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Thank you jruano. Would this device help with this situation: receiving a distant station on channel 20 stuck between two strong locals in the same direction on channels 19 and 21? Sometimes, my TV tuner cannot see channel 20 because it is overloaded by channels 19 and 21.

When stations switch to ATSC 3.0, will it be transparent for the Advent X? No need to change anything (besides the TV set)?

Also, this question for Chiwaukee. When you changed the output channels with your second antenna, did this affect the PSIP channels? In other words, with your setup with two antennas getting the same channels, did you get, say, two channels 36.1, two channels 58.1, etc. on your TV set?

Thank you !
 

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Thank you jruano. Would this device help with this situation: receiving a distant station on channel 20 stuck between two strong locals in the same direction on channels 19 and 21? Sometimes, my TV tuner cannot see channel 20 because it is overloaded by channels 19 and 21.

When stations switch to ATSC 3.0, will it be transparent for the Advent X? No need to change anything (besides the TV set)?

Also, this question for Chiwaukee. When you changed the output channels with your second antenna, did this affect the PSIP channels? In other words, with your setup with two antennas getting the same channels, did you get, say, two channels 36.1, two channels 58.1, etc. on your TV set?

Thank you !
FIrst question: Absolutely, you can filter out just channel 20 in that direction and remove 19 and 21. A customer recently posted this on a Facebook group:

“To everyone I've ever scolded for saying you can't mix the outputs of antennas, I take it back. You can, with a Televes Avant X processor.

My Avant X arrived on Saturday morning and I got a quick chance to experiment with it over the weekend. Its claim to fame is that it can selectively pass individual or groups of sequential channels from up to four antennas. Basically it allows you to say I want this channel from this antenna and that channel from that antenna. It prevents you from having to passively mix antennas where the results are almost always destructive.

As a quick test, I put my Philadelphia antenna on input 1 of the Avant X. I have line-of-sight to Philadelphia. The signals are very strong. I programmed the Avant X to pass channels 31 and 33 from the Philly antenna. At that point, nothing but those two signals showed up on a spectrum analyser coming out of the Avant X. So far so good.

I then connected my Harrisburg, PA antenna to input 2 and programmed the Avant X to pass only channel 32. Channel 32 from Harrisburg is substantially weaker than Philly and its noise margin is just good enough to get a solid picture when connected to a TV. The Avant X completely removed Philly channels 31 and 33 from the Harrisburg antenna and was able to pass channel 32 which sits between those two Philly channels that are at least 30dB stronger. That's incredible. A multi-thousand dollar filter network could not do that.

The end result was that I got channels 31, 32 and 33 out of the Avant X from two different antennas at equalized power levels. What was even more amazing was that the Harrisburg station which was already weak with a low margin was able to be passed through the Avant X and remain usable as there was no margin for further degradation.

Suffice to say, I am thoroughly impressed. This device can completely obsolete your rotator. Point an individual antenna at each city and properly mix all the channels. You'll be able to do one channel scan on your receiver and grab all your receivable stations.

Once I get a chance to put more antennas on the Avant X and do more testing, I will post some spectrum analyser grabs and more detailed results.

Wow.”

Second question: RF channels don‘t change with ATSC 3.0, transparent.

Third question: The Avant filters, adjusts level and frequency-shifts doing digital processing but does not demodulate the stream, no changes to PSIP info.

Hope this clarifies
 

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Thank you very much for your crystal-clear responses. This devices looks really amazing.
 

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But for Yagi's example of channels in one direction with one antenna, even if you disable rf19 and rf21 on the device, their interference would still exist on rf20, right? This device appears to be for combining multiple antennas aimed in different directions into one output cable for one tuner, instead of using multiple cables/tuners or using one cable/tuner and having to deal with the negative effects of using a simple combiner/splitter-in-reverse.
 
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Is there any good source in the US to buy that version here without having to import? This sounds like just what I need for my area.
 

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But for Yagi's example of channels in one direction with one antenna, even if you disable rf19 and rf21 on the device, their interference would still exist on rf20, right? This device appears to be for combining multiple antennas aimed in different directions into one output cable for one tuner, instead of using multiple cables/tuners or using one cable/tuner and having to deal with the negative effects of using a simple combiner/splitter-in-reverse.
In reality to the extent that those three RF muxes are inside the input range of -20dBmV to 40dBmV of the unit, the Avant will filter them independently and adjust them to the desired output level. That the tuner cannot make the distant channel with those two adjacent channels doesn’t mean it can’t be filtered and adjusted, but it will depend on levels as to how high it can be brought up. It is the same case that was described on a previous post by that customer.

The typical use of the Avant is indeed combining different over-the-air feeds avoiding co-channel interference, providing one combined feed with all the carriers correctly filtered and balanced.
 

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Is there any good source in the US to buy that version here without having to import? This sounds like just what I need for my area.
All typical CATV/SMATV/MATV distributors in the US should have access to it.
 

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The possibilities are endless! Talk about greed, I'm thinking about adding a fourth array to my Avant X now that I know how well it works. This tool / device is an enabler for my antenna addiction.

I am planning a antenna shootout this weekend between the HDB91X, 91XG and the Televes DAT BOSS LR...

The winner will go up the tall mast for further testing. Not to say the others wouldn't, but for now I just want to do some off the ladder testing 😉.
How many miles/kilometers away are you able to receive? My problem is I live exactly 80 kilometers away from towers in each direction, just out of the range of reliable reception
 

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Discussion Starter #29
How many miles/kilometers away are you able to receive? My problem is I live exactly 80 kilometers away from towers in each direction, just out of the range of reliable reception
Tvmaster. I'm sorry I had abandoned this thread and didn't realize you were asking me a question.

I have two markets. Most likely an ideal situation. Milwaukee is 49 miles north, Chicago is 39 to 40 miles south depending on which transmitter, the John Hancock or the Sears Tower. It will always be the Sears Tower to me.

Signal strengths are mostly 70 to 90% from Milwaukee and and Chicago 85% to 97% with my long Yagi's.

Signal strength has never been an issue for me and I used the rotator solution for years.

When I combined arrays is when I found out how combining ruins your signals. Sure I kept the strongest stations from both markets but lost any of the lower stations do to multipath, interference Etc.

Instead of rotating the rescanning we went with the two tuner solution. It's probably okay if you have a 1 TV room. And somebody who is very savvy with all the different remotes. No more of that anymore. Now just turn the TV on and use it and accept your hundred plus channels.

Unfortunately, I know that's not your situation, but you asked me about mine.

You need to go to your local reception area and post the question to see what others are using.

You will most likely need:
The largest antennas you can find.
Exercise all low loss techniques like RG11 NO three or five-way combiners.
Low noise Pre-amps
Very good quality TV tuner.
The Avant X if you do go to combine.
 
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