Some antenna information for OTA HDTV

I had a strange problem where one HDTV station was breaking up or not coming
in at all at certain times. It's UHF Channel 30.1 in Fresno, California (an
ABC affiliate station). Now note that it is supposed to be a UHF station.
I called the station engineer and found that they were actually broadcasting
on VHF channel 9, but something in their signal tells the TV tuner that it
is UHF Channel 30.1. It is important information that would explain why
some people were having reception problems. He said I needed a UHF-VHF
antenna to receive Channel 30.1 and the normal UHF stations. I had a
stacked UHF butterfly antenna on my roof and could not find a cheap VHF-UHF
antenna in our local Radio Shacks, so I glued up some pvc pipe, taped a
folded dipole antenna to it, mounted it on the same roof top mast as the
other antenna, and connected the two thru an antenna splitter/combiner.
Works GREAT and cost less than $8.

For your information, a folded dipole for Channel TV 9 can be made with
ordinary flat 300 ohm TV line. The line needs to be cut at 29.75 inches,
both ends stripped and soldered together. The bottom half of the flat wire
is cut in the middle to connect the feed line to the splitter/combiner (I
used an impedance transformer to convert 300 ohms to 75 ohms to connect to
my shielded cable feed line to my TV) (Radio Shack about $5).

See http://www.wfu.edu/~matthews/misc/dipole.html for an example. You will
need to cut your antenna to a length specific to the channel you want.

I was tempted to add a reflector and director to the dipole antenna, but it
would really be overkill in my circumstance.

If you are having some reception problems, you might find it profitable to
call the station and ask to speak with the station engineer. I went from
crumby reception to great reception after I knew what the problem was.

Sam

Sam wrote:
I had a strange problem where one HDTV station was breaking up or not coming
in at all at certain times. It's UHF Channel 30.1 in Fresno, California (an
ABC affiliate station). Now note that it is supposed to be a UHF station.
I called the station engineer and found that they were actually broadcasting
on VHF channel 9, but something in their signal tells the TV tuner that it
is UHF Channel 30.1. It is important information that would explain why
some people were having reception problems. He said I needed a UHF-VHF
antenna to receive Channel 30.1 and the normal UHF stations. I had a
stacked UHF butterfly antenna on my roof and could not find a cheap VHF-UHF
antenna in our local Radio Shacks, so I glued up some pvc pipe, taped a
folded dipole antenna to it, mounted it on the same roof top mast as the
other antenna, and connected the two thru an antenna splitter/combiner.
Works GREAT and cost less than $8.

For your information, a folded dipole for Channel TV 9 can be made with
ordinary flat 300 ohm TV line. The line needs to be cut at 29.75 inches,
both ends stripped and soldered together. The bottom half of the flat wire
is cut in the middle to connect the feed line to the splitter/combiner (I
used an impedance transformer to convert 300 ohms to 75 ohms to connect to
my shielded cable feed line to my TV) (Radio Shack about $5).

See http://www.wfu.edu/~matthews/misc/dipole.html for an example. You will
need to cut your antenna to a length specific to the channel you want.

I was tempted to add a reflector and director to the dipole antenna, but it
would really be overkill in my circumstance.

If you are having some reception problems, you might find it profitable to
call the station and ask to speak with the station engineer. I went from
crumby reception to great reception after I knew what the problem was.

Sam

Good job! But there are many sources for finding out the actual
digital broadcast channel for a station. You can look the station up on
Wikipedia using the call letters which usually lists the analog and
digital channel. A quick search turns up that you are writing about
KFSN-DT ABC 30 (http://en.wikipedia.org/wiki/KFSN). Plugging your zip
code into antennaweb.org and adding 200' or 300' for antenna height
should give you a list of the digital stations and their broadcast
channel (under the Frequency Assignment column).

You can also look up the station call letters at the FCC database
(http://www.fcc.gov/mb/video/tvq.html) and get the analog and digital DT
entries although this site may be rather technical for some. I looked up
the FCC list for the post analog shutdown digital channel assignments
(tentative combined 1st and 2nd round list can be found at
http://www.fcc.gov/dtv/ under May 23, 2006 entry) for the Fresno
stations. KFSN-DT ABC 30 will be switching it's digital channel to UHF
30 but KAIL-DT My 53 will stay on VHF 7. So if you are getting the
KAIL-DT My 53 station, keep that dipole!

I hope you don't find this reply too much of an info dump, but you are
not alone in getting confused by stations broadcasting their digital
signal on a different channel band - VHF low 2 to 6, VHF high 7 to 13,
and UHF 14 to 69 - than their analog channel that they know the station
by. I hope that by posting these information resources that it may help
out a few people who need to figure out what channels and at what power
their digital local stations are currently at.

Alan F

"Alan F" wrote in message
news:[email protected]
Sam wrote:
I had a strange problem where one HDTV station was breaking up or not
coming
in at all at certain times. It's UHF Channel 30.1 in Fresno, California
(an
ABC affiliate station). Now note that it is supposed to be a UHF
station.
I called the station engineer and found that they were actually
broadcasting
on VHF channel 9, but something in their signal tells the TV tuner that
it
is UHF Channel 30.1. It is important information that would explain why
some people were having reception problems. He said I needed a UHF-VHF
antenna to receive Channel 30.1 and the normal UHF stations.

Sam

Good job! But there are many sources for finding out the actual
digital broadcast channel for a station. You can look the station up on
Wikipedia using the call letters which usually lists the analog and
digital channel. A quick search turns up that you are writing about
KFSN-DT ABC 30 (http://en.wikipedia.org/wiki/KFSN). Plugging your zip
code into antennaweb.org and adding 200' or 300' for antenna height
should give you a list of the digital stations and their broadcast
channel (under the Frequency Assignment column).

You can also look up the station call letters at the FCC database
(http://www.fcc.gov/mb/video/tvq.html) and get the analog and digital DT
entries although this site may be rather technical for some. I looked up
the FCC list for the post analog shutdown digital channel assignments
(tentative combined 1st and 2nd round list can be found at
http://www.fcc.gov/dtv/ under May 23, 2006 entry) for the Fresno
stations. KFSN-DT ABC 30 will be switching it's digital channel to UHF
30 but KAIL-DT My 53 will stay on VHF 7. So if you are getting the
KAIL-DT My 53 station, keep that dipole!

I hope you don't find this reply too much of an info dump, but you are
not alone in getting confused by stations broadcasting their digital
signal on a different channel band - VHF low 2 to 6, VHF high 7 to 13,
and UHF 14 to 69 - than their analog channel that they know the station
by. I hope that by posting these information resources that it may help
out a few people who need to figure out what channels and at what power
their digital local stations are currently at.

Alan F

Alan, the more information, the better. Personally I did not know that
so-called UHF stations broadcast on the VHF frequencies until speaking with
the station engineer. Now that I know this to be fact, I will certainly use
those references you cited to check other stations if I have a problem. I
know there are many more stations in the Fresno area, but unless one is into
religion, Spanish, Asian, Portuguese, etc. programming, I have too many
choices already on account of OTA and DirectTV Satellite.

Sam

Sam,

I have snow on channel 2 and channel 26. All the other channels
are fine.

Can you give me the dimensions I need for those two channels so I can
build me 2 antennas to join with my store bought one?

Duffaukid,
DK



On Wed, 23 May 2007 23:50:15 GMT, "Sam" wrote:


"Alan F" wrote in message
news:[email protected]
Sam wrote:
I had a strange problem where one HDTV station was breaking up or not
coming
in at all at certain times. It's UHF Channel 30.1 in Fresno, California
(an
ABC affiliate station). Now note that it is supposed to be a UHF
station.
I called the station engineer and found that they were actually
broadcasting
on VHF channel 9, but something in their signal tells the TV tuner that
it
is UHF Channel 30.1. It is important information that would explain why
some people were having reception problems. He said I needed a UHF-VHF
antenna to receive Channel 30.1 and the normal UHF stations.

Sam

Good job! But there are many sources for finding out the actual
digital broadcast channel for a station. You can look the station up on
Wikipedia using the call letters which usually lists the analog and
digital channel. A quick search turns up that you are writing about
KFSN-DT ABC 30 (http://en.wikipedia.org/wiki/KFSN). Plugging your zip
code into antennaweb.org and adding 200' or 300' for antenna height
should give you a list of the digital stations and their broadcast
channel (under the Frequency Assignment column).

You can also look up the station call letters at the FCC database
(http://www.fcc.gov/mb/video/tvq.html) and get the analog and digital DT
entries although this site may be rather technical for some. I looked up
the FCC list for the post analog shutdown digital channel assignments
(tentative combined 1st and 2nd round list can be found at
http://www.fcc.gov/dtv/ under May 23, 2006 entry) for the Fresno
stations. KFSN-DT ABC 30 will be switching it's digital channel to UHF
30 but KAIL-DT My 53 will stay on VHF 7. So if you are getting the
KAIL-DT My 53 station, keep that dipole!

I hope you don't find this reply too much of an info dump, but you are
not alone in getting confused by stations broadcasting their digital
signal on a different channel band - VHF low 2 to 6, VHF high 7 to 13,
and UHF 14 to 69 - than their analog channel that they know the station
by. I hope that by posting these information resources that it may help
out a few people who need to figure out what channels and at what power
their digital local stations are currently at.

Alan F

Alan, the more information, the better. Personally I did not know that
so-called UHF stations broadcast on the VHF frequencies until speaking with
the station engineer. Now that I know this to be fact, I will certainly use
those references you cited to check other stations if I have a problem. I
know there are many more stations in the Fresno area, but unless one is into
religion, Spanish, Asian, Portuguese, etc. programming, I have too many
choices already on account of OTA and DirectTV Satellite.

Sam

On May 23, 6:48 pm, DK wrote:
Sam,

I have snow on channel 2 and channel 26. All the other channels
are fine.

Can you give me the dimensions I need for those two channels so I
can
build me 2 antennas to join with my store bought one?

Duffaukid,
DK

snip

If your signal is so low that there is only 'snow', you'll probably
need more antenna than a simple folded dipole. But if you wish to try
anyway, here is a link to a calculator.

http://www.k7mem.150m.com/Electronic...ed_dipole.html

I recommend using 20 AWG wire in the calculator and set the impedance
value at 300.

Actual DTV channel numbers can be found here in the last column

http://www.nab.org/AM/ASPCode/DTVSta...TVStations.asp

Channel frequencies can be found here

http://www.chem.hawaii.edu/uham/catvfreq.html

A folded dipole up high might do it but you should look into a real
antenna from Channel Master or Winegard if you're living in a house.
Apartments are problems for antennas so the dipole may be your only
chance.

Good luck

GG

G-Squared gave some good references to calculating your own. However, if
you are getting snow, maybe you just need to turn your existing antenna
towards the station. Also, Channel 2 is VHF and Channel 26 is UHF, so maybe
you are better off with a combo UHF-VHF antenna.

In addition to G-Squared references for calculating antenna length, see
http://www.antennaweb.org/aw/welcome.aspx and fill in your address to see
recommended orientation of your antenna (Enable cookies for that site)

Sam

"DK" wrote in message
...

Sam,

I have snow on channel 2 and channel 26. All the other channels
are fine.

Can you give me the dimensions I need for those two channels so I can
build me 2 antennas to join with my store bought one?

Duffaukid,
DK



On Wed, 23 May 2007 23:50:15 GMT, "Sam" wrote:


"Alan F" wrote in message
news:[email protected]
Sam wrote:
I had a strange problem where one HDTV station was breaking up or not
coming
in at all at certain times. It's UHF Channel 30.1 in Fresno,
California
(an
ABC affiliate station). Now note that it is supposed to be a UHF
station.
I called the station engineer and found that they were actually
broadcasting
on VHF channel 9, but something in their signal tells the TV tuner that
it
is UHF Channel 30.1. It is important information that would explain
why
some people were having reception problems. He said I needed a UHF-VHF
antenna to receive Channel 30.1 and the normal UHF stations.

Sam

Good job! But there are many sources for finding out the actual
digital broadcast channel for a station. You can look the station up on
Wikipedia using the call letters which usually lists the analog and
digital channel. A quick search turns up that you are writing about
KFSN-DT ABC 30 (http://en.wikipedia.org/wiki/KFSN). Plugging your zip
code into antennaweb.org and adding 200' or 300' for antenna height
should give you a list of the digital stations and their broadcast
channel (under the Frequency Assignment column).

You can also look up the station call letters at the FCC database
(http://www.fcc.gov/mb/video/tvq.html) and get the analog and digital DT
entries although this site may be rather technical for some. I looked up
the FCC list for the post analog shutdown digital channel assignments
(tentative combined 1st and 2nd round list can be found at
http://www.fcc.gov/dtv/ under May 23, 2006 entry) for the Fresno
stations. KFSN-DT ABC 30 will be switching it's digital channel to UHF
30 but KAIL-DT My 53 will stay on VHF 7. So if you are getting the
KAIL-DT My 53 station, keep that dipole!

I hope you don't find this reply too much of an info dump, but you are
not alone in getting confused by stations broadcasting their digital
signal on a different channel band - VHF low 2 to 6, VHF high 7 to 13,
and UHF 14 to 69 - than their analog channel that they know the station
by. I hope that by posting these information resources that it may help
out a few people who need to figure out what channels and at what power
their digital local stations are currently at.

Alan F

Alan, the more information, the better. Personally I did not know that
so-called UHF stations broadcast on the VHF frequencies until speaking
with
the station engineer. Now that I know this to be fact, I will certainly
use
those references you cited to check other stations if I have a problem. I
know there are many more stations in the Fresno area, but unless one is
into
religion, Spanish, Asian, Portuguese, etc. programming, I have too many
choices already on account of OTA and DirectTV Satellite.

Sam

"Alan F" wrote in message
news:[email protected]

snip

I hope you don't find this reply too much of an info dump,
but you are
not alone in getting confused by stations broadcasting their
digital
signal on a different channel band - VHF low 2 to 6, VHF high
7 to 13,
and UHF 14 to 69 - than their analog channel that they know
the station
by. I hope that by posting these information resources that it
may help
out a few people who need to figure out what channels and at
what power
their digital local stations are currently at.

For those of us who'd rather watch TV than build one (or any
component relevant to its reception) your posts are superb,
Alan.

Some time ago I posted regarding OTA indoor/outdoor antenna and
you replied with very useful info. When an antenna installer
came here to quote a price, he mentioned that I've had an attic
antenna (12 unit single level with utility service in the attic)
installed for more than 40 years - long abandoned by prior
owners for its poor analog reception. Sure enough, I found the
blank plate covering the outlet and tapped in to the twin-lead
to feed my ATSC tuner. I now get 49 channels (perhaps the
wrong nomenclature?) 9 of which are HDTV.

At some time, should I live so long, that 40+ year old twin lead
clinging to the 75 ohm converter by just a few copper-like
threads should be replaced. At the moment, the reception is
incredible.

Turns out that all 7,000 dwellings in this walled community had
attic antennae - probably none has ever gotten decent analog
reception as there are multiple outdoor antennae on every single
building:-(