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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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