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I'm getting a much stronger signal here in Fremont... from the low 60s (on RF 42) to the mid 80s (on RF 22) on the backside of CM4228 antenna and on my indoor bowtie antenna pointed towards the tower I'm now getting 100 signal. Both antennas are amplified.
 

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Thanks for the outdoor recommendation again.



Seriously considering an outdoor solution, but I really have not spent much time on this endeavor so far. I also have enjoyed the challenge and learning experience of this project, otherwise I would have stuck with satellite and streaming for care-free entertainment....


As other folks have mentioned previously an indoor is perhaps the only solutions (i.e. apartment dwellers) or like me , they want to use whatever they already have on-hand (all projects have some constraints and restrictions and need to be accomplished within some resource limits).
@Dennis Young - we are neighbors! :) Just noticed you posted your approx location in an early post and we are in the same place.

I agree that many people, especially in the Bay Area, live in apartments/condos and so that outdoor rooftop antenna is not an option. I tried several times installing a decent outdoorsy antenna in my balcony and it did worse than an indoor antenna. Whereas indoor, I found a couple of super-sweet indoor spots that I can pickup all the stations except KRON and KOFY... I have a reference indoor antenna I kept from the old days when I worked on digital tuner and demod designs, it's truly one of the best antenna and it's ability to pickup without an amp is just amazing.

I have another home in central valley and an outdoor antenna was not able to pickup RF20 from Stockton/Lodi area but the indoor antenna could (also in a funky sweet spot), which made my parents really happy to pick up KTSF shared on RF20 for their Asian programs. I would not knock an indoor antenna... A well designed indoor antenna can perform surprisingly well.
 

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We lit up KAXT/KTLN tonight on RF channel 22. 42 will shut down on 7/3. How does the new 22 compare to the current 42 from your location?
San Francisco-Castro/Noe Valley area
I have four antennas... here are the results for each. Signals are shown as signal strength/signal quality from an HD Home Run receiver.
Antenna Ch 22 Ch 42
LP345 @350 degrees 72/26 No pic 74/30 No pic
SR15 @ 200 degrees 67/32 No pic 71/69 OK
XG91 @ 190 degrees 60/52 OK 59/0 No pic
Winegard 8200U - Three positions where signals peaked
@ 125 degrees 70/65 OK 70/43 No pic - I have a 1000' hill a couple blocks away in this direction
@ 220 degrees 81/67 OK 79/43 No pic - My best position for Mt Allison stations
@ 330 degrees 76/59 OK 70/64 OK

Conclusion: There's not a huge difference in the signals coming from the two channels, but channel 22 has a slight edge using the 8200.

Larry
 

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I have another home in central valley and an outdoor antenna was not able to pickup RF20 from Stockton/Lodi area but the indoor antenna could (also in a funky sweet spot), which made my parents really happy to pick up KTSF shared on RF20 for their Asian programs. I would not knock an indoor antenna... A well designed indoor antenna can perform surprisingly well.

I wish I could examine firsthand what was going on since the outdoor antenna not receiving KDTV when the indoor did makes no sense at all. Something is missing. Stockton to Galt is actually a hot spot for KDTV so it's no surprise that it can be received there. Any decent antenna should work. But it could be that the outdoor antenna was getting too much interference from K20JX Sacramento, also on RF 20 and the indoor antenna was not in its "sweet spot." This does not imply that there's anything special about that particular indoor antenna. Probably any of many models would work in the optimum location.

OTA is like real estate: Location, location, location.

I made a comparison for the stations around here. See attached image. The yellow trace is my 37 element LPDA outdoor antenna and the magenta trace is my 8 element LPDA antenna used indoors. The stations with callsigns in cyan are 77 miles and 1 edge away. The 2 stations in orange are just 13 miles away and LOS even from inside the house. The 2 LOS stations can easily be received with high SNRs on the indoor antenna. None of the stations 77 miles away can be received with the indoor antenna.

The best stations to compare are KTTU, KVOA, KUAT and KOLD. KMSB and KUVE-DT have co-channel Mexican stations. On the indoor antenna those 4 stations are around 30 db weaker on the indoor antenna. The LOS stations are only 10-15 db weaker.

Under the right conditions, an indoor antenna can work just fine, but in many situations it doesn't.

Chuck
 

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I wish I could examine firsthand what was going on since the outdoor antenna not receiving KDTV when the indoor did makes no sense at all. Something is missing. Stockton to Galt is actually a hot spot for KDTV so it's no surprise that it can be received there. Any decent antenna should work. But it could be that the outdoor antenna was getting too much interference from K20JX Sacramento, also on RF 20 and the indoor antenna was not in its "sweet spot." This does not imply that there's anything special about that particular indoor antenna. Probably any of many models would work in the optimum location.

OTA is like real estate: Location, location, location.

I made a comparison for the stations around here. See attached image. The yellow trace is my 37 element LPDA outdoor antenna and the magenta trace is my 8 element LPDA antenna used indoors. The stations with callsigns in cyan are 77 miles and 1 edge away. The 2 stations in orange are just 13 miles away and LOS even from inside the house. The 2 LOS stations can easily be received with high SNRs on the indoor antenna. None of the stations 77 miles away can be received with the indoor antenna.

The best stations to compare are KTTU, KVOA, KUAT and KOLD. KMSB and KUVE-DT have co-channel Mexican stations. On the indoor antenna those 4 stations are around 30 db weaker on the indoor antenna. The LOS stations are only 10-15 db weaker.

Under the right conditions, an indoor antenna can work just fine, but in many situations it doesn't.

Chuck
Outdoor antenna is mainly about height... high enough to clear a lot of obstructions, which isn't always the case. Plus, with a pole, of which you can only vary the height (z) and direction - it's way more than just throw up an antenna. There also people installing outdoor antenna not with a pole but mounted on the one of the exterior walls...due to HOA limitations and what not, which can also have just many issues as indoor antenna. With an indoor antenna, you can also change x and y but obviously limited in z. Fortunately, I was able get all the Walnut Grove transmitted stations, plus Fremont Peak's.

I brought over 6 different antenna types and only one was able to pick up the signal, high SNR, high symbol rate. There are definitely differences in indoor antenna designs, no less than outdoor antenna. If anything, I'd argue more have gone into indoor antenna design in recent years than outdoor antennas.

In Stockton/Lodi area, you would be pointing to the north to pick up the cluster of towers in Walnut Grove, but point to southwest to reach Fremont Peak, and it's not easy to find that sweet spot that you can pick up both cluster of towers. I spent less time with the indoor antenna than I did with the outdoor one... After I left, my parents told me RF20 held up very well day time and night time.
 

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I brought over 6 different antenna types and only one was able to pick up the signal, high SNR, high symbol rate. There are definitely differences in indoor antenna designs, no less than outdoor antenna. If anything, I'd argue more have gone into indoor antenna design in recent years than outdoor antennas.
If you were to model those 6 antennas you'd find they're not all that different from each other. For antennas that are about the same size it isn't possible for one to be significantly better than the rest unless the rest are total garbage. I'm assuming though that some thought went into the design of all of them. You never see any technical data (patterns, gain, etc.) on any of these indoor antennas because none would be very good. If one performs better than the rest in a certain situation it's most likely has to do with the pattern that happens to be favorable for the particular location. The same antenna could be a complete non-starter at the next location. If there was one superior design out there, it would have been identified and we'd all recommend it. There is no magic antenna design out there. If you want a superior indoor antenna, use an outdoor antenna indoors.

Watch Antenna Man's YouTube videos and see what he has to say about those indoor antennas.

Over the many years I've been doing this I've heard many wildly impossible anecdotal claims for the performance of one antenna over another. The American Radio Relay League accepts only modeling data in QST antenna advertisements because of wild claims. I'm just trying to inject a little sanity into the discussion here.

I recently completed swapping out my high VHF antennas for the 14 element yagi on a 10' boom I posted recently. On the low tower I replaced a 22 element LPDA on an 18' boom with the 14 element (optimized for gain). The LPDA was about 1 dB better than the yagi. On the big tower at 62' I was using a 10 element yagi on a 5' boom. This antenna was optimized for minimal side and back lobes and not gain. The 14 element was about 4 dB better. These results were right where you'd expect them to be. The point is that it's very hard to get more gain once you have an antenna that works correctly. To get 3 dB you need to double the antenna size. There is no design to get 3 dB more gain out of the same sized antenna.

Chuck
 

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Watch Antenna Man's YouTube videos and see what he has to say about those indoor antennas.
I watch his videos regularly but I would not claim he is the ultimate expert or that his opinion is the only one matters. After all, I did work on designing tuner, demod and so on, I know more about RF than most people. He has serious bias towards things. He hates flat antenna with a passion and he also hate cheap Walmart outdoor antenna.

I used to believe him until I started using flat antennas trying to do an array antenna for my work, and he is dead wrong! There is no perfect antenna and flat antenna is nowhere as bad as he claims. His approach of just dropping the antenna on the same spot to test, without taking into consideration the pickup pattern of the antenna is flawed. It's because he try to simplify multi-dimension issue to a single dimension. EVERY antenna needs to be positioned when its far from the signal source and signal level is low or fluctuating. A sweet spot for antenna A doesn't necessary mean it's a sweet spot for antenna B - same applies to different designs of a flat antenna.

I have positioned a flat antenna that he dislikes, in downtown San Jose for my friend in a 2nd floor apartment, and he was able to pick all the stations in the bay area except VHF stations. It's all about finding the right spot and there is some technique to it.
 

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Calaveras is right. Don't forget that. However, a chance of reception of above the threshold of 1% is worth trying with any antenna. It's easier with indoor ones.
 

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This isn't helpful and I thought personal attacks were not allowed here. If you disagree with something I wrote please present your argument but be prepared to defend it.

Chuck
No attack intended Chuck. I was expressing support for your counsel here. Your opinions are more valuable than mine here. Science tends to work better than luck, and I understand this. Mods, feel free to delete that post.
 

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I watch his videos regularly but I would not claim he is the ultimate expert or that his opinion is the only one matters. After all, I did work on designing tuner, demod and so on, I know more about RF than most people.
That's wonderful but I don't know what that has to do with antennas. What is your antenna experience?


I used to believe him until I started using flat antennas trying to do an array antenna for my work, and he is dead wrong! There is no perfect antenna and flat antenna is nowhere as bad as he claims.
I guess it's what you consider to be a bad antenna. If you only call an antenna "bad" if it doesn't receive anything then there may be no bad antennas. Any piece of metal will receive signals if they're strong enough. A friend in Walnut Creek was able to receive the Sacramento UHF stations with a dipole made out of tin foil connected to the back of his TV. I'd still call that a bad antenna.


His approach of just dropping the antenna on the same spot to test, without taking into consideration the pickup pattern of the antenna is flawed. It's because he try to simplify multi-dimension issue to a single dimension. EVERY antenna needs to be positioned when its far from the signal source and signal level is low or fluctuating. A sweet spot for antenna A doesn't necessary mean it's a sweet spot for antenna B - same applies to different designs of a flat antenna.
I have to disagree with this. This is not my experience and I can think of no theory to support this. Hot spots and cold spots (that's what I call them) are determine by the RF field at any location. That doesn't change because you put a different antenna in the spot. I tested a lot of different antennas in two locations where I used to live. Signals strengths and multipath were different between the two locations but the relative strengths and SNRs between stations at one location did not change much with the antenna. If you're seeing big differences between strengths and SNRs between antennas in the same location then something is wrong with the antennas.

From looking at holl_ands antenna models the typical flat panel design has a bi-directional lobe perpendicular to the physical plane of the antenna.

You want to test antennas in the same location because the RF field strength of the stations stays about the same over time. It's not a perfect test though since signals do vary throughout the day and over longer periods. If you move the antenna then any hope for fairly constant field strengths goes out the window.


I have positioned a flat antenna that he dislikes, in downtown San Jose for my friend in a 2nd floor apartment, and he was able to pick all the stations in the bay area except VHF stations. It's all about finding the right spot and there is some technique to it.
I can't speak for him but I've never said an indoor antenna can't work. What I say is that it's at a severe disadvantage to an outdoor antenna. Clearly that's the case in my example above with the indoor antenna performing 10-30 dB worse than the outdoor antenna. Such an antenna may receive everything you want but that doesn't make it a good antenna in my book. :)

Chuck
 

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No attack intended Chuck. I was expressing support for your counsel here. Your opinions are more valuable than mine here. Science tends to work better than luck, and I understand this. Mods, feel free to delete that post.

Then I apologize that I took it the wrong way.

Chuck
 

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I'm getting a much stronger signal here in Fremont... from the low 60s (on RF 42) to the mid 80s (on RF 22) on the backside of CM4228 antenna and on my indoor bowtie antenna pointed towards the tower I'm now getting 100 signal. Both antennas are amplified.

Do you think you should be using an amp when you're right on top of the tower?
 

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That's wonderful but I don't know what that has to do with antennas. What is your antenna experience?




I guess it's what you consider to be a bad antenna. If you only call an antenna "bad" if it doesn't receive anything then there may be no bad antennas. Any piece of metal will receive signals if they're strong enough. A friend in Walnut Creek was able to receive the Sacramento UHF stations with a dipole made out of tin foil connected to the back of his TV. I'd still call that a bad antenna.




I have to disagree with this. This is not my experience and I can think of no theory to support this. Hot spots and cold spots (that's what I call them) are determine by the RF field at any location. That doesn't change because you put a different antenna in the spot. I tested a lot of different antennas in two locations where I used to live. Signals strengths and multipath were different between the two locations but the relative strengths and SNRs between stations at one location did not change much with the antenna. If you're seeing big differences between strengths and SNRs between antennas in the same location then something is wrong with the antennas.

From looking at holl_ands antenna models the typical flat panel design has a bi-directional lobe perpendicular to the physical plane of the antenna.

You want to test antennas in the same location because the RF field strength of the stations stays about the same over time. It's not a perfect test though since signals do vary throughout the day and over longer periods. If you move the antenna then any hope for fairly constant field strengths goes out the window.




I can't speak for him but I've never said an indoor antenna can't work. What I say is that it's at a severe disadvantage to an outdoor antenna. Clearly that's the case in my example above with the indoor antenna performing 10-30 dB worse than the outdoor antenna. Such an antenna may receive everything you want but that doesn't make it a good antenna in my book. :)

Chuck
I now understand why certain members of this forum have strong opinions about you.


If you don't know how a tuner/demod designer would know about RF and antenna, then it's pretty sad and shocking. We look at how to take a received signal, no matter how degraded it is through various RF anomalies, and try to come up with a circuit design or algorithm to get a lock, stay locked, and recover as much data from it as possible. That means understanding the effects of an antenna design, looking at how to turn destructive interference into constructive interference, mitigate the interference, how to dynamically generate filter mask based on real conditions, tweak the loop back, etc, etc, etc, to deal with RF issues. THIS IS WHY you now have cheap TV that can lock onto a signal way better than an expensive TV from years ago, from the exact same antenna. You clearly have very little exposure or understanding of that, and how that is completely interlocked with the antenna. Basically, tuner design has to accommodate real world issues from real world antenna, good or bad, so yes, a good RF engineer or tuner design know a lot about antennas.

As far as testing is concerned and using your term of hot spot and cold spot, it does not make sense to drop a new antenna to the exact test spot without taking the polar plot, not just planar, but a spherical polar plot of the antenna receiving characteristics, into consideration. The orientation of an antenna to maximize "hot spot" vary depend on the design. This is only fair to do if you are testing the same type of antenna, i.e., flat, or aerial multi-element. Crosstype testing by just dropping it on a fixed location is not fair or fully scientific.

Antenna Man's test method is a mixture of being subjective and objective. The objective part of it is he use the same TV, and using the signal level readout from the TV as metric. He does that with a comparison to previous 2 products he tested. Using this signal level is not very meaningful... Since you can have very strong signal but a lot of interferences thus result in high energy level but low quality data, it's silly to use just one metric to rank the received signal quality. Antenna Man's method is borderline layperson approach with some repeat consistency. I know this because we, in the industry, uses multiple metrics to judge, i.e, signal power level, SNR, symbol quality, constellation accuracy like coherency and phase noise and so on. You can easily create conditions with low "signal level" but high symbol quality, resulting in very low error rate of the data stream. IN ADDITION, he did not retest the 2 previous products on the same day of testing the new product, to correlate any potential atmospheric or weather variations, or potential changes made to the transmitter since previous test runs. That alone is enough to say that test is not fully scientific and in a fair and controlled manner. Before you counter back, I did check, and his 2 previous results listed are the exact values from the previous testing, so he didn't re-run the test on the day of testing the new antenna.

The subjective part of his testing comes from him wanting to streamline and simplify the test, so he can make videos faster... so he drop the device into the same spot, without considering the differences of hot/cold spots as a result of the antenna configuration differences.

On the topic of modeling, this is something we do in my line of work every day...day in and day out. I am working on multi-element and multi-dimension arrays. Models are created by people, using formulas and theoretical design principals. The model is only as good as how it is designed. For companies with vested interest, the model would then get improved continuously to accommodate real life performance delta, so overtime, the model becomes more accurate. Even then, the model doesn't always match real world performance. To model effectively in a computationally practical way, assumptions are made to reduce complexity, so many variations are fixed, hence a honest engineer would list out those limits and stating the assumed condition of the model.

The truth is there is no perfected model of antenna design or RF for that matter, if there is, NONE OF US would be making different products and we would be all making that one single perfect product. And the truth is if the model is that amazing, then we would never have real-world performance delta to what's generated by the model. There is no peer reviewed scientific proof that flat category of antenna design is inferior - that's just one guys' arrogant opinion.

There is also no magical metal alloy used on outdoor antenna that makes it more superior to metal/conductor used in indoor antenna. The key difference for outdoor antenna is 1) height, reducing ground level interference; 2) space to build multi-elements that is not so possible for smaller indoor antenna. Hot and cold spots exist for outdoor antenna, too. That's why we spend all this time talking about positioning and directional setting. Indoor antenna, being that it's small and portable, is much easier to move around. It can be just as effective, assume your indoor condition is not just "cold spots". That flexibility of moving the antenna around mostly does not exist for outdoor antenna.

You know more than a layman about this but it doesn't mean there aren't others with equal or more knowledge. TV reception is not just about the antenna. The cable, tuner effectiveness, demod efficiencies all contribute. Lobe diagram of an antenna is just one data point, it assume the antenna is placed in one fixed position. With the film based flat antenna, I can affix it to different places and because they are light, I can use putty to secure its base and have n-degree freedom in x,y,z to adjust its placement and compensate for a lot of issues. It's way more than what you can do with outdoor antenna once it's on the pole. Hence all the discussions are about a particular design on elements, number of elements, their placement, reflectors and so on. Because you no longer have the flexibility to move it in x,y,z, so you add more elements to increase ways the signal can be picked up.

Time after time, I have been able to, with time spent and proper tracking, to find that sweet spot and use an indoor antenna to pick up a lot of channels in a very stable manner. I am not suggesting outdoor antenna sucks. What I am saying is indoor antenna can be very effective if you know what you are doing.
 

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Time after time, I have been able to, with time spent and proper tracking, to find that sweet spot and use an indoor antenna to pick up a lot of channels in a very stable manner. I am not suggesting outdoor antenna sucks. What I am saying is indoor antenna can be very effective if you know what you are doing.

I'll try not to get carried away here. People get tired of these drawn out discussions real fast. You've accused me of all sorts of stuff I didn't say, never thought, isn't true, but so be it. I'm used to it. It happens all the time. People read all sorts of things into the text that was not there.

My question about your antenna experience didn't tell you what you thought. I asked that because all the tests you'd need to perform can be run on the bench with test equipment and no antenna. Instead you made assumptions, went on a rant accusing me of various untrue things.

I clearly said Antenna Man's tests are not perfect. That includes all the reasons you said. Ideally he should test all antennas in a short time but that's not practical. He does the next best thing. In general the antennas I'd expect to perform better do and ones I'd expect to perform worse do.

I don't know why people get so defensive about indoor antennas. It's not controversial to say an indoor antenna is at a distinct disadvantage to an outdoor antenna. That's all I've ever said. I have not ever said you can't receive any stations on an indoor antenna. The FCC assumes an outdoor antenna at 30' for DTV reception. All you're doing by moving an antenna around the house is hoping to stumble upon a spot that has a strong enough signal and low enough multipath to allow the tuner to decode it. This could be easy, difficult or impossible. No moving an antenna around my house is going to receive the Tucson stations. They are simply too weak. OTOH, my two LOS stations can be received with the antenna anywhere in the house.

Chuck
 

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I'll try not to get carried away here. People get tired of these drawn out discussions real fast. You've accused me of all sorts of stuff I didn't say, never thought, isn't true, but so be it. I'm used to it. It happens all the time. People read all sorts of things into the text that was not there.

My question about your antenna experience didn't tell you what you thought. I asked that because all the tests you'd need to perform can be run on the bench with test equipment and no antenna. Instead you made assumptions, went on a rant accusing me of various untrue things.

I clearly said Antenna Man's tests are not perfect. That includes all the reasons you said. Ideally he should test all antennas in a short time but that's not practical. He does the next best thing. In general the antennas I'd expect to perform better do and ones I'd expect to perform worse do.

I don't know why people get so defensive about indoor antennas. It's not controversial to say an indoor antenna is at a distinct disadvantage to an outdoor antenna. That's all I've ever said. I have not ever said you can't receive any stations on an indoor antenna. The FCC assumes an outdoor antenna at 30' for DTV reception. All you're doing by moving an antenna around the house is hoping to stumble upon a spot that has a strong enough signal and low enough multipath to allow the tuner to decode it. This could be easy, difficult or impossible. No moving an antenna around my house is going to receive the Tucson stations. They are simply too weak. OTOH, my two LOS stations can be received with the antenna anywhere in the house.

Chuck
That fact these informative discussions would get real intense with you really does tell a lot. You are looking at this in a very contained and old fashion manner. Antenna is a small piece of the equation to TV reception. You are drilling into a topic in a way that really doesn't matter. All pieces of TV reception technology is changing and improving.

You are right on, that people like me, are moving the indoor antenna around in the house to find that location with enough signal level and minimal destructive interference. There is nothing wrong with that! It's no different then you throw up a bunch of elements on the pole to address multipath and other issues.

Without sharing too much details on IP or being too blunt, I would say your thinking is very dated. The polar plot, debating about lobe and traditional view on dB is old school. Machine learning is happening, everywhere, even in RF. Tuner can learn the interference and still extract signal even in very low SNR conditions that you can't even imagine. Demod will use machine learning to conceal data loss and improve error correction like never before. The point of the industry is better signal extraction using very rudimentary antenna, so the average consumer does not need to build a rooftop that looks like it can communicate with aliens. Your approach to good signal is high SNR/improved reception. New approach is to find that signal buried in all the noise.
 

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You know more than a layman about this but it doesn't mean there aren't others with equal or more knowledge. TV reception is not just about the antenna. The cable, tuner effectiveness, demod efficiencies all contribute. Lobe diagram of an antenna is just one data point, it assume the antenna is placed in one fixed position. With the film based flat antenna, I can affix it to different places and because they are light, I can use putty to secure its base and have n-degree freedom in x,y,z to adjust its placement and compensate for a lot of issues. It's way more than what you can do with outdoor antenna once it's on the pole. Hence all the discussions are about a particular design on elements, number of elements, their placement, reflectors and so on. Because you no longer have the flexibility to move it in x,y,z, so you add more elements to increase ways the signal can be picked up.
I understand what you're saying.... I think. I think you're saying that an indoor antenna can equal an outdoor antenna because of the ability to move it around. As in so many things RF, there may be isolated cases where this is true. I have to ignore those cases because it's like looking for a zebra in a herd of horses. It's a very uncommon experience. Of course tuner/demod characteristics apply but they don't change based on the antenna so they can be ignored. For example, the antenna doesn't determine over what delay times a demod can resynch a multipath signal.

I have to ask...... Have you ever taken a spectrum analyzer and measured the signals coming from a good outdoor antenna and from an indoor flat panel? I don't think you'd be advancing this theory if you had. This is certainly one of the most bizarre theories of reception I've ever heard. If only this was true I wouldn't have to have my TV antennas on my ham radio tower at 65' for decent reception. :)

Chuck
 

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That fact these informative discussions would get real intense with you really does tell a lot. You are looking at this in a very contained and old fashion manner. Antenna is a small piece of the equation to TV reception. You are drilling into a topic in a way that really doesn't matter. All pieces of TV reception technology is changing and improving.

You are right on, that people like me, are moving the indoor antenna around in the house to find that location with enough signal level and minimal destructive interference. There is nothing wrong with that! It's no different then you throw up a bunch of elements on the pole to address multipath and other issues.
I guess you're not reading anything I'm writing because you keep arguing points I'm not disagreeing with.


Without sharing too much details on IP or being too blunt, I would say your thinking is very dated. The polar plot, debating about lobe and traditional view on dB is old school. Machine learning is happening, everywhere, even in RF. Tuner can learn the interference and still extract signal even in very low SNR conditions that you can't even imagine. Demod will use machine learning to conceal data loss and improve error correction like never before. The point of the industry is better signal extraction using very rudimentary antenna, so the average consumer does not need to build a rooftop that looks like it can communicate with aliens. Your approach to good signal is high SNR/improved reception. New approach is to find that signal buried in all the noise.
Maybe you have some future technology running in your house but the rest of us don't. Even ATSC 3.0 isn't going to do any of those things you describe. Maybe those things will become reality someday, but today we still have to deal with adequate SNRs and good antennas. People come on here with real reception problems that need real answers not imaginary technology. Walking around with a flat panel antenna looking for a hot spot is not a real solution for many people.

My experience with extracting signals buried in the noise involves signal averaging and low data rates. If you're aware of better techniques then please enlighten us. I don't think there are any threads on AVS discussing anything like this. You should start one. Right now this sounds like one of those theoretical technologies with no known way to engineer it.

Chuck
 

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I have to ask...... Have you ever taken a spectrum analyzer and measured the signals coming from a good outdoor antenna and from an indoor flat panel? I don't think you'd be advancing this theory if you had. This is certainly one of the most bizarre theories of reception I've ever heard. If only this was true I wouldn't have to have my TV antennas on my ham radio tower at 65' for decent reception. :)

Chuck
Yes I have! My home in Central Valley is a single dwelling, so I can do whatever I want on the roof and I have outdoor antenna on it. It works fairly well in most cases. But I live in the Bay Area for my job and I am been in apartments and condos for many years. For that reason, I tried to find a very reliable indoor solution, since I can't put up an antenna on the roof. With a properly/optimally oriented good indoor antenna, I can get very good readings on spectrum analyzer. I think the traditional approach is just putting antenna somewhere flat and take reading will not always yield good results. Yes, the RX level is a bit lower than outdoor antenna for obvious issues but overall, they are remarkably good.

To streamline my "moving around" process and make it go faster, I wrote scripts to automate the process and it's done with a USB/PCIe tuner card. I have the tool scan a list of channels, of the main VC on a given RF (the highest bandwidth ch), extract some metrics for signal quality readings from the tuner and demod. With this, I move the antenna, run the script, and I get a view of how well the this position works. This allow me to very quickly "fine move" the antenna within the identified "hot spots".
 
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