firmly to the soft aluminium shield than to the
cable's own qualities. I suspect the extra cost for double copper braid will
be repaid in easier (soldered) connections and other savings elsewhere, plus
a certainty that it is effective at HF. I'm not going to be using it for UHF
(although I have done once, it worked ok for a long TV aerial extension), and
I've already used it for VHF with good results. Main thing with the BT2002 is
that it's old, there might be something directly equivalent made for British
Telecom data links now, perhaps thinner, or cheaper, or more flexible, but I
don't know how to check for that. I've seen a list of BT type cables but I
think it was as old as that cable is.

Last time I got the BT2002 I found it, didn't have to pay for it. The only
thing making me wary of it now is that it won't be free this time. :)

RG6 and RG59
 

Lostgallifreyan wrote:
Roy Lewallen wrote in
:

If there was a "best" cable, there would be only one type. Some have
lower loss, some are more flexible, some have better weather resistance,
some have better shielding, some have a longer lifetime, some tolerate
temperature extremes better, some are more uniform, some are less
expensive, and so forth.

So deciding which cable is "better" requires a lot more information
about what your requirements are.


If I went into most places selling cables I'd get laughed at if I took that
line, they'd say 'hie me to a research lab, if not an actual nunnery'. :) Not
that you're wrong, but if you want a single general purpose cable for HF and
VHF especially if stocking it for general sale, then there IS a 'best' cable,
defined simply by that which most likely serves the wide range of purposes at
a low price. Currently in the UK that cable seems to be RG6; few places like
to stock more than one type for RF if they think one will do. . .

Sounds like you have your answer, then.

Roy Lewallen, W7EL

RG6 and RG59
 

If I went into most places selling cables I'd get laughed at if I took that
line, they'd say 'hie me to a research lab, if not an actual nunnery'. :) Not
that you're wrong, but if you want a single general purpose cable for HF and
VHF especially if stocking it for general sale, then there IS a 'best' cable,
defined simply by that which most likely serves the wide range of purposes at
a low price. Currently in the UK that cable seems to be RG6; few places like
to stock more than one type for RF if they think one will do. Perfectionism
is NOT the first base. It's reasonable to expect some standard without being
told to either become an expert or use a bell wire and stay in ignorance. RG6
works, but they sell it for VHF/UHF, not RF. I'm not so concerned with
moderate losses, but SNR maintained by good shielding matters to me.


You seem to miss the point that one shop's RG6 (or most other RG cables)
may well not be the same as another's. So there is no definitive answer
to you question.

It is also very unlikely that 'good shielding' will have any effect on
SNR in most applications, other than due to increased loss if the
braiding is very very poor, or you are running the cable very close to a
source of broadband interference.

Jeff

RG6 and RG59
 

Roy Lewallen wrote in
:

Lostgallifreyan wrote:
Roy Lewallen wrote in
:

If there was a "best" cable, there would be only one type. Some have
lower loss, some are more flexible, some have better weather
resistance, some have better shielding, some have a longer lifetime,
some tolerate temperature extremes better, some are more uniform, some
are less expensive, and so forth.

So deciding which cable is "better" requires a lot more information
about what your requirements are.


If I went into most places selling cables I'd get laughed at if I took
that line, they'd say 'hie me to a research lab, if not an actual
nunnery'. :) Not that you're wrong, but if you want a single general
purpose cable for HF and VHF especially if stocking it for general
sale, then there IS a 'best' cable, defined simply by that which most
likely serves the wide range of purposes at a low price. Currently in
the UK that cable seems to be RG6; few places like to stock more than
one type for RF if they think one will do. . .

Sounds like you have your answer, then.

Roy Lewallen, W7EL


Yes, if I was using for UHF and perhaps VHF as they sell it for. But as far
as I know the older UG59 used a braid with better physical coverage and was
specified for HF as well. I'd rather get something this time that has good HF
shielding as priority, so I'm not convinced that RG6 is the right choice. A
bit of extra loss isn't as bad as poor shielding.

RG6 and RG59
 

Fred wrote in
:


If I went into most places selling cables I'd get laughed at if I took
that line, they'd say 'hie me to a research lab, if not an actual
nunnery'. :) Not that you're wrong, but if you want a single general
purpose cable for HF and VHF especially if stocking it for general
sale, then there IS a 'best' cable, defined simply by that which most
likely serves the wide range of purposes at a low price. Currently in
the UK that cable seems to be RG6; few places like to stock more than
one type for RF if they think one will do. Perfectionism is NOT the
first base. It's reasonable to expect some standard without being told
to either become an expert or use a bell wire and stay in ignorance.
RG6 works, but they sell it for VHF/UHF, not RF. I'm not so concerned
with moderate losses, but SNR maintained by good shielding matters to
me.


You seem to miss the point that one shop's RG6 (or most other RG cables)
may well not be the same as another's. So there is no definitive answer
to you question.


No, haven't missed that at all. Most of my time is spent looking at all the
RG6's out there and examinng that. Besides, most advice out there implies I
have to buy it and try it to be sure, which is stupid because it's cheaper
and faster to get a better cable! RG6 is specified for UHF, I want HF.

It is also very unlikely that 'good shielding' will have any effect on
SNR in most applications, other than due to increased loss if the
braiding is very very poor, or you are running the cable very close to a
source of broadband interference.


I've been told that braid makes a great deal of difference to common mode
noise pickup, and that while a thin foil and loose braid is fine at UHF it's
not to be expected to do the same for HF.

http://www.abccables.com/info-rg59-vs-rg6.html is one of the more descriptive
texts I read. No RG6 that I have found fits the description given there for
HF. RG59 does though, as does BT2002. I think I'll be going with that BT2002
anyway, never mind the expense. The waste of time trying to avoid it is alone
beginning to look more expensive than the price difference.

RG6 and RG59
 

Lostgallifreyan wrote:

Yes, if I was using for UHF and perhaps VHF as they sell it for. But as far
as I know the older UG59 used a braid with better physical coverage and was
specified for HF as well. I'd rather get something this time that has good HF
shielding as priority, so I'm not convinced that RG6 is the right choice. A
bit of extra loss isn't as bad as poor shielding.

The standard for cable tv and satellite instalations is RG6 "quad shield",
which has a less dense braid, but a (almost) 100% aluminum foil shield.

The question is how do you connect to it? Commerical applications use special
crimp on connectors, you can solder it with the proper flux.

A friend brought some Radio Shack screw on PL-259 connectors that work fine
with it, but they are $6 each in the US, and unavailable here.

Geoff.

--
Geoffrey S. Mendelson, Jerusalem, Israel N3OWJ/4X1GM
New word I coined 12/13/09, "Sub-Wikipedia" adj, describing knowledge or
understanding, as in he has a sub-wikipedia understanding of the situation.
i.e possessing less facts or information than can be found in the Wikipedia.

RG6 and RG59
 

"Geoffrey S. Mendelson" wrote in
:

Lostgallifreyan wrote:

Yes, if I was using for UHF and perhaps VHF as they sell it for. But as
far as I know the older UG59 used a braid with better physical coverage
and was specified for HF as well. I'd rather get something this time
that has good HF shielding as priority, so I'm not convinced that RG6
is the right choice. A bit of extra loss isn't as bad as poor
shielding.

The standard for cable tv and satellite instalations is RG6 "quad
shield", which has a less dense braid, but a (almost) 100% aluminum
foil shield.


As far I can tell from advice on HF, the thin foil doesn't shield as well at
HF as a thicker braid with good physical coverage.

The question is how do you connect to it? Commerical applications use
special crimp on connectors, you can solder it with the proper flux.

A friend brought some Radio Shack screw on PL-259 connectors that work
fine with it, but they are $6 each in the US, and unavailable here.


I found an RG6 at low cost with copper braid and Al foil (more likely
metalised plastic film) so I can solder ok with that, but I'm going to be
using this for HF, not UHF, and if anything, I want to include MF signals so
as I mentioned in other posts, I'm not convinced that RG6 is the best choice,
unless it's the only RF cable in the shop. :)

RG6 and RG59
 

I've been told that braid makes a great deal of difference to common mode
noise pickup, and that while a thin foil and loose braid is fine at UHF it's
not to be expected to do the same for HF.

Even if you accept the principle that foil is worse than braid for
common mode signals, where do you think these signals are coming from?
Unless the cables route close to the source of the interference then
your antenna is going to pick it up much more than any difference in
shielding.


http://www.abccables.com/info-rg59-vs-rg6.html is one of the more descriptive
texts I read. No RG6 that I have found fits the description given there for
HF. RG59 does though, as does BT2002. I think I'll be going with that BT2002
anyway, never mind the expense. The waste of time trying to avoid it is alone
beginning to look more expensive than the price difference.

I must admit I do not understand the theory that foil is worse than
braid at lower frequencies, foil gives 100% coverage and is usually in
addition to braid. Even if it the thickness of the foil that is in
question, I don't see how, according to the article that you linked to,
it " don't(sic) have the proper type of shielding ".

There may be an issue with terminating foil shields well but that is a
different matter.

RG6 and RG59
 

Jeff wrote in
:



I've been told that braid makes a great deal of difference to common
mode noise pickup, and that while a thin foil and loose braid is fine
at UHF it's not to be expected to do the same for HF.

Even if you accept the principle that foil is worse than braid for
common mode signals, where do you think these signals are coming from?
Unless the cables route close to the source of the interference then
your antenna is going to pick it up much more than any difference in
shielding.


True, but that's why I want it. It's to exclude HF noise made by anything in
the building. The antenna will be several tens of metres away. As the signals
I want are HF and perhaps high MF from that antenna, it seems unlikely that I
should go with a cable whose specs are too loosely defined, and all
interpretations of 'RG6' are now attempts to reduce cost while getting
acceptable performance at UHF.


http://www.abccables.com/info-rg59-vs-rg6.html is one of the more
descriptive texts I read. No RG6 that I have found fits the description
given there for HF. RG59 does though, as does BT2002. I think I'll be
going with that BT2002 anyway, never mind the expense. The waste of
time trying to avoid it is alone beginning to look more expensive than
the price difference.

I must admit I do not understand the theory that foil is worse than
braid at lower frequencies, foil gives 100% coverage and is usually in
addition to braid. Even if it the thickness of the foil that is in
question, I don't see how, according to the article that you linked to,
it " don't(sic) have the proper type of shielding ".


Well, that's why I'm questioning it here. Like Geoffrey Mendelson said in his
reply in the later thread on RG6 in this group, a lot of the posts I've seen
on the web say more about the posters making them. I think I'll get a better
signal here than on the web at large. No irritating forum signups before
posting, either.. That article does seem to have a few vague contradictions,
but I think the point about a thin foil that is adequate for UHF screening
being inadequate for HF is interesting, and I've seen that point claimed
before. I'm pretty sure I'm not going to get an answer for that from people
who are dealing with UHF or fast digital signals, and mainly from an
installer's point of view, if the equipment they're using will filter out HF
anyway. Their purpose is not the same as mine.

There may be an issue with terminating foil shields well but that is a
different matter.


I found an RG6 with copper braid, to take care of that. Cheap too, but only
if it works. If it doesn't it will be cheaper to go for better cable to start
with. I like that BT2002 with the double copper braid, but I'm not yet sure
if the difference justifies the cost, though judging by what some places
charge for RG6 it probably does..

RG6 and RG59
 

Lostgallifreyan wrote:
I found an RG6 with copper braid, to take care of that. Cheap too, but only
if it works. If it doesn't it will be cheaper to go for better cable to start
with. I like that BT2002 with the double copper braid, but I'm not yet sure
if the difference justifies the cost, though judging by what some places
charge for RG6 it probably does..

There also is the question of cost and availablity. I can go to Home Center
and buy for about $.50 a meter a decent quality RG6 quad shield. In other
places, you should be able to localy source it for less.

Radio type coax requires me to special order it at the local electronics
store, and it will be a lot more expensive and less likely to be what
I wanted.

I really do miss being in the US able to go into any one of 6 Radio
Shack stores near my home and buy RG8x (really just improved RG-58) or
RG-8 coax by the foot. It wasn't the best one could buy, it it was "good
enough".

I can only guess you situation, but if you can do it, I would just go
to a supplier you trust and buy RG6 and see if it works. While I'm sure if
you had the right equipment you could find differences in the noise that
comes through various RG6 versions, it may not be enough to matter.

Geoff.

--
Geoffrey S. Mendelson, Jerusalem, Israel N3OWJ/4X1GM
New word I coined 12/13/09, "Sub-Wikipedia" adj, describing knowledge or
understanding, as in he has a sub-wikipedia understanding of the situation.
i.e possessing less facts or information than can be found in the Wikipedia.

RG6 and RG59
 

"Geoffrey S. Mendelson" wrote in
:

I can only guess you situation, but if you can do it, I would just go
to a supplier you trust and buy RG6 and see if it works. While I'm sure if
you had the right equipment you could find differences in the noise that
comes through various RG6 versions, it may not be enough to matter.


Well, that's maybe first choice. Just haven't decided if I'll stump up the
£18 or wait and search a bit longer for more info.

My situation is an HF antenna that will bring a signal from several tens of
metres away, into a building with stuff likely to put RF at several
frequencies onto the line. I'll filter out what I don't want with a selective
'tuner' eventually, but whether I do that or not I still have to reduce
common mode noise that is in same band as signals I want. I'll be using
ferrite slugs to reduce this, but I learned that this works by blocking skin-
effect carriage of RF signals on the outside of the coax shield, reducing
common mode noise by making current in the shield balance that in the core.
This implies that when a skin effect carries current down the outside of the
shield, but is not equal (and inverse) to current in the core, it must be
balanced by current on the inside of the shield instead. In transmissions,
I'm told this can turn a shield into an emitter, and though I'm receiving the
inverse is true, so I don't want the shield to pick up local noise and feed
it to the input via imbalances between shield and core. So if this use of
ferrites relies on suppressing signals in skin effect current flow, and HF
skin effect thickness are thicker than those for UHF, it seems to follow that
a metallised plastic film is too thin. It appears that a shield for HF must
be at least twice as thick as the skin effect depth for HF. RG6's foil or
metallised plastic seems too thin, and while the braid is thick enough, its
physical coverage is poor. I think it's mostly there to ensure continuity of
foil as a guard against UHF noise when foil cracks on bending, and as a means
to anchor a connection.

RG6 and RG59
 

Lostgallifreyan wrote:


I've been told that braid makes a great deal of difference to common mode
noise pickup, and that while a thin foil and loose braid is fine at UHF it's
not to be expected to do the same for HF.

Are their any good references with test numbers on this? Been googling a
bit, haven't found anything definitive yet

- 73 de Mike N3LI -

RG6 and RG59
 

On Wed, 03 Feb 2010 11:41:18 -0500, Michael Coslo
wrote:

I've been told that braid makes a great deal of difference to common mode
noise pickup, and that while a thin foil and loose braid is fine at UHF it's
not to be expected to do the same for HF.

Are their any good references with test numbers on this? Been googling a
bit, haven't found anything definitive yet

Hi Mike,

With the CM performance being tied to foil application, such a
non-starter is bound to have only the whisp of academic research into
it if you expect to find test numbers. On the other hand, there's
sure to be a forest fire of testimonials.

To help in your search, try googling "cable transfer impedance." The
first page of responses should have a wealth of information.

73's
Richard Clark, KB7QHC

RG6 and RG59
 

Michael Coslo wrote in
:

Lostgallifreyan wrote:


I've been told that braid makes a great deal of difference to common
mode noise pickup, and that while a thin foil and loose braid is fine
at UHF it's not to be expected to do the same for HF.

Are their any good references with test numbers on this? Been googling a
bit, haven't found anything definitive yet

- 73 de Mike N3LI -


Not that I know of, I only saw this one:
http://www.bluejeanscable.com/articles/shielding.htm
It even describes cable transfer impedance so I guess it IS useful for other
than 'telling me what I want to hear'. :)

I just went for braided BT2002 because I know I can reuse it. I originally
found some in a telephone exchange skip, and had used it to extend UHF TV
antenna when I had a TV, many years ago, and later for a VHF dipole. I know
that a good braid covering is good for strong AF, so it seemes highly likely
that it will work on HF just as well if it's that good on frequencies on
either end of it.

RG6 and RG59
 

On Sun, 31 Jan 2010 08:47:29 -0600, Lostgallifreyan
wrote:

Roy Lewallen wrote in
m:

Lostgallifreyan wrote:
Roy Lewallen wrote in
:

If there was a "best" cable, there would be only one type. Some have
lower loss, some are more flexible, some have better weather
resistance, some have better shielding, some have a longer lifetime,
some tolerate temperature extremes better, some are more uniform, some
are less expensive, and so forth.

So deciding which cable is "better" requires a lot more information
about what your requirements are.


If I went into most places selling cables I'd get laughed at if I took
that line,

However he gave you the right answer to the question you asked.
There is no one best coax!
Are you just using it for receiving or transmitting as well. Typically
you don't find either of those cables used in ham stations, except to
feed Beverage receiving antennas.

I use a lot of "flooded" RG-6 with compression connectors for UHF
receiving. I use RG-8X (foil with shield) to the 40 meter, half wave
sloping dipoles. It's fairly rugged, very flexible, presents a low
profile to the wind and doesn't weight a lot. Its power handeling
capability is a bit low, but I haven't blown any out...yet, unlike
CNT-240.

they'd say 'hie me to a research lab, if not an actual
nunnery'. :)

Then perhaps you should purchase coax elsewhere?

Not that you're wrong, but if you want a single general
purpose cable for HF and VHF especially if stocking it for general
sale, then there IS a 'best' cable, defined simply by that which most
likely serves the wide range of purposes at a low price. Currently in
the UK that cable seems to be RG6; few places like to stock more than
one type for RF if they think one will do. . .

I take it then that this is not for an amateur radio station?


Sounds like you have your answer, then.

Roy Lewallen, W7EL


Yes, if I was using for UHF and perhaps VHF as they sell it for. But as far
as I know the older UG59 used a braid with better physical coverage and was
specified for HF as well. I'd rather get something this time that has good HF
shielding as priority, so I'm not convinced that RG6 is the right choice. A
bit of extra loss isn't as bad as poor shielding.

RG-6 is foil plus braid and it doesn't get much better than that.
However for HF my choice would be RG-8X (with foil plus braid- it
comes in many forms) although I use LMR-600.


Good luck,

Roger (K8RI)

RG6 and RG59
 

On Sun, 31 Jan 2010 08:56:41 -0600, Lostgallifreyan
wrote:

Fred wrote in
:


If I went into most places selling cables I'd get laughed at if I took
that line, they'd say 'hie me to a research lab, if not an actual
nunnery'. :) Not that you're wrong, but if you want a single general
purpose cable for HF and VHF especially if stocking it for general
sale, then there IS a 'best' cable, defined simply by that which most
likely serves the wide range of purposes at a low price. Currently in
the UK that cable seems to be RG6; few places like to stock more than
one type for RF if they think one will do. Perfectionism is NOT the
first base. It's reasonable to expect some standard without being told
to either become an expert or use a bell wire and stay in ignorance.
RG6 works, but they sell it for VHF/UHF, not RF. I'm not so concerned
with moderate losses, but SNR maintained by good shielding matters to
me.


You seem to miss the point that one shop's RG6 (or most other RG cables)
may well not be the same as another's. So there is no definitive answer
to you question.


No, haven't missed that at all. Most of my time is spent looking at all the
RG6's out there and examinng that. Besides, most advice out there implies I
have to buy it and try it to be sure, which is stupid because it's cheaper
and faster to get a better cable! RG6 is specified for UHF, I want HF.

I have 5 runs of RG-6 (foil plus braid) running in a conduit with 2
LMR-600 cables carrying 1500 watts of RF at HF. I also have 3
CAT6 network cables in there. None of them hear the others.


It is also very unlikely that 'good shielding' will have any effect on
SNR in most applications, other than due to increased loss if the
braiding is very very poor, or you are running the cable very close to a
source of broadband interference.


I've been told that braid makes a great deal of difference to common mode
noise pickup, and that while a thin foil and loose braid is fine at UHF it's
not to be expected to do the same for HF.

It's the shield, of which the braid is only part. Only if you are
running the RG-6 with other HF cables *might* you find a problem. As
I said above, I have 5 of them in the same conduit with cables
carrying 1500 watts of HF RF and there is no cross talk. That thin
foil is just fine at HF as well as UHF as long as it's not carrying
substantial power. Where you really need the extra shielding is at
very low frequency,or very high power. They do make quad shield RG-6
for receiving, but it's not a cable for high power transmitting. I'd
not put more than 100 watts into RG-6 of any configuration.

73 and good luck,

Roger (K8RI)



http://www.abccables.com/info-rg59-vs-rg6.html is one of the more descriptive
texts I read. No RG6 that I have found fits the description given there for
HF. RG59 does though, as does BT2002. I think I'll be going with that BT2002
anyway, never mind the expense. The waste of time trying to avoid it is alone
beginning to look more expensive than the price difference.

RG6 and RG59
 

On Sun, 31 Jan 2010 14:59:06 +0000 (UTC), "Geoffrey S. Mendelson"
wrote:

Lostgallifreyan wrote:

Yes, if I was using for UHF and perhaps VHF as they sell it for. But as far
as I know the older UG59 used a braid with better physical coverage and was
specified for HF as well. I'd rather get something this time that has good HF
shielding as priority, so I'm not convinced that RG6 is the right choice. A
bit of extra loss isn't as bad as poor shielding.

The standard for cable tv and satellite instalations is RG6 "quad shield",
which has a less dense braid, but a (almost) 100% aluminum foil shield.

The question is how do you connect to it? Commerical applications use special
crimp on connectors, you can solder it with the proper flux.

Compression fittings. Easy to install, strong, water proof, and about
50 cents each.


A friend brought some Radio Shack screw on PL-259 connectors that work fine
with it, but they are $6 each in the US, and unavailable here.

And a waste of money.
The problem with the compression fittings is you need a compression
tool to install them although a pair of the "duck billed" vise grips,
or even pliers could be adapted to do the job. You only need hold the
front and back of the connector and then push the pack part with the
seal into the front part...a distance of maybe 1/8" (4mm) . The
commercial tools are kinda pricey, but you can make one up out of a
pair of pliers and a bit of ingenuity.

73

Roger (K8RI)


Geoff.

RG6 and RG59
 

On Jan 29, 7:56*pm, Roy Lewallen wrote:
....
If there was a "best" cable, there would be only one type. Some have
lower loss, some are more flexible, some have better weather resistance,
some have better shielding, some have a longer lifetime, some tolerate
temperature extremes better, some are more uniform, some are less
expensive, and so forth.

So deciding which cable is "better" requires a lot more information
about what your requirements are.
....
Roy Lewallen, W7EL

Well said, Roy. I just purchased 2000 feet of "RG-6" coax. My main
goal was that I needed hundreds of feet of flooded coax with (good
shielding) that I could afford. The Commscope CATV aluminum foil/
braided coax that was available on eBay fit my needs perfectly.

I'm feeding my remote Beverages with it, as well as running medium
power to an inverted L on 160. Works great.

I'm convinced that no other coax at any price would have worked any
better.

73 Mike
W0BTU

RG6 and RG59
 

On Thu, 25 Mar 2010 02:36:46 -0400, Roger
wrote:

On Sun, 31 Jan 2010 08:47:29 -0600, Lostgallifreyan
wrote:

Roy Lewallen wrote in
om:

Lostgallifreyan wrote:
Roy Lewallen wrote in
:

If there was a "best" cable, there would be only one type. Some have
lower loss, some are more flexible, some have better weather
resistance, some have better shielding, some have a longer lifetime,
some tolerate temperature extremes better, some are more uniform, some
are less expensive, and so forth.

So deciding which cable is "better" requires a lot more information
about what your requirements are.


If I went into most places selling cables I'd get laughed at if I took
that line,

However he gave you the right answer to the question you asked.
There is no one best coax!
Are you just using it for receiving or transmitting as well. Typically
you don't find either of those cables used in ham stations, except to
feed Beverage receiving antennas.

I use a lot of "flooded" RG-6 with compression connectors for UHF
receiving. I use RG-8X (foil with shield) to the 40 meter, half wave
sloping dipoles. It's fairly rugged, very flexible, presents a low
profile to the wind and doesn't weight a lot. Its power handeling
capability is a bit low, but I haven't blown any out...yet, unlike
CNT-240.

they'd say 'hie me to a research lab, if not an actual
nunnery'. :)

Then perhaps you should purchase coax elsewhere?

Not that you're wrong, but if you want a single general
purpose cable for HF and VHF especially if stocking it for general
sale, then there IS a 'best' cable, defined simply by that which most
likely serves the wide range of purposes at a low price. Currently in
the UK that cable seems to be RG6; few places like to stock more than
one type for RF if they think one will do. . .

I take it then that this is not for an amateur radio station?


Sounds like you have your answer, then.

Roy Lewallen, W7EL


Yes, if I was using for UHF and perhaps VHF as they sell it for. But as far
as I know the older UG59 used a braid with better physical coverage and was
specified for HF as well. I'd rather get something this time that has good HF
shielding as priority, so I'm not convinced that RG6 is the right choice. A
bit of extra loss isn't as bad as poor shielding.

RG-6 is foil plus braid and it doesn't get much better than that.
However for HF my choice would be RG-8X (with foil plus braid- it
comes in many forms) although I use LMR-600.


Good luck,

Roger (K8RI)


I use whatever cheap **** Radio Shack has on sale.

DXCC
5BWAS

RG6 and RG59
 

Kickin' Ass and Takin' Names wrote:

I use whatever cheap **** Radio Shack has on sale.

You might try their coax too!

- 73 de Mike N3LI -