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How can I know if my signals are within the input range requirement of -20 to 40dBmV?
 

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How can I know if my signals are within the input range requirement of -20 to 40dBmV?
The first thing to do is look at your signal report. I did a sample report near Ayer's Cliff Elementary School:
RabbitEars.Info

the report comes up with field strength units, but you can change that to dBmV by selecting that units in the report:
RabbitEars.Info

To the dBmV values in your report you can add antenna gain and preamp gain.

The most accurate way to know the strength or your signals is to use a signal level meter, but they are expensive. The reading on the top scale is -10 dBmV:

ThorCH3AntSNR15SS.jpg


There are less expensive ways to estimate the strength or your signals. The signal meters in TVs just use a relative scale, but you need absolute values. I can continue if you want me to.
 

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Rabbit73, thank you very much for all this great information. I assume that signal values in Rabbitears would be affected up or down by the type of antenna used or if I use a preamp. Am I correct?
 

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Just to be clear, the Avant X ensures that is able to adjust each individual carrier to the desired programmed level as long as the particular RF channel of interest is between -20dBmV and 40dBmV at its input. The unit will run out of its filter gain range for multiplexes outside of that window.
 

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Rabbit73, thank you very much for all this great information. I assume that signal values in Rabbitears would be affected up or down by the type of antenna used or if I use a preamp. Am I correct?
Yes, that is correct. The software, called FCC TVStudy, that is used to generate the reports gives the field strength of a signal just before it touches the antenna in dBuV/m (dB microvolts per meter), so it doesn't know anything about your antenna gain or a preamp. The report also allows you to list the strength of the signals in your report using other units such as dBm, dBuV, and dBmV. All of those are units of power that would be coming out of your antenna terminals, so you are free to add the gain of your antenna and the gain of a preamp, if used.

When you select other units, the report software makes the conversion for you. However, forum member Trip, who created the rabbiters.info Signal Search Map, is the webmaster for rabbitears.info and an employee of the FCC, has added negative correction factors for the VHF channels to allow for the higher noise levels on VHF. That is why you see VHF signals ranked slightly lower than their Signal Margin would indicate.

I suggested that you start with using dBmV values in your report because Televes has indicated the effective operating range of the Avant X is between -20dBmV and +40dBmV at its input, which is a 60 dB range.

You can do a report for your actual location here (I use coordinates):
RabbitEars.Info

However, actual signals coming out of your antenna, allowing for antenna gain and a preamp, might be quite different than listed in your report because of other factors like trees or a building in the signal path. The report assumes that your antenna will be outside and in the clear.

If you want me to teach you some inexpensive ways to estimate the strength of an actual signal, I can do that, but it will be a long post.
 
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Yes, that is correct. The software, called FCC TVStudy, that is used to generate the reports gives the field strength of a signal just before it touches the antenna in dBuV/m (dB microvolts per meter), so it doesn't know anything about your antenna gain or a preamp. The report also allows you to list the strength of the signals in your report using other units such as dBm, dBuV, and dBmV. All of those are units of power that would be coming out of your antenna terminals, so you are free to add the gain of your antenna and the gain of a preamp, if used.

When you select other units, the report software makes the conversion for you. However, forum member Trip, who created the rabbiters.info Signal Search Map, is the webmaster for rabbitears.info and an employee of the FCC, has added negative correction factors for the VHF channels to allow for the higher noise levels on VHF. That is why you see VHF signals ranked slightly lower than their Signal Margin would indicate.

I suggested that you start with using dBmV values in your report because Televes has indicated the effective operating range of the Avant X is between -20dBmV and +40dBmV at its input, which is a 60 dB range.

You can do a report for your actual location here (I use coordinates):
RabbitEars.Info

However, actual signals coming out of your antenna, allowing for antenna gain and a preamp, might be quite different than listed in your report because of other factors like trees or a building in the signal path. The report assumes that your antenna will be outside and in the clear.

If you want me to teach you some inexpensive ways to estimate the strength of an actual signal, I can do that, but it will be a long post.

Rabbit, I think that's a great information. Have you ever posted before how to estimate signal strength inexpensively? That would be a great thread all by itself.
 

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Rabbit, I think that's a great information. Have you ever posted before how to estimate signal strength inexpensively? That would be a great thread all by itself.
I did a short version on AVS and a long version on the TVFool forum
Using an Attenuator to Measure the Strength of a Digital TV Signal, Part 2
page four of this thread
OTA recommendations 31-Aug-2020
The thread is in my username because the poster (verder) asking the questions hadn't been approved yet; I was posting his questions from PMs.

I also gave a short version to you in a recent PM.

The last time I checked the rules for this forum, I'm not allowed to post an active link to another forum.
 
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Thanks Rabbit. I remember when you had to post for me too. It took over two months for TV Fool to approve me. By that time I'd already had my antenna setup done.
I'm really sad about TV fool.
 

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If anyone is interested in this I have one I will sell for the $399 I paid for it, including shipping. It is brand new in box never used. I’m not going to be able to erect the multiple antennas I would need to make it worthwhile for me. This is the US version and I’m located in the US.
 

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If anyone is interested in this I have one I will sell for the $399 I paid for it, including shipping. It is brand new in box never used. I’m not going to be able to erect the multiple antennas I would need to make it worthwhile for me. This is the US version and I’m located in the US.
New user limitation won't let me reply 'yes' to pm.
 

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I bought an Avant X from Ness Electronics Online Store and tested it a bit last night. Here are a few quick observation/instructions.

Overall, I like it a lot so far, once you figure out how to use it. Instructions are in Spanish/English but leave out some details, like actually how to set it up.

I used ASuite on my Android phone to set up. The USB adapter that came with the device is an OTG adapter that is meant to connect to your phone/tablet, NOT the Avant X, even though the port fits. It's the USB micro B that many phones used to have. If your phone has USB C, you will need a USB C OTG adapter and then a regular USB A to USB micro B cord. Or use the Windows version with a USB A to USB micro B cord. (I didn't try the Windows program.)

I found some YouTube videos in Spanish that showed an Avant X automatically scanning for frequencies, but I could not figure out how to get mine to do that. Maybe only certain models do that? Anyway, I had to manually add channels in ASuite. (Chiwaukee mentioned this in post #32.)

This means, if new frequencies become available in your area, a rescan on your TV (when connected through the Avant X) will not find them! You'll need to bypass it, scan on your TV, take note of new frequencies, and reprogram the Avant X.

Televes calls this a "programmable multiband amplifier," in other words, like a digital equalizer for TV frequencies. :)

The same common knowledge for amplifiers/boosters applies to the Avant X, but there's more flexibility because each frequency can have a separate level. So to reiterate some of those rules:

An amplifier cannot magically make a frequency that is too weak usable. It can boost a weak but clean signal to overcome losses between your antenna and TV. Noise is still an important factor. Example, there is one VHF-HI frequency that came in sporadically at about signal quality 27-28 on my TV without the Avant X, that would not come in at all when the Avant X boosted that frequency.

Other frequencies my TV saw as signal quality 35-40-ish without the AvantX, were very watchable when boosted.

Signal level does not equal signal quality. The Avant X adjusted the level of all my frequencies to be the same, but the weaker stations still showed a slightly lower signal quality number on my TV. Just like a regular booster, the noise is boosted along with the desired signal.

The biggest advantage, in my opinion, is the ability to boost weak-but-clean frequencies without overboosting close-and-strong frequencies. (Combining multiple antennas pointed different directions is also very nice, but I'm only using one antenna at the moment.)

My advice for adjusting output level.

On the main "page" in ASuite is the output level. Default is 55. If you slide over to actual frequencies you can adjust each frequency up or down by 3. The per-frequency adjustment is probably not that important unless you are fine-tuning a problem channel, but again, level does not equal quality.

Once programmed and connected to your TV, tune your TV to the strongest channel (the strongest without amplification.) Bring up signal quality monitor, however your TV does this.

If the strongest channel shows signal quality 100, don't believe it. It may be over-amplified. At least, on my TV, it showed 100 for my strongest channel, but it broke up a lot. Reduce the output level on the main ASuite page and send it to the Avant X until your TV shows mid-90's for signal quality on your strongest frequency. Then check the other frequencies. For me, weaker frequencies were in the 80's which is still very high.

You may be fine after this, or you might want to try adjusting weak frequencies higher. But again, strength is not quality, so adjusting individual frequency levels farther than the default balancing may or may not help.

If, after setting up the Avant X, you are going add a splitter to multiple devices, repeat the above, watching signal quality on all the connected tuners.

Anyway, this is just after one night of testing it out. I record TV with a quad tuner in a MythTV box, so after a while I'll know better how much the Avant X helps. Currently, recordings on several channels "break up" frequently.
 

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once you figure out how to use it. Instructions are in Spanish/English but leave out some details, like actually how to set it up.
some YouTube videos in Spanish that showed an Avant X automatically scanning for frequencies, but I could not figure out how to get mine to do that. Maybe only certain models do that? Anyway, I had to manually add channels in ASuite.

in ASuite is the output level. Default is 55. If you slide over to actual frequencies you can adjust each frequency up or down by 3.
They seem to be taking after the Chinese, very little, if any decent manuals. Best example is this 'quick start guide which I now find out is the 'manual'. :rolleyes:

The "up or down by 3". is that 3db or what?
 

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After the automatic level adjustment has been completed, the "adjust" tab allows for a +/-3dB gain adjustment of each individual filter.

Like any other processing device the Avant has certain dynamic range per filter. It is able to adjust and equalize incoming signals between -20dBmV to 40dBmV to a programmed output level between 30dBmV and 55dBmV (or 75dB margin). Outside of that input range there will be cases where the agile filter programmed for a particular channel or cluster may not have enough gain or attenuation available to bring the channel to the programmed output level.

It is possible in some scenarios that a fringe signal which is able to marginally be decoded when fed directly to a tuner may perform worse after processing, by the Avant or other device. This is entirely normal as indicated by a user earlier in this thread. Any RF processing of a very fringe signal is not going to improve it's quality. The main advantage of the Avant is to be able to individually process channels coming from up to four different antennas/markets/directions and provide a way to distribute them on a single wire combining them filtered, well balanced and amplified, avoiding co-channel interference and multipath, for further distribution. This is not possible by directly combining the antennas or without an elaborate processing headend. Like in any processing system, the incoming signals need to meet certain specifications.

It is important to note that during the adjustment process the main TV+CATV output be loaded with a 75 ohm termination load. The reason for this is that when the unit is adjusting the gain of each individual programmed filter, it reads the level on that output, and if not terminated, there will be a mismatch and the read value won't be correct, and neither will the filter adjustment as a consequence. During that process, the input signals need to be connected as well, of course. Best practices dictate for any unused ports to be terminated anyway.

Another common configuration mistake is for users to program filters in empty channel locations "just in case" something comes in. This should not be done because the Avant X will maximize the gain of that filter during adjustment, only to add noise to the aggregated signal. The Avant X is intended to acquire existing signals from a set of antennas, and process, balance, and combine them in the best way possible on a compact headend solution. The Avant features an FM input that will be adjusted according to the output level programmed in the unit, and a CATV mix input for when it is used to inject OTA channels in an existing cable distribution.
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Hope some of this helps answer some of the questions.
 

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I found some YouTube videos in Spanish that showed an Avant X automatically scanning for frequencies, but I could not figure out how to get mine to do that. Maybe only certain models do that? Anyway, I had to manually add channels in ASuite. (Chiwaukee mentioned this in post #32.)
The North America version of the Avant X, P/N 532180, does not have automatic channel scan. It does require to manually program the channels or clusters desired per input on A-Suite or using the Televes handheld programmer.

This means, if new frequencies become available in your area, a rescan on your TV (when connected through the Avant X) will not find them! You'll need to bypass it, scan on your TV, take note of new frequencies, and reprogram the Avant X.
Once the unit has been programmed and adjusted, it will establish a set of filters per input, and reject everything else, so if a new multiplex becomes available, yes, a filter will need to be programmed for that channel on the corresponding input, the unit readjusted, and any downstream tuners to be re-scanned if needed.

Televes calls this a "programmable multiband amplifier," in other words, like a digital equalizer for TV frequencies. :)
In a nutshell the Avant X is a filter > processor > amplifier. It allows the filtering of up to 32 individual channels or clusters coming off of four different antennas, and processing them to any frequencies desired, equalize the levels, and provide a programmed output level which is maintained over time. There are a number of applications for this feature set, for example to be able to ingest, filter, equalize and combine content from different markets/antennas in a clean fashion over a single coax feed. Since the Avant also allows to frequency-shift incoming carriers, an operator can receive same RF channels from different markets without co-channel interference.

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An amplifier cannot magically make a frequency that is too weak usable. It can boost a weak but clean signal to overcome losses between your antenna and TV. Noise is still an important factor. Example, there is one VHF-HI frequency that came in sporadically at about signal quality 27-28 on my TV without the Avant X, that would not come in at all when the Avant X boosted that frequency.

Other frequencies my TV saw as signal quality 35-40-ish without the AvantX, were very watchable when boosted.
Hard to tell what TV quality indicators mean. The MER in/out degradation in a channel through the Avant is typically less than 1dB.

On the main "page" in ASuite is the output level. Default is 55. If you slide over to actual frequencies you can adjust each frequency up or down by 3. The per-frequency adjustment is probably not that important unless you are fine-tuning a problem channel, but again, level does not equal quality.

Once programmed and connected to your TV, tune your TV to the strongest channel (the strongest without amplification.) Bring up signal quality monitor, however your TV does this.

If the strongest channel shows signal quality 100, don't believe it. It may be over-amplified. At least, on my TV, it showed 100 for my strongest channel, but it broke up a lot. Reduce the output level on the main ASuite page and send it to the Avant X until your TV shows mid-90's for signal quality on your strongest frequency. Then check the other frequencies. For me, weaker frequencies were in the 80's which is still very high.

You may be fine after this, or you might want to try adjusting weak frequencies higher. But again, strength is not quality, so adjusting individual frequency levels farther than the default balancing may or may not help.

If, after setting up the Avant X, you are going add a splitter to multiple devices, repeat the above, watching signal quality on all the connected tuners.
The output level in the Avant X is programmable between 30dBmV and 55dBmV, and also a slope setting is available for larger cable distributions, such an MDU for example. The higher values will likely be too strong in many residential settings, so the Avant also features a -20dB output, on which the programmed value will range between 10dBmV and 35dBmV. So in practice, the output level can be adjusted between 10dBmV and 55dBmV, enough range to cover a wide variety of distribution scenarios.

Hopes this clarifies some questions.
 

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Practical example, customer from Prescott, AZ:

I see, you have Prescott at 194º and Flagstaff at 59ª and a number of RF channels (14, 19, 30) being used from each location. What typically one would do in this situation is point a directional antenna to each market, and connect each antenna to a different input in the Avant, then select the RF channels that you want to receive from each of the inputs in the Avant. So just for the sake of argument, you could point an antenna to Prescott and get 14 and 19 from there (because the signal is better in that direction) and another antenna from Flagstaff and get 30 from there (again, because 30 comes better from there). The Avant will filter each of those RF channels from each input and remove everything else (so you don’t get co-channel interference from the unwanted channel in each direction), and provide them to you in the output well balanced and adjusted. This is the case assuming you only want to receive one of those specific channels from each direction. More below.

The other option is you want to receive 14, 19 and 30 from BOTH directions, because the content is different. If that’s the case, you can program 14, 19, 30 on both inputs of the avant, coming from both feeds, and the avant will filter them from each antenna. Now what you want to do is to frequency-shift one of the copies to a different frequency so that when combining them in the output, they don’t sit on top of each other. The avant will allow you to do that. You could program as follows:

ANTENNA 1 (PRESCOTT)
RF 14 IN - to - RF 20 OUT
RF 19 IN - to - RF 21 OUT
RF 30 IN - to - RF 22 OUT

ANTENNA 2 (FLAGSTAFF)
RF 14 IN - to - RF 23 OUT
RF 19 IN - to - RF 24 OUT
RF 30 IN - to - RF 25 OUT

Or any other mapping that you want, like leaving the ones from one antenna untouched and putting the copy right behind them, as follows:

ANTENNA 1 (PRESCOTT)
RF 14 IN - to - RF 14 OUT
RF 19 IN - to - RF 19 OUT
RF 30 IN - to - RF 30 OUT

ANTENNA 2 (FLAGSTAFF)
RF 14 IN - to - RF 15 OUT
RF 19 IN - to - RF 20 OUT
RF 30 IN - to - RF 31 OUT

It doesn’t really matter, it will depend on what you’re receiving from all the directions you are receiving signals from. What counts is the Avant will allow you to cherry pick the RF channels you want to receive from each direction, and only those, and arrange them in the output however you see fit. While also adjusting them for power at the same time.
 

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Regarding reassigning stations to other physical channel numbers.
I see a possible problem regarding devices when using outside party 'Guide data'. Namely TiVo recorders. Rovi (that owns TiVo and also supplies the data for their 'Guide') has their 'system' programmed to expect stations to be on predefined physical channel numbers. During the 'repack' when everything was in 'disorder', stations that 'moved' earlier than expected the 'Guide' data did not show under the new physical channel number. It still did show on the old allocation, but not under the new assignment.

IOW's you could not record a program on that channel without manually entering in the channel number, start & stop times, AKA 'VCR' style. They changed their regional data to now include stations in the market you are in. Of course there are many mistakes in this and many stations would be out of range for most owners given the lack of decent outdoor antenna(s) or just being in a poor location. I guess to make things easier for 'Joe SixPack' where an antenna scan almost isn't necessary (but still required).

Moving the station to a different physical channel number I would expect would do the same thing. Hope that last part made sense. ;)
 
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