DX On Cable TV

[nd2023]

I remember a few years ago, whenever tropo hit, many of the over-the-air local channels such as ABC, NBC, CBS, etc. had co-channel interference on cable. Last week, there was a major tropo opening, but those channels were crystal clear. Do cable companies still receive local channels over the air?<P ID="signature">______________
17-year-old radio geek
Location: Princeton Junction, NJ
AIM: KewlDude471</P>

 

[crisisbroadcast]

> I remember a few years ago, whenever tropo hit, many of the
> over-the-air local channels such as ABC, NBC, CBS, etc. had
> co-channel interference on cable. Last week, there was a
> major tropo opening, but those channels were crystal clear.
> Do cable companies still receive local channels over the
> air?

This is mostly out of ignorance, but I'll try. I believe that cable companies may receive the major locals by microwave. I may be wrong, but I think I remember reading that somewhere.<P ID="signature">______________
</P>

 

[w9wi]

> > Do cable companies still receive local channels over the
> > air?
>
> This is mostly out of ignorance, but I'll try. I
> believe that cable companies may receive the major locals by
> microwave. I may be wrong, but I think I remember reading
> that somewhere.

Depends on the cable system.

Here in Nashville, Comcast uses fiber. At least for their Nashville/Davidson Co. customers, and I know the fiber system extends into some of the suburban counties as well. The Charter system in Madison, Wis. is also fiber connected to the locals.

(incidentially, both dish systems also receive Nashville locals via fiber and I'm sure that's also the case in many other markets)

Charter has a large receiving antenna setup in Ashland City, Tenn.. I don't know if that serves only their Cheatham Co. system, or if it also feeds the much larger system in Clarksville, or if Clarksville has a different off-air setup. (Charter used to have another antenna tower on the far southeast side of Clarksville but that was removed a few years ago)

At least one cable system in the Nashville market is believed to be carrying the locals' *digital* over-the-air signals. (makes a fair amount of sense, as the most popular channels here are on analog channels 2, 4, and 5 and susceptible to severe sporadic-E interference this time of year)

I have not heard of a cable system receiving locals via microwave. But there's no technical reason that shouldn't be possible. Nor any legal reason that I know of. There is a radio service set up that allows cable systems to microwave signals around, and I would imagine that service is occasionally used to bring local signals from a receiving antenna site to their headend.

 

[gr8oldies]

Our locals could be off the air for days and the cable subscribers wouldn't notice. The far outlying counties, I'm sure still recieve OTA. I can remember when the cable headend recieved FM OTA on all the original frequencies. It was like having a 200 foot tower at your disposal..DX heaven!<P ID="signature">______________
I'll get back to you when I think of a cute quote</P>

 

[JeremyAndrews]

> I remember a few years ago, whenever tropo hit, many of the
> over-the-air local channels such as ABC, NBC, CBS, etc. had
> co-channel interference on cable. Last week, there was a
> major tropo opening, but those channels were crystal clear.
> Do cable companies still receive local channels over the
> air?
>

2 would always get screwed up on my cable system. 2 is a distant local (WBBM Chicago) meaning the cable company gets some fuzz on it anyway.
<P ID="signature">______________
</P>

 

[JohnL]

> Our locals could be off the air for days and the cable
> subscribers wouldn't notice. The far outlying counties, I'm
> sure still recieve OTA. I can remember when the cable
> headend recieved FM OTA on all the original frequencies. It
> was like having a 200 foot tower at your disposal..DX
> heaven!
>
Very true. There have been instances here in Milwaukee that WTMJ-TV, ch. 4 would report to me that they would shut down their transmitter after 12 mid for maintenance, however tune to cable and they continue to broadcast.

WTMJ, and WITI feed Time-Warner directly via fiber optic cables. So when these stations have to do transmitter maintenance during the wee hours of the morning, they still continue their broadcasts on cable. People hooked up to cable TV don't notice it at all.

-John L.

 

[foreverchanges]

> > Our locals could be off the air for days and the cable
> > subscribers wouldn't notice. The far outlying counties,
> I'm
> > sure still recieve OTA. I can remember when the cable
> > headend recieved FM OTA on all the original frequencies.
> It
> > was like having a 200 foot tower at your disposal..DX
> > heaven!
> >
> Very true. There have been instances here in Milwaukee that
> WTMJ-TV, ch. 4 would report to me that they would shut down
> their transmitter after 12 mid for maintenance, however tune
> to cable and they continue to broadcast.
>
> WTMJ, and WITI feed Time-Warner directly via fiber optic
> cables. So when these stations have to do transmitter
> maintenance during the wee hours of the morning, they still
> continue their broadcasts on cable. People hooked up to
> cable TV don't notice it at all.
>
> -John L.
>


Didn't the cable companies used to use microwave? I know they did in Fayetteville, AR...where we recieved KOLR 10 from Springfield, MO, 2 or 3 Tulsa, OK channels, one from Pittsburg, KS and in the early 90's KARK from Little Rock. And I know where the microwave towers are on Mt. Sequoia....

 

[radio-outsider]

>
> Didn't the cable companies used to use microwave? I know
> they did in Fayetteville, AR...where we recieved KOLR 10
> from Springfield, MO, 2 or 3 Tulsa, OK channels, one from
> Pittsburg, KS and in the early 90's KARK from Little Rock.
> And I know where the microwave towers are on Mt. Sequoia....
>


I've worked in the cable industy since 1979. Used to be either off-air pickup or CARS band (Community Antenna Relay Service) microwave (point-to-point) for distant signals. Some interesting trickery was sometimes necessary to "phase-out" co-channel interference, but only worked when signal levels present were relatively consistant. Sometimes when the local signed off, you'd get a distant signal, but only if the threshold level of the channel processor was set low enough. If not, a stand-by carrier (blank screen) would kick in so that cable subscribers didn't see/hear hash.

These days most TV stations deliver their signal to area cable systems (and their transmitters for that matter) via fiber directly from the studio.

Perhaps the most interesting DX I've ever seen was in the San Francico Bay Area round about 1982. Our local system in the south bay received San Francisco locals via microwave. One evening I noticed some co-channel in the off-air's which is rare in the California climate. The co-channels got stronger and stronger until they overtook the locals. But what I was seeing was HBO and ESPN and MTV. Apparently the co-channel I was getting was on the CARS band feed, and the cable systems microwave was picking up a distant CARS feed. There was no way to figure out where it was coming from, because whoever was using it was transporting satellite signals, not TV stations.

 

[radio-outsider]

> Our locals could be off the air for days and the cable
> subscribers wouldn't notice. The far outlying counties, I'm
> sure still recieve OTA. I can remember when the cable
> headend recieved FM OTA on all the original frequencies. It
> was like having a 200 foot tower at your disposal..DX
> heaven!
>

Many years ago, the cable system in Lafayette, Indiana, 120 miles from Chicago, had an all-band FM processor with a quad-array antenna pointing at Chicago. The cable system was so leaky, that in many parts on town, the Chicago FM's came in like locals, spilling out of bad connectors and unsheilded electronics in the cable plant.

 

[biggrich]

This was many years ago in Indianapolis Comcast Cable would pull in WTIU/30 Bloomington, IN (PBS). Most nights when WTIU would sign off the St. Louis station on channel 30 would mysteriously appear. Some nights it was just a blue screen, but most nights the St. Louis station would pop in.

 

[TheDingo]

> > > Do cable companies still receive local channels over the
>
> > > air?
> >
> > This is mostly out of ignorance, but I'll try. I
> > believe that cable companies may receive the major locals
> by
> > microwave. I may be wrong, but I think I remember reading
>
> > that somewhere.
>
> Depends on the cable system.
>
> Here in Nashville, Comcast uses fiber. At least for their
> Nashville/Davidson Co. customers, and I know the fiber
> system extends into some of the suburban counties as well.
> The Charter system in Madison, Wis. is also fiber connected
> to the locals.
>
> (incidentially, both dish systems also receive Nashville
> locals via fiber and I'm sure that's also the case in many
> other markets)
>
> Charter has a large receiving antenna setup in Ashland City,
> Tenn.. I don't know if that serves only their Cheatham Co.
> system, or if it also feeds the much larger system in
> Clarksville, or if Clarksville has a different off-air
> setup. (Charter used to have another antenna tower on the
> far southeast side of Clarksville but that was removed a few
> years ago)
>
> At least one cable system in the Nashville market is
> believed to be carrying the locals' *digital* over-the-air
> signals. (makes a fair amount of sense, as the most popular
> channels here are on analog channels 2, 4, and 5 and
> susceptible to severe sporadic-E interference this time of
> year)
>
> I have not heard of a cable system receiving locals via
> microwave. But there's no technical reason that shouldn't
> be possible. Nor any legal reason that I know of. There is
> a radio service set up that allows cable systems to
> microwave signals around, and I would imagine that service
> is occasionally used to bring local signals from a receiving
> antenna site to their headend.
>

Mediacom of Ardmore TN / AL I beleive gets WSMV from Nashville over the air, some days it will be such a bad signal it is unwatchable, others there is just a slight fuzz to it, I could be wrong though<P ID="signature">______________
<div align="center"><a href="http://937thewolf.tk">

</P>

 

[RadioDaze]

Back in the mid-1990s, WUNC-TV 4, the local PBS station in Durham, NC, would always sign off at midnight. After the local channel 4 signed off one midnight several years ago, WYFF-TV 4 in Greenville, SC began airing in WUNC's place on the cable system (with some snow, but in color). That's the only time I've seen that on cable...every other time a station has signed off it was replaced by a black screen. Now, all local stations basically run 24/7. I know WRAL-TV has been running fiber to Time Warner Cable since at least 2001.


> This was many years ago in Indianapolis Comcast Cable would
> pull in WTIU/30 Bloomington, IN (PBS). Most nights when
> WTIU would sign off the St. Louis station on channel 30
> would mysteriously appear. Some nights it was just a blue
> screen, but most nights the St. Louis station would pop in.
>

 

[genXdxerLR]

The Little Rock "locals" (at one time KARK, KATV, KTHV) were microwaved into Berryville, AR beginning about 1989 or so. I remember when KSNJ (then KSNF)and KODE was on the local cable lineup in 1979 (about the time my grandmother started getting cable).

 

[wxctintern]

During the summer of 1997 my family stayed at a cottage in Niantic, Connecticut. The cable company carried Boston's WGBH Channel 2 on Channel 2. It was early Monday Morning and WGBH went off the air for maintainence and WCBS Channel 2 from NYC came in. It was in color and snowy. <P ID="signature">______________
~Jay Clark~
</P>

 

[TimL]

> During the summer of 1997 my family stayed at a cottage in
> Niantic, Connecticut. The cable company carried Boston's
> WGBH Channel 2 on Channel 2. It was early Monday Morning and
> WGBH went off the air for maintainence and WCBS Channel 2
> from NYC came in. It was in color and snowy.
>


On a couple of occasions I have picked up WKAR-TV PBS 23 for East Lansing, Michigan on Cable position 10 here in Canton, Ohio (Time Warner) when WAKR 23 in Akron, Ohio was off the air.

 

[dampier]

> Time-Warner directly via fiber optic cables.

Time-Warner gets fiber or microwave feeds from most stations here in Rochester too, although being on 8, 10, and 13 VHF reduces DX possibilities in any event. These feeds were very evident during various power issues on the transmitter site, which knocked out the OTA signal but didn't affect the cable subscriber at all.

One low power UPN affiliate WBGT-LP in Rochester on Channel 40 was added to TW's lineup after much effort, and it was patently obvious that was an OTA signal which looked like it was picked up by some Radio Shack equipment. Absolutely horrible video and an incredibly annoying 60hz hum on top of the audio. And WBGT paid for the position on the cable dial....

Back in the olden days pre-syndex we did see Syracuse, Buffalo, and an Ottawa CTV affiliate relay from OTA signals. On bad days, 3 from Syracuse would be very snowy and 7 from Buffalo had lots of horizontal lines. Six always had to cope with FM crud because the primary transmitter site for FMers was in the same direction as the antenna pointed north.

 

[RMarino]

> On a couple of occasions I have picked up WKAR-TV PBS 23 for
> East Lansing, Michigan on Cable position 10 here in Canton,
> Ohio (Time Warner) when WAKR 23 in Akron, Ohio was off the
> air.

Back in the '80s on our cable system, when local PBS WEDU Channel 3 in Tampa would sign-off (or early morning before sign-on) we would sometimes get a snowy channel 3 from Savannah, GA!

 

[Lee_T]

One night a few years back when the SRC French CBC channel
used to sign-off on channel 13 and on cable 12, I had received
CKCO-TV out of Kitchener, Ontario with an unID floating
underneath it was snowy and had thin horizontal lines going
across the screen from top to bottom. It was like watching
cable 12 without cable! but when I checked channel 12 on
my other TV that was hooked up with an outdoor aerial there
was nothing much but sometimes WJRT-TV ABC 12 out of Flint,
Michigan with a semi-local and another. I also checked 13
there wasn't much either.

Back when I had cable TV up until we switched to Satellite
in 2001, I used to receive E-Skip interference through
channels 2-6 right on cable.

Has anyone ever experienced e-skip interference on Satellite?
say when your satellite is hooked up to a TV set that is
posisoned on channel 3?

How about the satellite television stations, has anyone
received e-skip or tropo interference from the origional
channels that have their signals on satellite?

I'd be very interested to know.

Take care,

From Lee
-Near Sudbury, Ontario, Canada.

> > On a couple of occasions I have picked up WKAR-TV PBS 23
> for
> > East Lansing, Michigan on Cable position 10 here in
> Canton,
> > Ohio (Time Warner) when WAKR 23 in Akron, Ohio was off
> the
> > air.
>
> Back in the '80s on our cable system, when local PBS WEDU
> Channel 3 in Tampa would sign-off (or early morning before
> sign-on) we would sometimes get a snowy channel 3 from
> Savannah, GA!
>