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You get it after working with it a while, but it would be helpful to have it explained better up front.

For example,
The Read button in ASuite means that ASuite will read whatever configuration the Avant currently has into ASuite.
Selecting Send in ASuite will send whatever configuration is currently showing in ASuite to the Avant.
Open will open a saved configuration from the computer storage location.
Save will save the open configuration in ASuite to computer memory, NOT the Avant.

When you select Adjust, ASuite will check to see if the configuration is different from the Avant unit and if it is, it will update it and then adjust and send that to the Avant. If the configuration is the same, it will adjust and send that to the Avant.

Adjusting the individual RF channels up or down by up to 3 db is like an over ride of the automatic adjustment. ASuite accepts that over ride and sends it immediately to the Avant. If you select Adjust again, that wipes out any over rides. When you over ride a particular channel up or down, ASuite flashes "adjusting" on the screen just like it does when you press the Adjust button. That led me to believe that it was adjusting every channel again but I think it is just sending the over ride to the Avant rather than readjusting everything just because you over rode one channel's setting.

Though there is an Adjust button on the Avant, it is not necessary to use it if you are using the ASuite program which has its own Adjust (virtual) button to select.

ASuite is pretty simple so that after you get used to it, a modern phone is more convenient and plenty good to make any changes without bothering with a laptop or something.

Just some random thoughts on what I think I picked up correctly after working with it a little.
Well in my case I stood on a ladder for eight hours trying to figure out why it wasn't tunning correctly. I was smart enough to know I was doing something wrong, I just didn't know what. Thankfully I found the information I was looking for in another forum. One of the big things I noticed was even with a low power setting I was overdriving a distribution amplifier I have installed in my system. I actually had to research ideal power output levels. I'm certain I knew them at one point in time but I have long forgotten. It turns out this amplifier is really designed to drive large long-distance cable installs as you would have in a small hotel, shared antenna in a condo, that kind of thing. The test output is actually a minus -20db output. It's the output you want for residential installs. So you can really just keep the 75ohm load on the TV output and attach your system to the Test output. At least that is my current understanding. I have one remaining problem to work out. The amplifier has created a multipath problem on one channel. It goes away after sunset but it's there during daylight. As far as I can tell it's amplifying a reflected signal to near the same level as the primary signal. It's causing some breakup problems on a couple of Sony televisions. Other televisions are doing a better job at discriminating against the multipath signal. The channel was working fine prior to installing the amplifier.

Other than those issues it works really well once it is properly setup. By far the best way I have seen to combine multiple antennas onto a single cable.
 

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One more note. Low VHF is very susceptible to any kind of electrical noise. My local PBS is all the way down in channel 4. My antennas are mounted above my wife's craft studio in the attic. The room has LED can lights and when they are turned on some electrical noise is transferred to the coax cable causing breakup on the low VHF PBS channel. I rolled channel 4 up onto channel 34 in the UHF range and it solved the interference problem. Kind of a neat little trick The television display channel remains 13.
 

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One more note. Low VHF is very susceptible to any kind of electrical noise. My local PBS is all the way down in channel 4. My antennas are mounted above my wife's craft studio in the attic. The room has LED can lights and when they are turned on some electrical noise is transferred to the coax cable causing breakup on the low VHF PBS channel. I rolled channel 4 up onto channel 34 in the UHF range and it solved the interference problem. Kind of a neat little trick The television display channel remains 13.
Thank you for sharing that trick regarding low vhf. I have a couple of low vhf channels that are on the edge of coming in. I have lots of led lights and I know they can and do interfere with those channels. I thought all that interference came before the antenna preamp. I will definitely give it a try shifting them to unused uhf channels.

Another interesting thing I found was that the filters can affect adjacent channels. My RF11 and RF12 come from the same direction. I mentioned before in this thread that if I manually boost RF12 by 3db it clears up completely. But I also discovered that the problem is in relation to RF11 because if I cut RF11 by 3db, I get the same effect. Actually just about any combination of 3db difference between the two will clear up the reception of RF12. Kind of funny because RF 12 is actually the stronger signal but it is the only one affected. I tried combining them into one filter too but it doesn't work quite as well.

Also from just a little more use I can confirm that using a phone to tweak the ASuite program is much much faster and easier than a laptop. Highly recommended to get whatever cable is needed to make that happen. In my case, that was a USB-C to Micro USB male to male cable.
 

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Thank you for sharing that trick regarding low vhf. I have a couple of low vhf channels that are on the edge of coming in. I have lots of led lights and I know they can and do interfere with those channels. I thought all that interference came before the antenna preamp. I will definitely give it a try shifting them to unused uhf channels.

Another interesting thing I found was that the filters can affect adjacent channels. My RF11 and RF12 come from the same direction. I mentioned before in this thread that if I manually boost RF12 by 3db it clears up completely. But I also discovered that the problem is in relation to RF11 because if I cut RF11 by 3db, I get the same effect. Actually just about any combination of 3db difference between the two will clear up the reception of RF12. Kind of funny because RF 12 is actually the stronger signal but it is the only one affected. I tried combining them into one filter too but it doesn't work quite as well.

Also from just a little more use I can confirm that using a phone to tweak the ASuite program is much much faster and easier than a laptop. Highly recommended to get whatever cable is needed to make that happen. In my case, that was a USB-C to Micro USB male to male cable.
Yes, the link I shared in one of the above posts over on satellite guys discusses this issue. The problem this amplifier is designed for the European PAL system and adapted for the U.S. European channel bandwidth is 7-8Mhz. The U.S. IS 6Mhz. I was thinking my problem with one channel was multi-path but I’m currently wondering if this may be the cause of the problem.
 

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Yes, the link I shared in one of the above posts over on satellite guys discusses this issue. The problem this amplifier is designed for the European PAL system and adapted for the U.S. European channel bandwidth is 7-8Mhz. The U.S. IS 6Mhz. I was thinking my problem with one channel was multi-path but I’m currently wondering if this may be the cause of the problem.
This is not correct, the Americas version of the Avant X, part number 532180, is designed for US frequencies and channelization. The channel bandwidth is 6MHz, and the center frequencies of the channels are programmed according to US broadcasting allocations. The unit actually adjusts the bandwidth of the filters carefully depending on the programming so as to minimize effects on strictly adjacent channels.
 

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This is not correct, the Americas version of the Avant X, part number 532180, is designed for US frequencies and channelization. The channel bandwidth is 6MHz, and the center frequencies of the channels according to US broadcasting allocations.
Thank you. I stand corrected.
 

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Another interesting thing I found was that the filters can affect adjacent channels. My RF11 and RF12 come from the same direction. I mentioned before in this thread that if I manually boost RF12 by 3db it clears up completely. But I also discovered that the problem is in relation to RF11 because if I cut RF11 by 3db, I get the same effect. Actually just about any combination of 3db difference between the two will clear up the reception of RF12. Kind of funny because RF 12 is actually the stronger signal but it is the only one affected. I tried combining them into one filter too but it doesn't work quite as well.
The selectivity of the Avant's filters is almost 30dB at 1MHz. There's no such thing as an "ideal" infinite attenuation and infinite slope filter in RF electronics. When receiving strictly adjacent channels from the same input, sometimes it's a better solution to filter them in clusters. The Avant can and will filter individual channels, but can also enlarge the filters up to 4 channels wide, adjacent. Depending on the relative levels of the strictly adjacent channels, sometimes performance can be improved using clusters. An spectrum analyzer is typically a good thing to have handy to verify what's best.

Key spec to keep in mind is the Avant is able to correct 60dB between carriers provided the input muxes are between -20dBmV and +40dBmV. In those conditions the unit will be able to filter the muxes and adjust the levels of each to the programmed output level between 30 and 55dBmV. One limitation is strictly adjacent RF channels / muxes in the same input, in that case the maximum difference that the unit can correct is 30dB. That would correspond to two strictly adjacent RF channels being received from the same antenna with a difference over 30dB in power.
 

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This is not correct, the Americas version of the Avant X, part number 532180, is designed for US frequencies and channelization. The channel bandwidth is 6MHz, and the center frequencies of the channels are programmed according to US broadcasting allocations. The unit actually adjusts the bandwidth of the filters carefully depending on the programming so as to minimize effects on strictly adjacent channels.
Then explain these scans that CLEARLY show otherwise! (note the markers tht show the actual bandwidth of that single channel bandpass, not a haystack)

10 0nly ch 21 w markers.png 12 30 & 32 only w markers.png 13 26 & 27 1.5mhz excessive BW.png
 

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Then explain these scans that CLEARLY show otherwise! (note the markers in 2 posts);
www.satelliteguys.us/xen/threads/televes-avant-x-programmable-4-input-distribution-amp.392365/#post-4583279
Bruce, they do not show otherwise. They show, as I said, that there's no such thing as an infinite rejection filter. As explained before, and to you before on our conversations, the limitation for strictly adjacent channels on the same input is 30dB difference.

Below is the single channel filter response of the unit. A different response is applied for strictly adjacent and non strictly adjacent channels.

Adjacent - single channel filter response:
3107156


Non adjacent - single channel filter response:
3107160
 

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My SA TG scans say otherwise. Then how do you explain the results on the Siglent?
What make/model SA was that taken from?

As to my procedure;
1. Set frequency range for the SA,
2, Connect test cables (preferably w/o adapters), then enable the TG and normalize the scan,
3. Clear all channels for input 1 and select the specific channel(s) wanted, no others, lowest output,
4. Connect the Avant-X as one would with any DUT (input 1 to TV or test port out) and set the markers as needed showing the marker table.

Unless someone else can account for the differences in the scans.

(Previous post updated)
 

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Bruce, I cannot speak to what your spectrum analyzer is showing. You can see in the example I posted earlier in this thread how the Avant filters 6 MHz channels. If there is a strong adjacent channel then the output spectrum might show some vestigial extra "shoulders", which is explained as said by the rejection available in the filter, and not a problem for reception.
 

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Hoping to further clarify the filtering questions, here is another example with real signals. I'll just play around with filters on RF33, RF34 and RF35. Please disregard the quality of the spectrum, multi path, fading, etc. This at my desk using a small indoor antenna.

Input spectrum, span 200MHz, centered on RF34:

3107299


Input spectrum, span 20MHz, centered on RF34:

3107302


Input measurements, straight off the antenna, on RF33, RF34, and RF35:

3107303

3107305

3107306


Now I program RF33, RF34 and RF35 on the Avant.

Output spectrum, span 200MHz, centered on RF34, only those three muxes come through:

3107307


Output spectrum, span 20MHz, centered on RF34, after Avant single channel 6MHz filtering:

3107308


Output measurements, after the Avant single channel filtering of those channels, on RF33, RF34, and RF35:

3107310

3107311

3107312


The in/out MER degradation in the Avant is typically <1dB.

Now instead of the three filters I only program one channel each time. Spectrum output, showing the 6MHz filtering. Note some shoulders, due to the bleed of the adjacent channels through the filter slope ([email protected]). As the quality measurements at the output above prove, this is not a problem for decode:

3107313

3107314

3107315


All three muxes at the output, decoding:

3107316

3107317

3107318

3107319

3107321

3107322
 

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Javier;
Those 'off air' readings from your H30Evolution are not the same as results using a SA with a TG. Two completely different animals. The scans you sent to me 2 months ago now seem to be actual RF carriers (haystacks) vs shape factors of the filters which would explain everything.
Wherever those scans came from, ask what equipment was used to generate those results.

A single RF channel off air, not a TG sweep result;
14 20 discone.png
 

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Bruce, those are ATSC carriers in a spectrum analyzer. The filter responses before obviously off a network analyzer. All I’m trying to clarify here is the filters in the Avant are 6MHz wide and 100% designed for US use. They are actually optimized dynamically for adjacent or non adjacent cases. I’d appreciate if you would correct assertions stating otherwise that might confuse folks.
 

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I’m punting after spending three days on a ladder trying to get this amplifier to work in my situation. It seems to work pretty well if you have strong signals with exceptions. I do not own a spectrum analyzer so my conclusions are indirect.

Problems I have observed:

1. One channel that under normal circumstances I receive without issue now appears to have a multi path issue. Once it goes through this amplifier it appears a reflected signal is being amplified to a level that causes problems with several television tuners.

2. Edge signals that I can normally tune are unusable.

3. I have noticed monitoring signal strength that strong signals bleed over onto empty filtered channels in several instances. Maybe my multi-path problem? Maybe channel bleed?

I have tried all matter of rolling channels to isolate the problem channels from adjacent channels when there is a large signal strength difference hoping to solve issues with minimal success. It did work in once instance, but not others.

Uncle
 

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Realizing that different spectrum analyzer equipment was used for each of the following images:

Then explain these scans that CLEARLY show otherwise! (note the markers;)



Below is the single channel filter response of the unit. A different response is applied for strictly adjacent and non strictly adjacent channels.
Non adjacent - single channel filter response:
View attachment 3107160



-------------------------

The above images appear that they could be compared, as they show bandwidths greater than 6 MHz DTV channel..

However, Videobruce has not posted an image that might correspond to the 2nd TelevesTech image:

That 2nd TelevesTech image shows a narrower 6 MHz wide filter tightly fitting a DTV channel, indicated as;

Adjacent - single channel filter response

Videobruce, can you produce images that correspond to both?

Videobruce, does your Avant-X not have the two bandwidths available?

Adjacent Single Channel response and Non-Adjacent Single Channel response

If your Avant-X cannot produce an adjacent single-response that corresponds to TelevesTech's narrowband image, then maybe there is a problem with your Avant-X.

.
 

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One more note. Low VHF is very susceptible to any kind of electrical noise. My local PBS is all the way down in channel 4. My antennas are mounted above my wife's craft studio in the attic. The room has LED can lights and when they are turned on some electrical noise is transferred to the coax cable causing breakup on the low VHF PBS channel. I rolled channel 4 up onto channel 34 in the UHF range and it solved the interference problem. Kind of a neat little trick The television display channel remains 13.
This is interesting because it's still RF Channel 4 from the Antenna, built in amp or not, through the coax all the way to the Avant X.
 

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tripelo;
That scan he is showing is a ATSC "haystack" the actual signal from a station, NOT a scan of one of the units 'filters' using the SA's tracking generator option. HUGE difference to anyone that understands the difference!

BTW, it was returned some time back since my existing system with the separate traps worked (for the most part) their's did not even with my traps.
 
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