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post #12061 of 12520 Old 04-02-2015, 04:48 PM
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Quote:
Originally Posted by Calaveras View Post
In order of above:

1) UHF only
2) UHF with minimal VHF
3) UHF only
4) Low/High VHF and UHF (I wouldn't count on 100 miles for anything)

In the era of your TV antenna nobody separated low VHF (CHs 2-6) from high VHF (CHs 7-13). Today we do because few of the major broadcasters are using low VHF. Low VHF has a lot of manmade noise problems that made reception of analog stations less than perfect but wipes out digital stations. If you have a strong enough signal or live in a quiet location, low VHF works fine. An outdoor antenna is a requirement for low VHF.

Chuck
Oh, and this is one of the technical reasons why you can
use small antennas to get decent digital reception. Most
of the size of the old LPDA antennas that received low
VHF was for low VHF. They needed several large active
elements to get half-wave dipole reception across the
wide bandwidth of low VHF, and each one required a lot
of boom length to properly space the reflector/director
elements.

So, if you don't need low VHF, just saw off 90 percent
of the big end of your antenna and you're good to go...

--
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post #12062 of 12520 Old 04-02-2015, 07:11 PM
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Quote:
Originally Posted by maxreactance View Post
Gee, if you're getting all those channels, can I have your
"bad" antenna when you're done with it...

I do get about 95 channels myself, but some of those
listed I don't get at all; 32.2 and 32.4 may actually not
be transmitting a video picture at this time...

--
maxreactance
Fun day today. Ran some new cables. Borrowed and tried a Philmore amp. The amp reduced Channel 7 to almost 0, and did not significantly amplify the other stations.

Found the section on the Samsung where one can see the channel, physical channel, and db of SNR. Wrote down the figures of many stations, with and without a splitter, with RG6 and with a dinner coax, and also directly from the antenna with no splitter and only one TV. Got a headache.

Will post more later. Will try the ChannelMaster amp recommended in this thread.
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post #12063 of 12520 Old 04-02-2015, 09:12 PM
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Quote:
Originally Posted by PeninsulaMark View Post
Fun day today. Ran some new cables. Borrowed and tried a Philmore amp. The amp reduced Channel 7 to almost 0, and did not significantly amplify the other stations.
Will post more later. Will try the ChannelMaster amp recommended in this thread.
I have tried one of those new generation ELN (extreme low-noise) amps with low gains .... made for indoor antennas. (Has the CEA approved checkmark)
Except ... I did one thing different.
I hooked it up to a outdoor antenna model .... to test this extreme low noise claim.
I will guess the noise on this amp is 1db, and the gain(s) are somewhere between 7 to 13 db. Did not see any noticeable overloading.
The weakest signals showed some improvement.
The low amp gain(s) equalled my cable losses and probably gave a true signal capture at the antenna.

RCA 1450R (Walmart) .. $ 15
No specs given.

This is one of the better ones I have tested.
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post #12064 of 12520 Old 04-02-2015, 09:29 PM
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Originally Posted by 888CALLFCC View Post
gain(s) are somewhere between 7 to 13 db. Did not see any noticeable overloading.
The weakest signals showed some improvement.
RCA 1450R
No specs given.
Tested with ... KEMO, KRCB, KTLN, & KFTY-2, K03HY, KSBW, KVIE

Generally don't use amps for Sutro tower here .... due to signal overloading.

Last edited by 888CALLFCC; 04-02-2015 at 09:33 PM.
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post #12065 of 12520 Old 04-02-2015, 09:52 PM
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Signal strength and SNR fun and games

Quote:
Originally Posted by 888CALLFCC View Post
Tested with ... KEMO, KRCB, KTLN, & KFTY-2, K03HY, KSBW, KVIE

Generally don't use amps for Sutro tower here .... due to signal overloading.
With a Philmore DA27B in place, here are some sample readings in this order:

#bars /10, Channel, Physical Channel, SNR in db.

8, 54.1, 50, 27

1, 40.3, 40, 17

2, 36.1, 36, 17

1, 28.1, 28, 14 bad to no reception

10, 20.1, 20, 32

9, 9.1, 30, 30

3, 7.1, 7, 22 bad

9, 5.1, 29, 31

5, 4.1, , 21

1, 2.1, 48, 14 Bad

REMOVED AMP

6, 2.1, 44, 23

6, 7.1, , 25



CHANGE TO ONE SET DIRECT FROM ANTENNA

9, 11.1, , 31

10, 9.1, , 32

6, 7.1, , 25

10, 5.1, , 32

6, 4.1, ,24

5, 2.1, ,23


FOUR WAY SPLITTER ADDED

No change in values.


Although reception is fine on all the channels I watch, Channel 2 and 7 signal strength could be better.
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post #12066 of 12520 Old 04-02-2015, 10:12 PM
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Quote:
Originally Posted by PeninsulaMark View Post
With a Philmore DA27B in place, here are some sample readings in this order:

I looked up that amp. It's labeled as a high gain distribution amp with 25 dB gain on VHF and 21 dB gain on UHF. That's WAY too much gain for anything you could possibly need. Do not use that amp. It's likely to cause overload.

The hardest thing to get across to people is that more gain doesn't equal a better signal. If that was the case you could receive anything by having ever more gain. The issue is Signal-to-Noise ratio which is hard to improve even when you make all the right decisions in your setup.

Some of your SNRs are lower than I'd like to see but as long as they're stable then it's okay. Those 17's are not good.

BTW, 2.1 on 48 is a translator in Fremont so you shouldn't worry about that one.

It might be a bit overwhelming but you might read my article on preamps and noise found at the link below.

Chuck
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post #12067 of 12520 Old 04-02-2015, 11:20 PM
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Quote:
Originally Posted by Calaveras View Post
I looked up that amp. It's labeled as a high gain distribution amp with 25 dB gain on VHF and 21 dB gain on UHF. That's WAY too much gain for anything you could possibly need. Do not use that amp. It's likely to cause overload.

The hardest thing to get across to people is that more gain doesn't equal a better signal. If that was the case you could receive anything by having ever more gain. The issue is Signal-to-Noise ratio which is hard to improve even when you make all the right decisions in your setup.


Some of your SNRs are lower than I'd like to see but as long as they're stable then it's okay. Those 17's are not good.

BTW, 2.1 on 48 is a translator in Fremont so you shouldn't worry about that one.

It might be a bit overwhelming but you might read my article on preamps and noise found at the link below.

Chuck


That amp is gone. I'll look at your dissertations, but this video stuff is way over my head.

What would one see on the TV if there's "overload" from the amp ? No signal got stronger.

How many bars out of ten should I get for good viewing, viz what is the minimum ? What SNR is good ?

Why did Channel 7 crap out with that amp ?

Do these values indicate a new antenna is needed ?

The coax from the antenna is 58U, about 70 feet. Is it worth changing it to RG6 ?
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post #12068 of 12520 Old 04-02-2015, 11:45 PM
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Quote:
Originally Posted by Calaveras View Post
I looked up that amp. It's labeled as a high gain distribution amp with 25 dB gain on VHF and 21 dB gain on UHF. That's WAY too much gain for anything you could possibly need. Do not use that amp. It's likely to cause overload.

The hardest thing to get across to people is that more gain doesn't equal a better signal. If that was the case you could receive anything by having ever more gain. The issue is Signal-to-Noise ratio which is hard to improve even when you make all the right decisions in your setup.

Some of your SNRs are lower than I'd like to see but as long as they're stable then it's okay. Those 17's are not good.

BTW, 2.1 on 48 is a translator in Fremont so you shouldn't worry about that one.

It might be a bit overwhelming but you might read my article on preamps and noise found at the link below.

Chuck


What are you thoughts about this Amp ?: http://www.channelmaster.com/Antenna..._p/cm-3414.htm
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post #12069 of 12520 Old 04-03-2015, 07:00 AM
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Quote:
Originally Posted by PeninsulaMark View Post
That amp is gone. I'll look at your dissertations, but this video stuff is way over my head.

What would one see on the TV if there's "overload" from the amp ? No signal got stronger.

How many bars out of ten should I get for good viewing, viz what is the minimum ? What SNR is good ?

Why did Channel 7 crap out with that amp ?

Do these values indicate a new antenna is needed ?

The coax from the antenna is 58U, about 70 feet. Is it worth changing it to RG6 ?

With too much amplifier gain and strong signals the signals mix together and produce other signals in the TV band that can interfere with other stations. This can cause low SNRs or stations to completely drop out. In the case of channel 7 though, 2nd harmonics (2X the frequency) of FM stations can be produced in the TV tuner itself if the signals are too strong and cause interference to high VHF stations. An FM trap will eliminate this problem.

With the signal levels you have all the stations should have SNRs of 30dB or better. Just because you don't have SNRs that good doesn't mean your antenna is bad. You probably have some multipath issues (ghosts in the analog TV days). This is not a big deal as long as your stations are not dropping out.

I doubt you have RG-58 coax. That's 50 ohm coax and you can't get F connectors on it. It's more likely you have RG-59. RG-6 is better but that doesn't mean the RG-59 is a problem. It just has a little higher loss. If somehow you do have RG-58 then that should be changed.

At this point I'm a bit lost as to what problem we're trying to solve. I thought you were having dropouts on some of the SF stations. Is that still the case?

Chuck
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post #12070 of 12520 Old 04-03-2015, 07:11 AM
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Originally Posted by PeninsulaMark View Post
What are you thoughts about this Amp ?: http://www.channelmaster.com/Antenna..._p/cm-3414.htm
This is one of 4 distribution amps in this line. I use the CM3410. I have performed extensive measurements on it and it's top of its class. It has excellent overload characteristics. The amplifier section in the CM341x series is the same. The "x" indicates how many ways the signal is split; 0, 2, 4 or 8 ways. This amplifier is intended to be placed at the end of a run of coax and then short coax runs to each TV. This maintains the signal level and SNR that was present at the amplifier input for all TVs.

Chuck
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post #12071 of 12520 Old 04-03-2015, 08:43 AM
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Originally Posted by Calaveras View Post
This is one of 4 distribution amps in this line. I use the CM3410. I have performed extensive measurements on it and it's top of its class. It has excellent overload characteristics. The amplifier section in the CM341x series is the same. The "x" indicates how many ways the signal is split; 0, 2, 4 or 8 ways. This amplifier is intended to be placed at the end of a run of coax and then short coax runs to each TV. This maintains the signal level and SNR that was present at the amplifier input for all TVs.

Chuck

Okay ! Will take sample measurements today, without and with the CM in place. So after this amp, it seems that the runs should go directly to each TV. Right now my setup will have one splitter after this amp, and they are not "short", each being 30-50 ft.
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post #12072 of 12520 Old 04-03-2015, 08:48 AM
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Originally Posted by Calaveras View Post
With too much amplifier gain and strong signals the signals mix together and produce other signals in the TV band that can interfere with other stations. This can cause low SNRs or stations to completely drop out. In the case of channel 7 though, 2nd harmonics (2X the frequency) of FM stations can be produced in the TV tuner itself if the signals are too strong and cause interference to high VHF stations. An FM trap will eliminate this problem.

With the signal levels you have all the stations should have SNRs of 30dB or better. Just because you don't have SNRs that good doesn't mean your antenna is bad. You probably have some multipath issues (ghosts in the analog TV days). This is not a big deal as long as your stations are not dropping out.

I doubt you have RG-58 coax. That's 50 ohm coax and you can't get F connectors on it. It's more likely you have RG-59. RG-6 is better but that doesn't mean the RG-59 is a problem. It just has a little higher loss. If somehow you do have RG-58 then that should be changed.

At this point I'm a bit lost as to what problem we're trying to solve. I thought you were having dropouts on some of the SF stations. Is that still the case?

Chuck

Chuck, you are so right. Yes, the antenna has almost 100 feet of RG59U. Will there be significant improvement in the signal by changing it to RG6 quad shield ?
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post #12073 of 12520 Old 04-03-2015, 08:55 AM
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Quote:
Originally Posted by Calaveras View Post
With too much amplifier gain and strong signals the signals mix together and produce other signals in the TV band that can interfere with other stations. This can cause low SNRs or stations to completely drop out. In the case of channel 7 though, 2nd harmonics (2X the frequency) of FM stations can be produced in the TV tuner itself if the signals are too strong and cause interference to high VHF stations. An FM trap will eliminate this problem.

With the signal levels you have all the stations should have SNRs of 30dB or better. Just because you don't have SNRs that good doesn't mean your antenna is bad. You probably have some multipath issues (ghosts in the analog TV days). This is not a big deal as long as your stations are not dropping out.

I doubt you have RG-58 coax. That's 50 ohm coax and you can't get F connectors on it. It's more likely you have RG-59. RG-6 is better but that doesn't mean the RG-59 is a problem. It just has a little higher loss. If somehow you do have RG-58 then that should be changed.

At this point I'm a bit lost as to what problem we're trying to solve. I thought you were having dropouts on some of the SF stations. Is that still the case?

Chuck



I'm lost also ! There are no more drop-outs, and it is unclear why. Few days ago they stopped and I did nothing to make that happen. So I'm just optimizing what is here and trying to improve the weaker stations. My SO would like to watch KLFT (Channel 28.1 airs KFTL 28 with Christian inspirational programs) but even from the antenna coax the sets get 0-1 bars and rarely an image/sound.
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post #12074 of 12520 Old 04-03-2015, 09:24 AM
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I'm lost also ! There are no more drop-outs, and it is unclear why. Few days ago they stopped and I did nothing to make that happen. So I'm just optimizing what is here and trying to improve the weaker stations. My SO would like to watch KLFT (Channel 28.1 airs KFTL 28 with Christian inspirational programs) but even from the antenna coax the sets get 0-1 bars and rarely an image/sound.


I got what some said was "soft porn".

I had not looked at this station before.

Signal Quality needs to be 50% and above, they may have increased their power.

SHF
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post #12075 of 12520 Old 04-03-2015, 09:42 AM
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I got what some said was "soft porn".

I had not looked at this station before.

Signal Quality needs to be 50% and above, they may have increased their power.

SHF


Hmmm. That's not the Christian music station. Increased power in the past 24 hours ? Nice screen shot.
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post #12076 of 12520 Old 04-03-2015, 10:07 AM
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Quote:
Originally Posted by PeninsulaMark View Post
Okay ! Will take sample measurements today, without and with the CM in place. So after this amp, it seems that the runs should go directly to each TV. Right now my setup will have one splitter after this amp, and they are not "short", each being 30-50 ft.
Quote:
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Chuck, you are so right. Yes, the antenna has almost 100 feet of RG59U. Will there be significant improvement in the signal by changing it to RG6 quad shield ?

RG-59 is 3 to 4 dB more loss at the top of the UHF band than RG-6. There could be a difference on the weakest stations. You should find that you don't loose stations with the CM3414. If you're still having problems with KGO 7 then you probably need an FM trap ahead of the DA. Splitting after the distribution amp is not a good idea. If you need more than 4 splits then get a CM3418.

Chuck
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post #12077 of 12520 Old 04-03-2015, 10:09 AM
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Hmmm. That's not the Christian music station. Increased power in the past 24 hours ? Nice screen shot.
It soon went to unusable.

Quote:
My SO would like to watch KLFT
That is not a local station.

And KAXT which has many audio only streams appears to be off the air.

What call letters again and the RF channel again please.

SHF
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post #12078 of 12520 Old 04-03-2015, 10:15 AM
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I'm lost also ! There are no more drop-outs, and it is unclear why. Few days ago they stopped and I did nothing to make that happen. So I'm just optimizing what is here and trying to improve the weaker stations. My SO would like to watch KLFT (Channel 28.1 airs KFTL 28 with Christian inspirational programs) but even from the antenna coax the sets get 0-1 bars and rarely an image/sound.

KFTL shouldn't be that weak where you are but it is sandwiched in between 27 and 29 which are both very strong. It could be an adjacent channel issue. OTOH, it should be no more than 20 dB weaker than 27 and 29. TVs are supposed to be able to handle at least 33 dB weaker adjacent stations.

You want to look at 3 also since it has Christian programming.

Chuck
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post #12079 of 12520 Old 04-03-2015, 10:16 AM
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What call letters again and the RF channel again please.

SHF

You had it. He means KFTL on 28.

Chuck
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post #12080 of 12520 Old 04-03-2015, 10:38 AM
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Signal Quality needs to be 50% and above, they may have increased their power.

SHF

Why is the Signal Quality so low with a Signal Strength of 76%?

I don't understand why people in the Bay Area are having so much trouble with these low power stations.

At Mark's place TV Fool show KFTL with a NM of 44 dB. That's only 14 - 17 dB weaker than KTSF 27 and KPIX 29. There should be no issue with that.

If I had a 15KW station 21 miles away LOS it would be too strong. I've got KMMW on 28 (when it's on the air) 14 miles away with only 250 watts with a measured noise margin of 43 dB. There must be some problem experienced in the Bay Area that I'm missing.

Chuck
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post #12081 of 12520 Old 04-03-2015, 11:25 AM
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Why is the Signal Quality so low with a Signal Strength of 76%?

I don't understand why people in the Bay Area are having so much trouble with these low power stations.
...
Chuck
It must be multipath, Terry said long ago that we live in the land of multipath. On the bottom (~ Sea Level) of a bowl surrounded on all sides by mountains on the rim of the bowl.

When my new antenna system was put up I had lots of problems with KKPX VC 65 RF 41.

Look at it just now today:



Back then I needed to use my Terk HDTVa on top of a bookshelf which is now disconnected. I also needed to use it for KPIX pointed due West out to the ocean and far away from Sutro to the North West at times.

And there is the Samsung table top antenna pointed almost directly at my furnace (Just like my old furnace) to the South East for KQEH which is to the North East.

That direction for the KQEH dedicated antenna was discovered and has been consistently the best direction but has periodically breakups due to airplane landing and taking off from San Jose. Thus I use 30.2 instead. 54.3 (PBS LIFE) it is used for and has the airplane problems.

So, you buys your house an must live with the location problems ~ 45 years later.

OH, and there is the DSL speed limit imposed by the cable under the street to:



I even got a free modem when my old one gave ~ 1.3. Big increase and I am paying for 3.0.

SHF
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KAXT Channel 1 is on again after being out for several hours.
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post #12083 of 12520 Old 04-03-2015, 12:38 PM
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Quote:
Originally Posted by Calaveras View Post
You had it. He means KFTL on 28.

Chuck
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It soon went to unusable.



That is not a local station.

And KAXT which has many audio only streams appears to be off the air.

What call letters again and the RF channel again please.

SHF

Not local ? It seems to be in San Framcisco. I'm not religious, but the music and videos were pretty the few minutes that it appeared.

Why do you think it is not local ?
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post #12084 of 12520 Old 04-03-2015, 12:42 PM
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KAXT Channel 1 is on again after being out for several hours.
They now appear to have only one audio only stream which Larry has correct and I never saw change.

Total of almost exact ally six (6)hours according to Toast0's chart.

SHF
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post #12085 of 12520 Old 04-03-2015, 12:57 PM
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How many bars out of ten should I get for good viewing, viz what is the minimum ? What SNR is good ?
These questions haven't been answered for you yet, so let me explain the difference between the "bars" reading and "SNR".

Signal indication by bars or, on many TV receivers, by a 0 to 100 scale, have no standard reference. Each manufacturer has their own idea of what value should be shown for a certain signal, and it varies greatly. If you put the exact same signal into five different tuners, you would probably see five different readings. You might see two bars on one, 5 bars on another: 20 on one 0-100 scale and 60 on another. You can't compare the reading on one TV to that of another TV using the bars or 0-100 scale. These scales can only be used to show the differences in signals on that particular TV. Also bars and 0-100 scales can show signal strength or they can show signal quality. Unless it's specified in the manual that came with the TV, you have no idea what they're actually showing.

I have several tuners and on one I can get a picture with 1 bar, but on another you need 5 bars to produce a picture. Another will show 10 on the 0-100 scale when a picture shows up, while on another you need a signal of 50 or better to get a picture.

The HD Home Run receivers show both signal strength and signal quality on their readouts. (See the examples above that Stephen Fischer posted.) With these receivers you need a signal strength AND a signal quality reading of 50 or higher each to get a picture. You can have a signal strength of 100 and still not get a picture if the signal quality is below 50. Multipath reflections cause the signal quality to vary greatly as you turn your antenna with a rotor or switch from one antenna to another as I do. I think that's why we here in the Bay Area have so many reception problems.

While bars and 0-100 scale readings have no standard, the SNR (Signal to Noise) reading in dB is a standard. Using it you know exactly how strong the signal actually is. Most TV receivers don't show the SNR reading, though. For those that do, you can use this reading and compare it to another SNR reading from a different receiver. Using the same example used above where you put the exact same signal into five different tuners, all should show the exact same SNR dB reading.

You need a signal strength of 15.2 dB SNR to produce a picture. Since SNR is a standard, this is the same on every tuner. Some call this the "cliff edge". Below 15.2 you get no picture; above 15.2 you do. The higher the dB reading is, the better the signal is. 15.2 to 16 dB will produce a picture, but you'll still see pixelation and occasional break up. You really need 17 dB to get rid of the pixelation and get a solid, clear picture. For reliable viewing, you should have a nominal signal of at least 20 dB from a station to allow for signal variations. Signals can vary several dB up and down due to changes in atmospheric conditions. If you can't get a signal of at least 20 dB on average, you can expect occasional drop outs, or times when the signal will disappear completely for a while.

Some tuners show a maximum reading of 27 dB SNR, while others show higher readings. The highest SNR reading I've seen on any TV is 33 dB.

Larry
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post #12086 of 12520 Old 04-03-2015, 01:05 PM
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Originally Posted by SFischer1 View Post
They now appear to have only one audio only stream which Larry has correct and I never saw change.
SHF
KAXT dropped audio sub-channels 14 through 20 several months ago. Most had no audio anyway. 1.13 has been silent a lot since the change. I don't receive the station that often here, so I don't know what's on 1.13 now.

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Not local ? It seems to be in San Framcisco. I'm not religious, but the music and videos were pretty the few minutes that it appeared.

Why do you think it is not local ?
Unless you made a typo, when it did not show up in Larry's list (Hit F3 in IE) I searched the FCC records.

Quote:
CHRISTIAN BROADCASTING INC
E
88.1 MHZ
IA ,
STORM LAKE
LA
BLED-20121113ABS
KLFT 172397
TALENTS MINISTRY, INC.
There are lots of other entries that do not make sense for me that the FCC found. (The search method and what is displayed has changed since the last time I did a DTV station search.

Expert advice needed to find KLFT, I must admit failure.

I see nothing on VC 28 or RF 28 in Larry's list for any location for KLFT.

SHF
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Originally Posted by Larry Kenney View Post
These questions haven't been answered for you yet, so let me explain the difference between the "bars" reading and "SNR".

Signal indication by bars or, on many TV receivers, by a 0 to 100 scale, have no standard reference. Each manufacturer has their own idea of what value should be shown for a certain signal, and it varies greatly. If you put the exact same signal into five different tuners, you would probably see five different readings. You might see two bars on one, 5 bars on another: 20 on one 0-100 scale and 60 on another. You can't compare the reading on one TV to that of another TV using the bars or 0-100 scale. These scales can only be used to show the differences in signals on that particular TV. Also bars and 0-100 scales can show signal strength or they can show signal quality. Unless it's specified in the manual that came with the TV, you have no idea what they're actually showing.

I have several tuners and on one I can get a picture with 1 bar, but on another you need 5 bars to produce a picture. Another will show 10 on the 0-100 scale when a picture shows up, while on another you need a signal of 50 or better to get a picture.

The HD Home Run receivers show both signal strength and signal quality on their readouts. (See the examples above that Stephen Fischer posted.) With these receivers you need a signal strength AND a signal quality reading of 50 or higher each to get a picture. You can have a signal strength of 100 and still not get a picture if the signal quality is below 50. Multipath reflections cause the signal quality to vary greatly as you turn your antenna with a rotor or switch from one antenna to another as I do. I think that's why we here in the Bay Area have so many reception problems.

While bars and 0-100 scale readings have no standard, the SNR (Signal to Noise) reading in dB is a standard. Using it you know exactly how strong the signal actually is. Most TV receivers don't show the SNR reading, though. For those that do, you can use this reading and compare it to another SNR reading from a different receiver. Using the same example used above where you put the exact same signal into five different tuners, all should show the exact same SNR dB reading.

You need a signal strength of 15.2 dB SNR to produce a picture. Since SNR is a standard, this is the same on every tuner. Some call this the "cliff edge". Below 15.2 you get no picture; above 15.2 you do. The higher the dB reading is, the better the signal is. 15.2 to 16 dB will produce a picture, but you'll still see pixelation and occasional break up. You really need 17 dB to get rid of the pixelation and get a solid, clear picture. For reliable viewing, you should have a nominal signal of at least 20 dB from a station to allow for signal variations. Signals can vary several dB up and down due to changes in atmospheric conditions. If you can't get a signal of at least 20 dB on average, you can expect occasional drop outs, or times when the signal will disappear completely for a while.

Some tuners show a maximum reading of 27 dB SNR, while others show higher readings. The highest SNR reading I've seen on any TV is 33 dB.

Larry

Totally understandable. You are a professor and a fast accurate typist. Thank you. Will take measurements of every visible channel and the SNR, without and with the CM amp.
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Originally Posted by SFischer1 View Post
Unless you made a typo, when it did not show up in Larry's list (Hit F3 in IE) I searched the FCC records.



There are lots of other entries that do not make sense for me that the FCC found. (The search method and what is displayed has changed since the last time I did a DTV station search.

Expert advice needed to find KLFT, I must admit failure.

I see nothing on VC 28 or RF 28 in Larry's list for any location for KLFT.

SHF


Is that their corporate office or transmitter location or both ? Here they assert they are in the East Bay of San Francisco: http://streema.com/tv/KFTL_TV

and they mention Christian music.

Last edited by PeninsulaMark; 04-03-2015 at 03:24 PM.
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post #12090 of 12520 Old 04-03-2015, 03:35 PM
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Originally Posted by PeninsulaMark View Post
Is that their corporate office or transmitter location or both ? Here they assert they are in the East Bay of San Francisco: http://streema.com/tv/KFTL_TV

and they mention Christian music.

You typed KLFT!
Quote:
I'm lost also ! There are no more drop-outs, and it is unclear why. Few days ago they stopped and I did nothing to make that happen. So I'm just optimizing what is here and trying to improve the weaker stations. My SO would like to watch KLFT (Channel 28.1 airs KFTL 28 with Christian inspirational programs) but even from the antenna coax the sets get 0-1 bars and rarely an image/sound.
SHF
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