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Alt 18.09.2008, 11:44   #1
K. B.
 
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RCA Antenna Guide

<http://www.staytuned2tv.com/>

Kirk Bayne
alt.video.digital-tv Home Page
<http://www.geocities.com/lislislislis/avdtv.htm>
 
Alt 24.09.2008, 06:36   #2
numeric
 
Beiträge: n/a
Re: RCA Antenna Guide


"K. B." <hotmail.com@lis2lis2> wrote in message
news:km84d41pv6msnf3uh1nme1j7kkafnn8gif@4ax.com...
> <http://www.staytuned2tv.com/>
>


"Digital signals are different from regular, analog TV signals. They require
precise directional reception to give you consistent performance."

This is just the opposite of my experience. In-fact it is far easier to
receive digital signals from multiple directions than analog channels
without adjusting the antenna. Digital TV is crystal clear while the off
axis analog channels are plagued with ghosts and noise. I get digital TV
from two cities using a single directional antenna aimed at the more distant
city. The cities are about 134 degrees apart from my location.


 
Alt 24.09.2008, 09:35   #3
Sal M. Onella
 
Beiträge: n/a
Re: RCA Antenna Guide


"numeric" <numeric@att.net> wrote in message
newstjCk.236301$102.180380@bgtnsc05-news.ops.worldnet.att.net...
>
> "K. B." <hotmail.com@lis2lis2> wrote in message
> news:km84d41pv6msnf3uh1nme1j7kkafnn8gif@4ax.com...
> > <http://www.staytuned2tv.com/>
> >

>
> "Digital signals are different from regular, analog TV signals. They

require
> precise directional reception to give you consistent performance."
>
> This is just the opposite of my experience. In-fact it is far easier to
> receive digital signals from multiple directions than analog channels
> without adjusting the antenna. Digital TV is crystal clear while the off
> axis analog channels are plagued with ghosts and noise. I get digital TV
> from two cities using a single directional antenna aimed at the more

distant
> city. The cities are about 134 degrees apart from my location.


Agree. My usual configuration uses a roof antenna aimed north toward Los
Angeles from the south part of San Diego County, about seven miles north of
the Mexican border.

That one antenna gets me LA stations (usually -- some weather conditions can
mess it up), as well as all the San Diego and Mexican digitals with only
rare exceptions.

It's not a sophisticated antenna. It's literally the UHF elements off an
old all-channel antenna that fell off my neighbor's roof and got damaged. I
hacksawed through the boom, separating the UHF and VHF portions, connected a
balun to the UHF elements, stuck the thing up on a pole and ran coax down to
the TV.

This is not rocket science, requiring long periods of intense study to
master. Most people will be able to get digital TV to work as long as they
don't wait for the equipment to climb out of the carton and install itself..


 
Alt 24.09.2008, 20:18   #4
UCLAN
 
Beiträge: n/a
Re: RCA Antenna Guide

Sal M. Onella wrote:

> Agree. My usual configuration uses a roof antenna aimed north toward Los
> Angeles from the south part of San Diego County, about seven miles north of
> the Mexican border.
>
> That one antenna gets me LA stations (usually -- some weather conditions can
> mess it up), as well as all the San Diego and Mexican digitals with only
> rare exceptions.
>
> It's not a sophisticated antenna. It's literally the UHF elements off an
> old all-channel antenna that fell off my neighbor's roof and got damaged. I
> hacksawed through the boom, separating the UHF and VHF portions, connected a
> balun to the UHF elements, stuck the thing up on a pole and ran coax down to
> the TV.
>
> This is not rocket science, requiring long periods of intense study to
> master. Most people will be able to get digital TV to work as long as they
> don't wait for the equipment to climb out of the carton and install itself..


I get the Mt. Wilson UHF digital stations with a CM4228 antenna mounted INSIDE
in a north facing window from North County.
 
Alt 25.09.2008, 08:29   #5
Sal M. Onella
 
Beiträge: n/a
Re: RCA Antenna Guide


"UCLAN" <nomail@thanks.org> wrote in message
news:NvvCk.15604$Il.6119@newsfe09.iad...
> Sal M. Onella wrote:



> > This is not rocket science, requiring long periods of intense study to
> > master. Most people will be able to get digital TV to work as long as

they
> > don't wait for the equipment to climb out of the carton and install

itself..
>
> I get the Mt. Wilson UHF digital stations with a CM4228 antenna mounted

INSIDE
> in a north facing window from North County.


Yes. It's not an everyday occurrence, but I have gotten two LA UHF digitals
(KTLA-DT & KCBS-DT) with only a 2-bay bowtie about 9 feet above ground
level, inside my detached garage. The garage is on the southeast side of
the house, meaning the signals from Mt.. Wilson bend around the house (or
bounce off my neighbor's wall) and go through my garage wall before reaching
the bowtie. The bowtie was intended just for my locals.

Distance is about 124 miles.

I have a nice high-VHF antenna which will become important when LA Channels
7, 9, 11, and 13 flash cut their UHF digital to VHF digital. I built the
equivalent of a 4228 by coupling two 4-bay bowtie antennas together with a
phasing harness. It's unused, flat on the roof while I procrastinate over
buying a chimney mount. I tested it (very good) by tying its mast to the
chimney with rope, but that was just for a few days.

If it isn't obvious, I spend far more time playing with this stuff than
actually watching the TV pictures. ... this stuff and ham radio.


 
Alt 25.09.2008, 20:50   #6
UCLAN
 
Beiträge: n/a
Re: RCA Antenna Guide

Sal M. Onella wrote:

> I have a nice high-VHF antenna which will become important when LA Channels
> 7, 9, 11, and 13 flash cut their UHF digital to VHF digital. I built the
> equivalent of a 4228 by coupling two 4-bay bowtie antennas together with a
> phasing harness. It's unused, flat on the roof while I procrastinate over
> buying a chimney mount. I tested it (very good) by tying its mast to the
> chimney with rope, but that was just for a few days.


I am concerned about how well the 4228 will perform picking up 7, 9, 11 and
13 (especially 9) when they return to VHF. I have NOT seen a VHF antenna
equal in size or shape to the CM4228. I may lose the Lakers in February.

> If it isn't obvious, I spend far more time playing with this stuff than
> actually watching the TV pictures. ... this stuff and ham radio.


Getting LA OTAs has been a hobby of mine for over 30 years. (I had a
neighbor once who wondered why his tree died.) I have cable for the
SD stuff. I also experiment with antennas for reception of distant
signals on my scanner (BCD396T.) I had a neighbor once who was a ham.
I used to plug my scanner into his antennas and listen to marine
traffic well off of our coast. Fun stuff...
 
Alt 27.09.2008, 09:13   #7
Sal M. Onella
 
Beiträge: n/a
Re: RCA Antenna Guide


"UCLAN" <nomail@thanks.org> wrote in message
news:E3RCk.170$Un6.71@newsfe12.iad...

< snip >

> I am concerned about how well the 4228 will perform picking up 7, 9, 11

and
> 13 (especially 9) when they return to VHF. I have NOT seen a VHF antenna
> equal in size or shape to the CM4228. I may lose the Lakers in February.



There's good news. Some 4228 VHF testing has already been done and the
results are at

http://www.hdtvprimer.com/ANTENNAS/comparing.html.

Very near the bottom of the page you will see a chart displaying the gain
for UHF antennas at VHF frequencies. The 4228 appears to be among the best
but the news is not all good. When you get to that chart, you will see that
the gain curve is tilted across channel 9, rising from about 3 dB to 7 dB
across the channel width. Will your receiver will be OK with that much
differential? The 8VSB tuners like a flat-topped signal, not one with a
slope. Could hurt your chances.

Tell me, how well do you get analog channel 9 now? That's an indication.

Lastly, it is not difficult to fabricate a very effective Yagi antenna for
Channel 9 out of simple materials you probably have laying around. I can
talk you through it. (I wrote the description for making a Channel 2
antenna for a fellow in the rec.radio.amateur.antenna newsgroup about two
weeks ago.) If you have no time for such projects, you can buy a
single-channel yagi. Wade makes some.
http://www.wade-antenna.com/Wade/Yagi.htm as does Blonder Tongue. They are
not cheap.

In general, the Yagi characteristically has moderate forward gain and good
side rejection. (The 4228 has better rear rejection than the Yagi, based on
the graphs at http://www.hdtvprimer.com/ANTENNAS/cm4228.html and
http://www.hdtvprimer.com/ANTENNAS/w1713.html


 
Alt 27.09.2008, 20:37   #8
UCLAN
 
Beiträge: n/a
Re: RCA Antenna Guide

Sal M. Onella wrote:

> Tell me, how well do you get analog channel 9 now? That's an indication.


Unknown. I've only used the 4228 in conjunction with the "Add Digital
Channels" function of my TV. I might give the analog test a try next
time I have a few minutes to kill.

> Lastly, it is not difficult to fabricate a very effective Yagi antenna for
> Channel 9 out of simple materials you probably have laying around. I can
> talk you through it. (I wrote the description for making a Channel 2
> antenna for a fellow in the rec.radio.amateur.antenna newsgroup about two
> weeks ago.) If you have no time for such projects, you can buy a
> single-channel yagi. Wade makes some.
> http://www.wade-antenna.com/Wade/Yagi.htm as does Blonder Tongue. They are
> not cheap.
>
> In general, the Yagi characteristically has moderate forward gain and good
> side rejection. (The 4228 has better rear rejection than the Yagi, based on
> the graphs at http://www.hdtvprimer.com/ANTENNAS/cm4228.html and
> http://www.hdtvprimer.com/ANTENNAS/w1713.html


The problem with a Yagi is its length/depth. The CM4228 is only 6" long/deep,
while a Yagi would be at least 3' long/deep. Since this antenna is INSIDE in
a window, this is important.

I see, BTW, that the CW4228 has been replaced by the CW4228HD (with supposedly
better upper VHF performance.
 
Alt 28.09.2008, 09:48   #9
Sal M. Onella
 
Beiträge: n/a
Re: RCA Antenna Guide


"UCLAN" <nomail@thanks.org> wrote in message
news:B3vDk.367$uo6.170@newsfe04.iad...

< snip >

> The problem with a Yagi is its length/depth. The CM4228 is only 6"

long/deep,
> while a Yagi would be at least 3' long/deep. Since this antenna is INSIDE

in
> a window, this is important.


Oops. I didn't assume that the aforementioned window location was "It" for
your OTA antenna. Sorry. You must not have outside access for antennas,
either. A channel 9 Yagi would be even longer than 3 feet for appreciable
gain. Can you get to an attic location? VHF goes through most roofs
decently.
>
> I see, BTW, that the CW4228 has been replaced by the CW4228HD (with

supposedly
> better upper VHF performance.


Thanks. I'd like to take a look at that.


 
Alt 28.09.2008, 20:00   #10
UCLAN
 
Beiträge: n/a
Re: RCA Antenna Guide

Sal M. Onella wrote:

> Oops. I didn't assume that the aforementioned window location was "It" for
> your OTA antenna. Sorry. You must not have outside access for antennas,
> either. A channel 9 Yagi would be even longer than 3 feet for appreciable
> gain. Can you get to an attic location? VHF goes through most roofs
> decently.


I can get by with under 3' for 2.5 dB gain. I had a remodel done, and the
morons sealed off my attic access. Haven't gotten around to re-establishing
it yet. I have a big roof, but didn't want to hassle with masts, guy wires,
long cable runs, etc. We'll see what happens in February.
 
Alt 29.09.2008, 05:45   #11
Sal M. Onella
 
Beiträge: n/a
Re: RCA Antenna Guide


"UCLAN" <nomail@thanks.org> wrote in message
news:ACPDk.3873$NL4.3328@newsfe04.iad...
> Sal M. Onella wrote:
>
> > Oops. I didn't assume that the aforementioned window location was "It"

for
> > your OTA antenna. Sorry. You must not have outside access for

antennas,
> > either. A channel 9 Yagi would be even longer than 3 feet for

appreciable
> > gain. Can you get to an attic location? VHF goes through most roofs
> > decently.

>
> I can get by with under 3' for 2.5 dB gain. I had a remodel done, and the
> morons sealed off my attic access. Haven't gotten around to

re-establishing
> it yet. I have a big roof, but didn't want to hassle with masts, guy

wires,
> long cable runs, etc. We'll see what happens in February.


IMHO, the outside antenna is the only way to go for reliable distant
reception, except when the window faces the transmitters and you have an
unobstructed high-level view -- the equivalent of a roof mount.

Well, you alone know what you're willing and able to do (with antennas) and
you alone know how badly you want those Laker games. February is coming
fast!



Background experiment, inspired by this thread:

Step 1. I put my Hi-VHF log periodic on the peak of my Chula Vista roof
(about 20 feet above ground), aimed it toward LA and cabled it to the input
of an analog TV. Channel 9 was very bad, getting interference from both 8
and 10, as expected, since they are out in front of the antenna, within the
main lobe.

STEP 2: I put a switchable attenuator in line and saw a snowy but decent
picture from channel 9 when I attenuated the adjacent channel overload. 16
dB seemed about right, although this will vary, depending on the signal
strength from Channel 9 and the tuner characteristics.

STEP 3. I substituted a pair of channel-cut filters (Channels 8 & 10, of
course) for the attenuator and got about the same result.

OBSERVATION: A viewer in North County, with Channels 8 & 10 _behind_ him,
should expect an even better signal from LA's Channel 9 than I got..

CONCLUSION: I think you have reason for optimism. February is coming fast.
(Oops, I already said that.)


 
Alt 29.09.2008, 07:23   #12
UCLAN
 
Beiträge: n/a
Re: RCA Antenna Guide

Sal M. Onella wrote:

> IMHO, the outside antenna is the only way to go for reliable distant
> reception, except when the window faces the transmitters and you have an
> unobstructed high-level view -- the equivalent of a roof mount.


Well, the window faces north and has a clear shot at Mt. Wilson over the
ocean. Plus, it is less than 5 feet away from my TV, and is behind the
TV cabinet and is draped (so the 4228 cannot be seen from inside the house.)
A perfect match!

> Well, you alone know what you're willing and able to do (with antennas) and
> you alone know how badly you want those Laker games. February is coming
> fast!


I *may* have a upper VHF antenna installed with a vent pipe mount. That way
I can recover 7, 9, 11, and 13. But, maybe not.

> Background experiment, inspired by this thread:
>
> Step 1. I put my Hi-VHF log periodic on the peak of my Chula Vista roof
> (about 20 feet above ground), aimed it toward LA and cabled it to the input
> of an analog TV. Channel 9 was very bad, getting interference from both 8
> and 10, as expected, since they are out in front of the antenna, within the
> main lobe.


I have a 3-story apartment building to my south, blocking all SD signals.

> STEP 2: I put a switchable attenuator in line and saw a snowy but decent
> picture from channel 9 when I attenuated the adjacent channel overload. 16
> dB seemed about right, although this will vary, depending on the signal
> strength from Channel 9 and the tuner characteristics.
>
> STEP 3. I substituted a pair of channel-cut filters (Channels 8 & 10, of
> course) for the attenuator and got about the same result.
>
> OBSERVATION: A viewer in North County, with Channels 8 & 10 _behind_ him,
> should expect an even better signal from LA's Channel 9 than I got..


That's me!

It's on my list of "Things to do if I feel like it."
 
Alt 30.09.2008, 06:19   #13
Sal M. Onella
 
Beiträge: n/a
Re: RCA Antenna Guide


"UCLAN" <nomail@thanks.org> wrote in message
news:ZCZDk.3178$aV4.3003@newsfe10.iad...


< snip >

> ... my list of "Things to do if I feel like it."


I'm retired. That's the only list I have. ;-)


 
 


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