What kind of cable is this?

[Marshall]

Hello,

I was out walking home from work yesterday here in Santa Clara, CA
when I stumbled across a large spool of cabling by the side of the
road. It appeared to have tumbled out the back of a truck as the
plastic spool was scraped and cracked in places. I'm hoping someone
can tell me what it's for. Here's a picture of it:

http://mavra.perilith.com/~marshall/mystery_cable/mystery-cable-large.jpg

The innermost bit is a copper cable ~1.5 mm in diameter. Surrounding
this are two helically wound clear plastic tubes. They appear empty.
I had a look at them with a hand lens and didn't see anything in them,
so I'm guessing that they're there to isolate the aforementioned
copper cable from the non-magnetic (i checked), copper colored braided
sheathing. Around this sheathing is a black and white plastic braided
sheathing.

Thank in advance =)

-mt

 

[Marshall]

"Watson A.Name - \"Watt Sun, the Dark Remover\"" <NOSPAM@dslextreme.com> wrote in message news:<10p9j1dra6v3681@corp.supernews.com>...

snip
Well, he would hae to measure the impedance or calculate it from the
dimensions of the center conductor, dielectric and shield. I
guesstimate that it's a low loss 50 ohm coax.

Hey All,

Thanks for all the educated guesses. I'll closely inspect the big
black plastic reel it's on when I get home from work today for part
#'s. Yeah, this would've been a smart place to look...(blush).

rgds,

-mt

 

marshall@perilith.com (Marshall) wrote:

http://mavra.perilith.com/~marshall/mystery_cable/mystery-cable-large.jpg

All the air-dielectric cable I've ever seen has another plastic tube
between the spacers and the braid, to keep the braid round in
cross-section instead of oval. Let us know what you find for part
numbers...

 

[Marshall]

dplatt@radagast.org (Dave Platt) wrote in message news:<10pa4a7tmufu51a@corp.supernews.com>...

snip
At high frequencies, the loss in the diaelectric is significant.
My guess is it's coax intended for use at very high frequencies.

Yup. I don't know what specific type this is, but it's an
air-dielectric RF cable. The spacer tubes are probably polyethylene
or something like that. Likely intended for high-UHF and microwave
frequencies. As it appears not to have any sort of waterproof outer
jacket, it's certainly for indoor applications only... perhaps
intended to be pulled through a conduit of some sort.

Wow, great, so I have 100' or so of indoor UHF or microwave ready RF cable.
Now let's see... you can cook with microwaves, then there's those
microwave `relay' towers dotted on the hills around me and... Ummm... I
seem to remember having a big, goofy UHF dial on my ancient TV set... So
what in the Wide Wide World of Sports does one do with 100' of this stuff?!

-mt

 

Ross Herbert <rherber1@bigpond.net.au> wrote:

marshall@perilith.com (Marshall) wrote:
what in the Wide Wide World of Sports does one do with 100' of this stuff?!

Before we can tell you that you have to find out exactly what its
specification is. So unless you can find a type number and
manufacturer then anyone's guess as to application is not going to be
entirely accurate.. However, you could possibly use it for esoteric
interconnects on your hi-fi system but whether this would sound better
is debatable.

What Ross said. My first thought on "what to do with low-loss coax
without a spec" was "audio interconnects", as without a spec it's
impossible to know if it'll work in a particular RF application.

 

[Jamie]

that is thread wrap, and at my present full time job we
do make that from time to time.
RG-62 (93 ohms)


William wrote:

marshall@perilith.com (Marshall) wrote:

http://mavra.perilith.com/~marshall/mystery_cable/mystery-cable-large.jpg


All the air-dielectric cable I've ever seen has another plastic tube
between the spacers and the braid, to keep the braid round in
cross-section instead of oval. Let us know what you find for part
numbers...

 

[Watson A.Name - \"Watt Su]

"Marshall" <marshall@perilith.com> wrote in message
news:1aedc422.0411122037.5166ffe4@posting.google.com...

dplatt@radagast.org (Dave Platt) wrote in message
news:<10pa4a7tmufu51a@corp.supernews.com>...
snip
At high frequencies, the loss in the diaelectric is significant.
My guess is it's coax intended for use at very high frequencies.

Yup. I don't know what specific type this is, but it's an
air-dielectric RF cable. The spacer tubes are probably polyethylene
or something like that. Likely intended for high-UHF and microwave
frequencies. As it appears not to have any sort of waterproof outer
jacket, it's certainly for indoor applications only... perhaps
intended to be pulled through a conduit of some sort.

Wow, great, so I have 100' or so of indoor UHF or microwave ready RF
cable.
Now let's see... you can cook with microwaves, then there's those
microwave `relay' towers dotted on the hills around me and... Ummm...
I
seem to remember having a big, goofy UHF dial on my ancient TV set...
So
what in the Wide Wide World of Sports does one do with 100' of this
stuff?!

Hey, it's that time of the year. You can tie those bundles of leaves
and trash up with it. ;-)

> -mt

 

[Dave Platt]

The innermost bit is a copper cable ~1.5 mm in diameter. Surrounding
this are two helically wound clear plastic tubes. They appear empty.
I had a look at them with a hand lens and didn't see anything in them,
so I'm guessing that they're there to isolate the aforementioned
copper cable from the non-magnetic (i checked), copper colored braided
sheathing. Around this sheathing is a black and white plastic braided
sheathing.

At high frequencies, the loss in the diaelectric is significant.
My guess is it's coax intended for use at very high frequencies.

Yup. I don't know what specific type this is, but it's an
air-dielectric RF cable. The spacer tubes are probably polyethylene
or something like that. Likely intended for high-UHF and microwave
frequencies. As it appears not to have any sort of waterproof outer
jacket, it's certainly for indoor applications only... perhaps
intended to be pulled through a conduit of some sort.

--
Dave Platt <dplatt@radagast.org> AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

 

[Ross Herbert]

On Sat, 13 Nov 2004 12:38:08 -0800, "Watson A.Name - \"Watt Sun, the
Dark Remover\"" <NOSPAM@dslextreme.com> wrote:

"Ross Herbert" <rherber1@bigpond.net.au> wrote in message
news:5c5bp01159q9n15ib73b8pbhrn9icd40b6@4ax.com...
On 12 Nov 2004 20:37:19 -0800, marshall@perilith.com (Marshall) wrote:

dplatt@radagast.org (Dave Platt) wrote in message
news:<10pa4a7tmufu51a@corp.supernews.com>...
snip
At high frequencies, the loss in the diaelectric is significant.
My guess is it's coax intended for use at very high frequencies.

Yup. I don't know what specific type this is, but it's an
air-dielectric RF cable. The spacer tubes are probably
polyethylene
or something like that. Likely intended for high-UHF and microwave
frequencies. As it appears not to have any sort of waterproof
outer
jacket, it's certainly for indoor applications only... perhaps
intended to be pulled through a conduit of some sort.

Wow, great, so I have 100' or so of indoor UHF or microwave ready RF
cable.
Now let's see... you can cook with microwaves, then there's those
microwave `relay' towers dotted on the hills around me and... Ummm...
I
seem to remember having a big, goofy UHF dial on my ancient TV set...
So
what in the Wide Wide World of Sports does one do with 100' of this
stuff?!

-mt
Before we can tell you that you have to find out exactly what its
specification is. So unless you can find a type number and
manufacturer then anyone's guess as to application is not going to be
entirely accurate.. However, you could possibly use it for esoteric
interconnects on your hi-fi system but whether this would sound better
is debatable.

With the dielectric allowing the copper braid to move in relation to the
center conductor, the cable could be microphonic if it was used with a
high Z microphone.

Surely you jest...

The main reason for a centre conductor of tightly twisted small guage
strands and a very densely woven braid is to provide good flexibility
together with a reduction in the generation of spurii, as would be the
case when used as a flexible interconnect. The use of a double spiral
continuous spacer also ensures good flexibility as well as ensuring a
constant spacing when the cable is undergoing flexing.

If this cable was microphonic at audio frequencies due to slight
changes in the postional relationship of the centre conductor and the
outer screen, how do you think these changes would affect its
operation if it were used at UHF? Surely, - if you are correct, - it
would create major problems at higher frequencies by altering
characteristic impedance, noise generation etc all of which would
probably be most evident.

 

[Watson A.Name - \"Watt Su]

"Ross Herbert" <rherber1@bigpond.net.au> wrote in message
news:gf2hp0d82ds5k7ltnn3lu7i2fg008ndatk@4ax.com...

On Sat, 13 Nov 2004 12:38:08 -0800, "Watson A.Name - \"Watt Sun, the
Dark Remover\"" <NOSPAM@dslextreme.com> wrote:


"Ross Herbert" <rherber1@bigpond.net.au> wrote in message
news:5c5bp01159q9n15ib73b8pbhrn9icd40b6@4ax.com...
On 12 Nov 2004 20:37:19 -0800, marshall@perilith.com (Marshall)
wrote:

dplatt@radagast.org (Dave Platt) wrote in message
news:<10pa4a7tmufu51a@corp.supernews.com>...
snip
At high frequencies, the loss in the diaelectric is
significant.
My guess is it's coax intended for use at very high
frequencies.

Yup. I don't know what specific type this is, but it's an
air-dielectric RF cable. The spacer tubes are probably
polyethylene
or something like that. Likely intended for high-UHF and
microwave
frequencies. As it appears not to have any sort of waterproof
outer
jacket, it's certainly for indoor applications only... perhaps
intended to be pulled through a conduit of some sort.

Wow, great, so I have 100' or so of indoor UHF or microwave ready
RF
cable.
Now let's see... you can cook with microwaves, then there's those
microwave `relay' towers dotted on the hills around me and...
Ummm...
I
seem to remember having a big, goofy UHF dial on my ancient TV
set...
So
what in the Wide Wide World of Sports does one do with 100' of
this
stuff?!

-mt
Before we can tell you that you have to find out exactly what its
specification is. So unless you can find a type number and
manufacturer then anyone's guess as to application is not going to
be
entirely accurate.. However, you could possibly use it for esoteric
interconnects on your hi-fi system but whether this would sound
better
is debatable.

With the dielectric allowing the copper braid to move in relation to
the
center conductor, the cable could be microphonic if it was used with
a
high Z microphone.


Surely you jest...

The main reason for a centre conductor of tightly twisted small guage
strands and a very densely woven braid is to provide good flexibility
together with a reduction in the generation of spurii, as would be the
case when used as a flexible interconnect. The use of a double spiral
continuous spacer also ensures good flexibility as well as ensuring a
constant spacing when the cable is undergoing flexing.

If this cable was microphonic at audio frequencies due to slight
changes in the postional relationship of the centre conductor and the
outer screen, how do you think these changes would affect its
operation if it were used at UHF? Surely, - if you are correct, - it
would create major problems at higher frequencies by altering
characteristic impedance, noise generation etc all of which would
probably be most evident.

Well, I've never seen a coax with as little 'jacket' as this one.
Which leads me to believe the shield can move much more than if it had a
decent jacket. Nothing like trying it sometime, right?

 

[Hal Murray]

The innermost bit is a copper cable ~1.5 mm in diameter. Surrounding
this are two helically wound clear plastic tubes. They appear empty.
I had a look at them with a hand lens and didn't see anything in them,
so I'm guessing that they're there to isolate the aforementioned
copper cable from the non-magnetic (i checked), copper colored braided
sheathing. Around this sheathing is a black and white plastic braided
sheathing.

At high frequencies, the loss in the diaelectric is significant.
My guess is it's coax intended for use at very high frequencies.

I've seen drawing of rings of foam spaced along the coax every
few diameters.

--
The suespammers.org mail server is located in California. So are all my
other mailboxes. Please do not send unsolicited bulk e-mail or unsolicited
commercial e-mail to my suespammers.org address or any of my other addresses.
These are my opinions, not necessarily my employer's. I hate spam.

 

[Watson A.Name - \"Watt Su]

"Marshall" <marshall@perilith.com> wrote in message
news:1aedc422.0411112335.6927b2a7@posting.google.com...

Hello,

I was out walking home from work yesterday here in Santa Clara, CA
when I stumbled across a large spool of cabling by the side of the
road. It appeared to have tumbled out the back of a truck as the
plastic spool was scraped and cracked in places. I'm hoping someone
can tell me what it's for. Here's a picture of it:


http://mavra.perilith.com/~marshall/mystery_cable/mystery-cable-large.jp

g

The innermost bit is a copper cable ~1.5 mm in diameter. Surrounding
this are two helically wound clear plastic tubes. They appear empty.
I had a look at them with a hand lens and didn't see anything in them,
so I'm guessing that they're there to isolate the aforementioned
copper cable from the non-magnetic (i checked), copper colored braided
sheathing. Around this sheathing is a black and white plastic braided
sheathing.

Thank in advance =)

It's definitely low loss coaxial cable, for UHF or higher freqs. And
it's definitely _not_ made for outdoor use! The cable reel should give
you some info or numbers to indicate the brand and type of cable.



> -mt

 

[Ross Herbert]

On 11 Nov 2004 23:35:52 -0800, marshall@perilith.com (Marshall) wrote:

Hello,

I was out walking home from work yesterday here in Santa Clara, CA
when I stumbled across a large spool of cabling by the side of the
road. It appeared to have tumbled out the back of a truck as the
plastic spool was scraped and cracked in places. I'm hoping someone
can tell me what it's for. Here's a picture of it:

http://mavra.perilith.com/~marshall/mystery_cable/mystery-cable-large.jpg

The innermost bit is a copper cable ~1.5 mm in diameter. Surrounding
this are two helically wound clear plastic tubes. They appear empty.
I had a look at them with a hand lens and didn't see anything in them,
so I'm guessing that they're there to isolate the aforementioned
copper cable from the non-magnetic (i checked), copper colored braided
sheathing. Around this sheathing is a black and white plastic braided
sheathing.

Thank in advance =)

-mt

There are a couple of clues from the pic.

It is coaxial cable with a stranded centre conductor and a high
density copper overall screen. The helically wound teflon (PTFE)
spacer tape ensures good flexibility together with the stranded centre
conductor. The fact that it has an outer sheath of probably nylon
indicates it is intended for flexible interconnects. Unfortunately,
without a part number or manufacturer name the operational
characteristics would be a guess.

 

[Watson A.Name - \"Watt Su]

"Ross Herbert" <rherber1@bigpond.net.au> wrote in message
news:k189p0ld10cnrnjbiu3up88gnh040hhcip@4ax.com...

On 11 Nov 2004 23:35:52 -0800, marshall@perilith.com (Marshall) wrote:

Hello,

I was out walking home from work yesterday here in Santa Clara, CA
when I stumbled across a large spool of cabling by the side of the
road. It appeared to have tumbled out the back of a truck as the
plastic spool was scraped and cracked in places. I'm hoping someone
can tell me what it's for. Here's a picture of it:


http://mavra.perilith.com/~marshall/mystery_cable/mystery-cable-large.j
pg

The innermost bit is a copper cable ~1.5 mm in diameter. Surrounding
this are two helically wound clear plastic tubes. They appear empty.
I had a look at them with a hand lens and didn't see anything in
them,
so I'm guessing that they're there to isolate the aforementioned
copper cable from the non-magnetic (i checked), copper colored
braided
sheathing. Around this sheathing is a black and white plastic
braided
sheathing.

Thank in advance =)

-mt

There are a couple of clues from the pic.

It is coaxial cable with a stranded centre conductor and a high
density copper overall screen. The helically wound teflon (PTFE)
spacer tape ensures good flexibility together with the stranded centre
conductor. The fact that it has an outer sheath of probably nylon
indicates it is intended for flexible interconnects. Unfortunately,
without a part number or manufacturer name the operational
characteristics would be a guess.

Well, he would hae to measure the impedance or calculate it from the
dimensions of the center conductor, dielectric and shield. I
guesstimate that it's a low loss 50 ohm coax.

 

[Ross Herbert]

On 12 Nov 2004 20:37:19 -0800, marshall@perilith.com (Marshall) wrote:

dplatt@radagast.org (Dave Platt) wrote in message news:<10pa4a7tmufu51a@corp.supernews.com>...
snip
At high frequencies, the loss in the diaelectric is significant.
My guess is it's coax intended for use at very high frequencies.

Yup. I don't know what specific type this is, but it's an
air-dielectric RF cable. The spacer tubes are probably polyethylene
or something like that. Likely intended for high-UHF and microwave
frequencies. As it appears not to have any sort of waterproof outer
jacket, it's certainly for indoor applications only... perhaps
intended to be pulled through a conduit of some sort.

Wow, great, so I have 100' or so of indoor UHF or microwave ready RF cable.
Now let's see... you can cook with microwaves, then there's those
microwave `relay' towers dotted on the hills around me and... Ummm... I
seem to remember having a big, goofy UHF dial on my ancient TV set... So
what in the Wide Wide World of Sports does one do with 100' of this stuff?!

-mt
Before we can tell you that you have to find out exactly what its

specification is. So unless you can find a type number and
manufacturer then anyone's guess as to application is not going to be
entirely accurate.. However, you could possibly use it for esoteric
interconnects on your hi-fi system but whether this would sound better
is debatable.

 

[Watson A.Name - \"Watt Su]

"Ross Herbert" <rherber1@bigpond.net.au> wrote in message
news:5c5bp01159q9n15ib73b8pbhrn9icd40b6@4ax.com...

On 12 Nov 2004 20:37:19 -0800, marshall@perilith.com (Marshall) wrote:

dplatt@radagast.org (Dave Platt) wrote in message
news:<10pa4a7tmufu51a@corp.supernews.com>...
snip
At high frequencies, the loss in the diaelectric is significant.
My guess is it's coax intended for use at very high frequencies.

Yup. I don't know what specific type this is, but it's an
air-dielectric RF cable. The spacer tubes are probably
polyethylene
or something like that. Likely intended for high-UHF and microwave
frequencies. As it appears not to have any sort of waterproof
outer
jacket, it's certainly for indoor applications only... perhaps
intended to be pulled through a conduit of some sort.

Wow, great, so I have 100' or so of indoor UHF or microwave ready RF
cable.
Now let's see... you can cook with microwaves, then there's those
microwave `relay' towers dotted on the hills around me and... Ummm...
I
seem to remember having a big, goofy UHF dial on my ancient TV set...
So
what in the Wide Wide World of Sports does one do with 100' of this
stuff?!

-mt
Before we can tell you that you have to find out exactly what its
specification is. So unless you can find a type number and
manufacturer then anyone's guess as to application is not going to be
entirely accurate.. However, you could possibly use it for esoteric
interconnects on your hi-fi system but whether this would sound better
is debatable.

With the dielectric allowing the copper braid to move in relation to the
center conductor, the cable could be microphonic if it was used with a
high Z microphone.