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Re: OTA TV reception problems
On Sunday, November 6, 2016 at 7:40:38 PM UTC-5, snipped-for-privacy@gmail.com wro
te:
Quoted text here. Click to load it
 holing that this time someone might read it who may have a theory as to wh
at could be going on.  
Quoted text here. Click to load it
 about 60 miles from here. Lately I as well as several other people I know  
have been experiencing intermittent problems with channel four. While most  
other channels are presently operating fine, for the past 10 days or so cha
nnel 4's signal has been in the toilet. This station, WBZ TV operates on UH
F channel 30, runs 825KW, and has an antenna height of 390 meters. By contr
ast Channel 5, WCVB, operates on UHF channel 20, runs 625 KW, and shares th
e same tower and has it's antenna at the same height as channel 4's, and we
 never have any problems with that channel. Could propagation be that much  
different 60 MHZ apart? What is really weird is that the signal just drops  
to almost nothing.  
Quoted text here. Click to load it
planation for this. Does anyone have any theories about this? Thanks, Lenny

Here is some background information from my previous posting: (I was thinki
ng "drive" miles when I said that we were 60 miles from Boston). As the cro
w flies we are about 45. Sorry for that bit of misinformation. The followin
g previous post was when the problem first surfaced.  

     
Sep 21
For the past ten days or so we have been having problems with TV channel 4.
 This station broadcasts on UHF from Boston Mass. and we are about 45 miles
 (as the crow flies) from the transmitter. The antenna is an old, but in go
od condition,  very high gain Channel Master 5 foot parabolic which is moun
ted on a tripod about 6 feet off the roof. There is a mast mounted Winegard
 GA 8780 preamplifier with a 28 DB UHF section along with a very low noise  
figure mounted about 2 feet from the antenna. The cable is RG6 Quad which g
oes into a two way splitter. We have several different receivers, Converter
 boxes) but the one I use for assessment because it shows signal quality as
 well as signal strength is a Channel Master 7001. Our elevation is 410 fee
t and we are surrounded by trees, some deciduous and some pine.

Most of the time, in spite of this not so ideal situation, (location) I can
 receive the three networks and a few independents. The signal display on t
he converter shows, as two horizontal bars, "signal quality" and "signal le
vel". On most channels most of the time signal quality is pegged at 100 per
cent and signal level runs between 45 and 55 percent. Within this window I  
usually have no problems with reception. As long as signal quality doesn't  
fold back I usually will get no drop outs. If it should falter excessively  
though both picture and sound will break up and intermittently freeze. So I
'm pretty familiar with what conditions will produce a good signal.

Lately Channel 4 although displaying 54 percent signal level and 100 percen
t signal quality has had very slight "tearing streaks" going through the pi
cture. If these aberrations only affected the picture we would be able to w
atch the program. However this problem seems to chop up the sound as well.  
This makes it impossible to watch a program.

The weather of late has been hot and humid, which is atypical for New Engla
nd this time of year. I've noticed in the past that during this type of wea
ther we do sometimes lose reception on several channels for a day or two bu
t never this long. I'm just wondering if anyone might have a theory as to w
hat could be happening here. This only seems to affect channel 4, (where al
l our shows happen to be). Thanks, Lenny

I also corresponded with the chief engineer at WBZ and got this back.

Lenny,

  

My apologies for the delay in replying.

  

I don?t have a good answer for why your reception has degraded rece
ntly.  We have not been having any trouble with our transmission systems.

  

Your installation sounds like a good one, though I think it may be a bit ov
erdone, as a high-gain antenna in combination with 28 dB of amplification i
s probably more than you need, even at that distance.  For comparison, I li
ve 43.1 air miles from the transmit antenna, and I use a Channel Master 422
8 8-bay bowtie antenna on the roof of my one-story house, with no amplifica
tion.  I get full-bore signal into the TV on almost all channels.  We have  
had incidences with viewers who had too much amplification in which they lo
st WBZ and WFXT, which had the most powerful signals in the Boston market (
at the time).  They were overdriving their TVs and as a result suffering th
e loss of the two stations they should have received with the least effort.

  

Wish I had a more definitive answer?

  

cid: snipped-for-privacy@01CEC683.AF77500

Robert Yankowitz, CPBE

WBZ-TV WSBK BOSTON

1170 Soldiers Field Road, Boston, MA 02134

Chief Engineer

file:///M:/pmasucc/Work/General%20Info/email-combo%20logos.jpg

o 617 562-5044

c 617 828-1041

f 617 787-7106

www.cbsboston.com

Then I replied back:

Lenny I wish I had answer for why your reception has degraded recently.  We
 have not been having any trouble with our transmission systems.

  

Your installation sounds like a good one, though I think it may be a bit ov
erdone, as a high-gain antenna in combination with 28 dB of amplification i
s probably more than you need, even at that distance.  For comparison, I li
ve 43.1 air miles from the transmit antenna, and I use a Channel Master 422
8 8-bay bowtie antenna on the roof of my one-story house, with no amplifica
tion.  I get full-bore signal into the TV on almost all channels.  We have  
had incidences with viewers who had too much amplification in which they lo
st WBZ and WFXT, which had the most powerful signals in the Boston market (
at the time).  They were overdriving their TVs and as a result suffering th
e loss of the two stations they should have received with the least effort.

  

Wish I had a more definitive answer?

  

cid: snipped-for-privacy@01CEC683.AF77500

Robert Yankowitz, CPBE

WBZ-TV WSBK BOSTON

1170 Soldiers Field Road, Boston, MA 02134

Chief Engineer

file:///M:/pmasucc/Work/General%20Info/email-combo%20logos.jpg

o 617 562-5044

c 617 828-1041

f 617 787-7106

www.cbsboston.com

snipped-for-privacy@cbs.com

-------- Original message --------
Date: 9/21/16 11:00 PM (GMT-05:00)
snipped-for-privacy@boston.cbs.com>
Subject: General Information - Boston - [#95913]

Name *
    

Leonard Stein

Email *
    

snipped-for-privacy@gmail.com

Phone Number *
    

(603) 887-4253

Direct Your Message To CBS Local Staff In... *
    

Boston

Link (if appropriate)
    

Please forwaed this to engineering dept.

Comment

For the past ten days or so we have been having problems with TV channel 4.
 We are located in Chester N.H. about 45 miles (as the crow flies) from the
 transmitter. The antenna is an old, but in good condition, very high gain  
Channel Master 5 foot parabolic which is mounted on a tripod about 6 feet o
ff the roof. There is a mast mounted Winegard GA 8780 preamplifier with a 2
8 DB UHF section along with a very low noise figure mounted about 2 feet fr
om the antenna. The cable is RG6 Quad which goes into a two way splitter. T
he receiver, (converter box) is a Channel Master 7001. Our elevation is 410
 feet and we are surrounded by trees, some deciduous and some pine.

Most of the time, in spite of this not so ideal situation, (location) I can
 receive the three networks and a few independents. The signal display on t
he converter shows, as two horizontal bars, "signal quality" and "signal le
vel". On most channels most of the time signal quality is pegged at 100 per
cent and signal level runs between 45 and 55 percent. Within this window I  
usually have no problems with reception. As long as signal quality doesn't  
fold back I usually will get no drop outs. If it should falter excessively  
though both picture and sound will break up and intermittently freeze. So I
'm pretty familiar with what conditions will produce a good signal.

Lately Channel 4 although displaying 54 percent signal level and 100 percen
t signal quality has had very slight "tearing streaks" going through the pi
cture. If these aberrations only affected the picture we would be able to w
atch the program. However this problem seems to chop up the sound as well.  
This makes it impossible to watch a program. I am a TV repair technician an
d I have never seen this type of choppy sound on either OTA or cable before
.

The weather of late has been hot and humid, which is atypical for New Engla
nd this time of year. I've noticed in the past that during this type of wea
ther we do sometimes lose reception on several channels for a day or two bu
t never this long. I'm just wondering if anyone there might have a theory a
s to what could be happening here. This only seems to affect channel 4, (wh
ere all our shows happen to be). Thanks, Lenny

  
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 at 3:55 PM
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Hi Robert

Thank you for getting back to me. One thing that I failed to mention
is that this is not a new installation. We put this antenna up about
three years ago and it has always seemed to perform well.

I hear what you are saying about overload, and in theory Chester NH is
not such a haul from Boston. TV Fool never mentions the use of an
amplifier for my location relating to Boston, and I have used that
resource a lot to determine whether an antenna job at a certain
location would be feasible or not. The preamp though has always seemed
to make  a substantial difference here as well as throughout town. I
had a customer years ago who lived out of town near the top of the
mountain that is partially blocking our South West view. He was
watching everything from Boston including 10 and 12 from Providence,
with rabbit ears. So I've always figured that it must be the foliage
and the terrain that's attenuating my signal.

Before digital,  for my own house I used separate VHF and UHF
antennas. We never needed any help with VHF, but UHF was always a
challenge for us. The UHF antenna at the time was an 8 bay. During
this period  Winegard had just come out with a commercial preamp that
had slightly lower gain but boasted an unheard of  1DB noise figure. I
had to try this so I ordered one and installed it after the 8 bay. I
pointed it towards Boston but channel 50's transmitter in Hudson NH
splattered across the entire band. Although having a very hot front
end the commercial preamp was not nearly as forgiving of overloads as
the 8780. I eventually put a 20 DB trap set for channel 50 in line and
that solved the overload problem. However in spite of all this, UHF
reception with the 8 bay from Boston was never really very good at our
house.

Since as we all know it's not possible to watch a polar bear in a snow
 storm with digital three years ago I realized that I had to do
something. This parabolic which I'm presently using is a 300 ohm
antenna which I had liberated from a job about 20 some odd years ago.
I had always planned to use it "some day" and it had been sitting in
the woods behind my house since. It had a few broken reflectors which
I repaired.I looked up the specs recently on this antenna and it seems
to beat everything out there. Gain is between 13 to 16 DB, but it's
narrow beam width is really where it excels. Early on I had considered
that my problem could possibly be multipath, however just turning this
antenna a few degrees and signal starts to drop like a rock.

We didn't have cable TV here in Chester until the early 1990's, and
back then I used to install quite a few antennas and retrofit existing
ones with preamps. I had a nice Sadelco signal meter that tuned up to
channel 83. I no longer do antenna work so I don't presently have
equipment to measure OTA signals. So now admittedly a lot of this is
an educated guess. Back then most consumer equipment particularly
antennas were 300 ohms, and since the GA8780's input impedance also
was 300 ohms  I kind of standardized on this amp for my retrofits as
well as new installations. The noise figure was about 3 DB which was
the best of the time, beating Channel Master's figure of 5. However
the real attraction of this amp was the very forgiving limiter
circuit. I never had one overload on me, including those used in
installations much higher than mine.

So as you might imagine I've been very frustrated with this problem.
However as of five days ago the problem has disappeared. Signal levels
and quality as measured on my converter boxes show no difference, and
if this was weather related we have had varying degrees of weather
through this period as well. We do sometimes experience days at a time
where reception is poor for whatever reason but it's always reflected
on the signal strength and quality indication on the converter box
meter. This was definitely not the case this time though. To the best
of my recollection in this past three years this particular type of
problem has never happened before.

I do have a theory though that I wanted to suggest. The orientation of
my antenna when it is optimized for Boston puts it a few degrees South
East of New York City. Do you think that skip conditions were such
through this period of time that this could possibly have been CO
channel interference from WNBC in New York? As I had previously
mentioned no other channels were affected nor have I noticed anything
unusual on any of the Amateur frequencies or my low band two way
business radio system.

We do occasionally see what I believe must be tropospheric inversion,
and we do seem to experience them at different times of the year.
During these periods, which typically last up to five days, Boston UHF
TV stations that I never can pull in such as 56 and 68 come bombing
in, and many times with 90 percent signal strength. Then as
mysteriously as they appeared, after a period of time they're gone.
This episode however didn't seem to be an inversion, as there were no
newcomers in my channel line up through this time.

In 1975 I decided that I wanted to work in broadcasting. I got my
First and I was hired as a studio technician for a UHF TV station in
Central New York. Much of that work involved translator maintenance. I
still recall (although not fondly) those awful cold trips up the
mountains when the snowmobile wasn't running to service those
miserable things. After that stint I switched careers to military, and
then industrial electronics. I took a hard look at my life after that
and since I had been repairing TV's from the time I was a teenager I
decided to go in for myself. So since 1983 I've operated my own
consumer electronics service business. Now I'm semi retired, (whatever
that means) and I haven't seen the inside of a TV studio no less a
network studio in 45 years. I'm sure much has changed.

I'm sure that you are more than familiar with it than I but I found a
rather interesting article on tropospheric propagation on Wikipedia,
and there was also if you are interested some propaganda on my
antenna.

Thank you very much for trying to help me evaluate this problem. I
appreciate the time and trouble you've taken.
Very truly yours, Lenny Stein, KC1CPX

https://en.wikipedia.org/wiki/Tropospheric_propagation

http://www.rocketroberts.com/cm4251/cm4251.htm
snipped-for-privacy@cbs.com
I wanted to include all the background information before this thread began
. Lenny

BTW, here are my coordinates: and although the topo maps said different acc
ording to Google my altitude is 115 meters
 465 Derry Rd, Chester, NH 03036, USA
Latitude: 42.930838 | Longitude: -71.281921

Re: OTA TV reception problems
Quoted text here. Click to load it

More than likely because you're posting from google groups.

    * Killfiling google & XXXXbanter.com: jonz.net/ng.htm

Re: OTA TV reception problems
On Tue, 8 Nov 2016 13:56:36 -0800 (PST), snipped-for-privacy@gmail.com
wrote:

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(...)
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I can see why you received no response.  357 lines of disorganized
ranting is difficult to parse.  Please get organized and save readers
the effort of wading through your mess.  Same as always:
1.  What problem are you trying to solve?  Keep it very simple.
2.  What equipment do are you using?  Numbers and details are good.
3.  What have you done so far and what happened?

I'm busy for a few days and will hopefully do a path profile this
weekend.  I don't know if I can squeeze much out of the path analysis
except that you might have some obstructions or Fresnel zone
diffraction problems.   From the plots I previously posted, the
coverage of both stations look identical.  

Did you do any of the substitution tests that I recommended?  The best
test would be just the TV, a length of RG-6/u, and a simple 1/2 wave
(at 500MHz) dipole hund outside the window.  No amps or splitters.

Did you run your address through TVfool.com to see what signal levels
they predict?

Quoted text here. Click to load it

Slight misunderstanding.  I need the type of antenna you are using at
your house, and its elevation above ground level.  You can save me
some trouble excavating the information from your archive by listing
everything (inclusive) between the antenna and the TV receiver.  

Quoted text here. Click to load it

Thanks for using a decent (decimal degrees) format.  I hate DMS.


but in NAD27.  Converting the FCC DMS to decimal and datum into WGS84:
(42.310278 N, -71.237222W) NAD27 -> (42.31025 N, 71.23669 W) WGS84.
Antenna height above ground 387 meters (1270 ft).
Nice little monster tower:
<http://www.necrat.us/bztower.html

Well, I have a few minutes I'll throw together a Google Earth path
profile.  It won't be very accurate and won't show Freznel zones, but
will show any obstructions.  Looks like drawing a 1270ft tower is
gonna be difficult, so I guessed:
<
http://802.11junk.com/jeffl/coverage/KBCZ-WBZ/WBZ-Lenny.jpg

If you have Google Earth, here's the PRELIMINARY KMZ file:
<http://802.11junk.com/jeffl/coverage/KBCZ-WBZ/WBZ%20path.kmz
Looks like you have a rather large hill directly in the path and very
close to you.  A 150ft or so tower at your end would be needed to
clear the hill.


Incidentally, I vaguely recall a similar OTA problem where one channel
was uncharacteristically low in receive signal.  It turned out to be
an unterminated length of coax on a coaxial splitter.  Even though the
splitter was suppose to have perhaps 20dB(?) of isolation between
ports, the device was so badly built that I'm sure it was much less.  
<
http://802.11junk.com/jeffl/crud/CATV-splitters.jpg

The unterminated length acted as a notch filter which just happened to
land on the TV channel frequency.  Replacing the spllitter and
removing the coax or terminating it with 75 ohms solved the problem.

--  
Jeff Liebermann     snipped-for-privacy@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
We've slightly trimmed the long signature. Click to see the full one.
Re: OTA TV reception problems
On 11/10/2016 11:28 AM, Jeff Liebermann wrote:
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  I would try what the station engineer pointed out.
You have a high gain antenna and a 28db amplifier, try it without the
amp.
  I'm 51.9 miles* from a digital channel 36, I cut a folded dipole using
300 ohm twin lead, as I recall about 9.5" long.  No Amp. It is no more  
than 10ft off the ground. I have zero dropouts and no audio problems.

WTVY
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Opps, just saw a glitch go by in the video.

                                        Mikek


*According to TVfool.


OTA TV reception problems
captainvideo:

Your problem is two-fold: distance, and  
the all-digital broadcast requirement.


8 years ago, on NTSC(analog), distance
would not have been been such an issue.
You probably would have had snow on  
a lot of channels, but you still had picture  
and sound.


Now, on ATSC(digital), you don't get certain
stations at all, and frequent dropouts on
others.

This is why I maintain that ATSC is 'less
Green' than NTSC was:  While with  
digital stations can piggy-back channels
(4.2, 4.3, 4.4, etc.)  they must BOOST  
THEIR SIGNAL for people with same  
OTA setup to receive them in the first  
place.  And increasing signal strength  
meansUSING MORE ENERGY - something
the folks over at Alt.Video.Digital.Tv fail  
to grasp.

You said you are using a 'parabolic' antenna
currently - I'm assuming that is dish-shaped.

Have you looked into a variation on this  
form factor yet?  It's all I'll ever use, even
just 35 miles away from my market:

https://m.lowes.com/pd/Channel-Master-Outdoor-Non-Amplified-Yagi-Type-Anten
na/50005786?cm_mmc=SCE_PLA_ONLY-_-RoughPlumbingElectrical-_-SosHomeAutoma
tion-Communication-_-50005786:Channel_Master&CAWELAID=&kpid50%005786&CA
GPSPN=pla&k_clickID35%fefdd1-395a-47bd-a160-f2260ea5c961


Re: OTA TV reception problems
On Tue, 15 Nov 2016 04:10:07 -0800 (PST), snipped-for-privacy@gmail.com
wrote:

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You may fail to grasp it, too.  When you hear about TV stations
(especially UHF stations) using millions of watts of power, they are
referring to ERP - Effective Radiated Power.  That means the actual
power going into the antenna is much lower but the antenna has very
high gain.  Rarely do stations use more than a few thousand watts of
actual power.  The transmitter's actual power usage is a drop in the
bucket compared to all the other energy a TV station uses for lights,
cameras, HVAC, etc.  

Re: OTA TV reception problems
Pat wrote: "You may fail to grasp it, too.  When you hear about TV stations  
(especially UHF stations) using millions of watts of power, they are  
referring to ERP - Effective Radiated Power.  That means the actual  
power going into the antenna is much lower but the antenna has very  
high gain.  Rarely do stations use more than a few thousand watts of  
actual power.  The transmitter's actual power usage is a drop in the  
bucket compared to all the other energy a TV station uses for lights,  
cameras, HVAC, etc.   "

________
Alright, say a typical medium market  
station has historically transmitted  
2,000W as a NTSC.  2009 they go  
fully ATSC, still at 2,000W.  Hundreds  
of letters from viewers flood their  
mailbox, and thousands of callers  
jam their phone boards about not  
being able to pick them up over the  
air with their new TVs.  Most are from  
viewers in the outer one-third of the  
station's transmission radius.


Station board deliberates, and  
after a couple months decides to  
increase transmitter wattage to 2,500W.
Viewer complaints plummet, while  
greenhouse gas emmissions steadily  
rise to generate additional electricity as  
this scenario is mulitiplied across dozens  
of medium markets and many major  
markets.

Grasp that!


Yeah, I get that actual wattage is but  
a fraction of ERP, but it still adds up
as many TV stations must increase their  
signal strength to cover the same  
audience area in digital as they did  
via analog.

Re: OTA TV reception problems
On Tue, 15 Nov 2016 08:31:32 -0800 (PST), snipped-for-privacy@gmail.com
wrote:

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Don't forget the part where they have to modify their license at the
FCC after hiring engineers to show that the increased power doesn't
cause interference with any other licensed station in the area (or in
Canada).  That process can takes a long time and is expensive even
before equipment is purchased.  Most of the applications are on hold
right now waiting for the auctions to be complete.  ATSC has lots of
issues, but creating a significant increase in greenhouse gases isn't
one of them.
  
Quoted text here. Click to load it

Re: OTA TV reception problems
Pat wrote:
Quoted text here. Click to load it


    I was an engineer at an analog UHF station with a 5 MW  EIRP, on a  
1700' tower.  The Comark transmitter used a pair of 65 KW EEV Klystons,  
for 130 KW of RF into the diplexer. A third 65 KW Klystron was used for  
the aural signal. That was in the late '80s, and our electric bill for  
the transmitter site was $45,00 a month.

    Solid state transmitters are modular, with around 1KW output, per  
tray. Look at the Harris Broadcast website for some actual data.


--  
Never piss off an Engineer!

They don't get mad.

We've slightly trimmed the long signature. Click to see the full one.
Re: OTA TV reception problems
On 18/11/16 13:44, Michael A. Terrell wrote:
Quoted text here. Click to load it

I have a half-dozen such modules here, unfortunately
with the water-cooled heatsink removed, if you want
photos or to ask any questions. The modules are single
or dual, using a BLF278 dual FET each. A 30W input is
split into six to drive three duals, which are then
combined to produce about 1KW from about 6KW input at
50V. The power supply rectifies three-phase 415V mains
and chopped it to produce 50V at 60A, scary.

A local ATV transmitter was using more than 50 of these
to put 50KW up the spout. Pretty old-tech now though,
the new lateral MOSFETs from NXP produce 1500W from a
single device (two FETs), as Michael T has pointed out
recently.

The really interesting bit to me is how simple the baluns
are - just a couple of 8cm lengths of special hardline
to match from about 12 ohms up to 50, at 225MHz.
Transmission line transformers FTW! There's quite a few
reference designs for this class of transmitter at
http://nxp.com

Clifford Heath.

Re: OTA TV reception problems
Clifford, Michael:

So you're saying modern ATSC transmitters  
actually use less power then the old NTs?

Re: OTA TV reception problems
snipped-for-privacy@gmail.com wrote:
Quoted text here. Click to load it


The heaters in Klystons used a lot of power, that had to be removed as  
heat, in a water chiller. One 25 KW UHF transmitter that I rebuilt used  
a pair of 1.5V, 1000A heaters per tube.  That was 3 KW, then the fan on  
the water chiller was a 480V, three phase, 5 hp motor.  The circulating  
pump was anther two HP.  None of this ended up at the output port.


--  
Never piss off an Engineer!

They don't get mad.

We've slightly trimmed the long signature. Click to see the full one.
Re: OTA TV reception problems
Michael Terrell wrote: - hide quoted text -
snipped-for-privacy@gmail.com wrote:  
Quoted text here. Click to load it


"The heaters in Klystons used a lot of power, that had to be removed as  
heat, in a water chiller. One 25 KW UHF transmitter that I rebuilt used  
a pair of 1.5V, 1000A heaters per tube.  That was 3 KW, then the fan on  
the water chiller was a 480V, three phase, 5 hp motor.  The circulating  
pump was anther two HP.  None of this ended up at the output port. "
- show quoted text -


That doesn't answer my question of whether  
or not AT transmitters use less power than  
NT.  Just a simple Yes or No would suffice.

Re: OTA TV reception problems
On Saturday, November 19, 2016 at 2:52:21 AM UTC-5, snipped-for-privacy@gmail.com wrote:
Quoted text here. Click to load it

there is not a simple answer..

if the station stayed on the same frequency, then it can use lower power digital compared to analog.  Digital fundamentally requires less power to close the link.

HOWEVER.

many stations also switched from a VHF frequency to a UHF frequency.
The FCC allows more power to be used on UHF.  

So in each case the answer is ...it depends.

I think it would be a gross exaggeration to say that digital TV is environmentally  more friendly compared to analog because of power consumption.

m


Re: OTA TV reception problems
snipped-for-privacy@yahoo.com says...
Quoted text here. Click to load it



There is another factor also.  For the same bandwidth there can be  
several low resolution TV 'chanels' on the same ammount of bandwidth as  
one analog tv chanel.


Re: OTA TV reception problems
On Sun, 6 Nov 2016 16:40:35 -0800 (PST), snipped-for-privacy@gmail.com
wrote:
(...)

This is too easy.
WBZ has been running on reduced power for most of the last few weeks
thanks to an antenna problem:
<http://boston.cbslocal.com/2016/11/07/wbz-tv-wsbk-tv-operating-at-reduced-power/
<http://boston.cbslocal.com/2016/10/22/transmission-issue-causes-outage-for-some-wbz-tv-viewers/
No clue if it has been fixed, but judging by the lack of updates,
probably not.

--  
Jeff Liebermann     snipped-for-privacy@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
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Re: OTA TV reception problems
On 11/15/2016 11:09 AM, Jeff Liebermann wrote:
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  Well that takes all the fun out of it!
  But do note my post of good reception at 51.9m miles with
cut to length folded dipole, 10 ft off the ground.
Channel 36, about 9.5" long.
                             Mikek


Re: OTA TV reception problems

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Occam's Razor.


Sure, it can be done at 45 miles depending on tx power and frequency.
However, Captain Video has an additional problem in the form of a
mound of dirt in between his antenna and the station transmitter.  
<
http://802.11junk.com/jeffl/coverage/KBCZ-WBZ/WBZ-Lenny.jpg

or if you have Google Earth handy:
<http://802.11junk.com/jeffl/coverage/KBCZ-WBZ/WBZ%20path.kmz
The above path profile is NOT very accurate.  I stopped working on the
problem after Captain Video disappeared from the thread.

Incidentally, I sometimes can watch KMPH TV from Fresno, CA which is
about 200 miles away from Ben Lomond.  I live on the side of a hill
which helps.  The real culprit is atmosheric ducting and edge
diffraction from two mountain ranges in between.  It only happens a
few days per year, usually in the summer, but the picture is 100%
perfect.


--  
Jeff Liebermann     snipped-for-privacy@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
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Re: OTA TV reception problems
On 11/18/2016 5:02 PM, Jeff Liebermann wrote:
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  When I was a lot younger living in Kalamazoo Michigan, late one night
I received a Wisconsin TV station across lake Michigan.

                              Mikek

Re: OTA TV reception problems
On 11/15/2016 12:09 PM, Jeff Liebermann wrote:
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The problem (defective transmission line to the upper master antenna on  
the CBS tower in Needham) was finally fully resolved this morning at  
4:55AM. Lots more details at
http://www.wgbh.org/about/Tower_and_Transmission_Signal_Issues.cfm
(The CBS tower carries virtual channels 2, 4, 5, 8, 38, 44, and 48.)

Tony Matt


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