Do I Have 5G (or Newer) Interference?

[cyberham]

I've never knowingly had 5G interference. But now...maybe 5G or something newer.

See image below. About every 10 seconds, only on 4120 V 30000, a perfectly clear picture from a strong transponder changes to below for maybe one second. Then the clear picture returns. This continues indefinitely. Other transponders on this same satellite don't have this symptom. The symptom makes the channel unwatchable.

I use the Titanium C1-PLL LNBF with no 5G filtering (since I've never needed it!). Research indicates that 5G coverage is in my area. See the second image below which is what my own mobile phone shows. There is a "6" in one of the network signal icons.

What disease have I got?

5G Interference Candidate:


Icons on my Mobile Phone:

 

[comfortably_numb]

I've never knowingly had 5G interference. But now...maybe 5G or something newer.

See image below. About every 10 seconds, only on 4120 V 30000, a perfectly clear picture from a strong transponder changes to below for maybe one second. Then the clear picture returns. This continues indefinitely. Other transponders on this same satellite don't have this symptom. The symptom makes the channel unwatchable.

I use the Titanium C1-PLL LNBF with no 5G filtering (since I've never needed it!). Research indicates that 5G coverage is in my area. See the second image below which is what my own mobile phone shows. There is a "6" in one of the network signal icons.

What disease have I got?

5G Interference Candidate:
View attachment 194020

Icons on my Mobile Phone:
View attachment 194022

Are you close to a cell tower? Maybe they recently lit up a band that causes interference. Happened to me. Even with the special filtering LNB's, 5G knocked out everything below 4000.

 

[Titanium]

Your description of reoccurring signal corruption is likely due to 5G interference. The Signal Quality reading may appear to be good for a period of time until too many signal errors accumulate and the Forward Error Correction is unable to fill in for the missing or corrupted data in the transport stream. When adequate uncorrupted data is once again collected, the image (and / or audio) will again decode.

 

[cyberham]

Are you close to a cell tower? Maybe they recently lit up a band that causes interference. Happened to me. Even with the special filtering LNB's, 5G knocked out everything below 4000.

Having discovered the cell phone tower tool online, I see I have many 4G cells all over my neighbourhood. In fact, there's one right across the street that uses 1900 and 2100 MHz 4G. But the nearest 5G is probably 10 miles away and it uses 600 and 1900 MHz.

I found another 5G tower in town about 20 miles away that operates on 3500 MHz.

 

[Titanium]

Currently, only N77 and N78 band 5G signals transmitted in C-band (3400-3850 MHz) will interfere with your C-band reception. 5G and 4G transmissions in the other bands (I.E. 600, 1900, 2100 MHz, etc) do not interfere with C-band reception.

A cheap TinySA Ultra www.amazon.com/Upgraded-TinySA-Spectrum-Frequency-Generator/dp/B0BBGK9QJB or any satellite meter with spectrum display will show the presence of interferring carriers in the C-band frequency range.

 

[cyberham]

As far as the map shows, the closest 5G on 3500 MHz is pretty far away. But maps may be out of date. This interference just started this week. So it could be a new cell site turned up.

 

[cyberham]

Currently, only N77 and N78 band 5G signals transmitted in C-band (3400-3850 MHz) will interfere with your C-band reception. 5G and 4G transmissions in the other bands (I.E. 600, 1900, 2100 MHz, etc) do not interfere with C-band reception.

A cheap TinySA Ultra www.amazon.com/Upgraded-TinySA-Spectrum-Frequency-Generator/dp/B0BBGK9QJB or any satellite meter with spectrum display will show the presence of interfering carriers in the C-band frequency range.

Those devices are good for checking amateur antennas too.

I notice there doesn't seem to be interference on 4040 V 30000 or 4060 H 29268 on the same satellite. I might have expected 5G to interfere with most transponders. I had wondered about interference from 4120 H 30000 on the adjacent satellite but it's not new. Something seems to have changed just in the past few days.

 

[one_db_compression]

As far as the map shows, the closest 5G on 3500 MHz is pretty far away. But maps may be out of date. This interference just started this week. So it could be a new cell site turned up.

It also conceivable that you are getting skip across the strait from Vancouver Island. There are some interesting propagation modes that the telcos and the electric utility have at various times on their microwave links between the island and the mainland, resulting in both major constructive and destructive self-interference. If the effects on your satellite reception are inconsistent, I wouldn't rule this out. One massive MIMO shooting out over the water under the right conditions could lead to a bad day.

Everyone else's mileage may vary.

 

[cyberham]

It also conceivable that you are getting skip across the strait from Vancouver Island....

I did think about this. VI is straight across the water and not so far. Not much farther in fact than our local town and no obstacles. If this was the source of interference then it may be temporary and may disappear when conditions change.

Probably just coincidental, but the UHF OTA TV (423 MHz) that I receive is very strong these days peaking at 22 dB for the METV mux from 70 miles away in the islands of Washington state.

 

[Titanium]

I notice there doesn't seem to be interference on 4040 V 30000 or 4060 H 29268 on the same satellite. I might have expected 5G to interfere with most transponders.

It is all about SNR (Signal to Noise Ratio) and the FEC (Forward Error Correction) available to replace the corrupted data in the transport streams. Many hobbyist assume that the 5G interference is overlapping or on top of the target transponder frequency. In the 4000 - 4200 transponder frequency range used by satellites targeting North America, 5G is often transmitted adjacent to the transponder frequency (up to 3980 MHz) and may fall within the band pass of the LNB (I.E. C1PLL with band pass 3800 - 4200 MHz). The strong Interfering 5g carriers received within the band pass range affects the gain control of the entire BLOCK (LNB = Low Noise Block) of frequencies. Transponders with a high SNR and forgiving FEC rates may not be affected, while signals with lower SNR and an aggressive FEC rates are affected.

To prevent strong terrestrial carriers from overloading the LNB amplifier's gain, we use steep filters to eliminate or attenuate frequencies above and/or below the range for desired transponder frequencies that we wish to receive.

Tropospheric ducting is very common with temperature inversions and frequently occur in the summer months along the Pacific coast. While we are more aware of tropo openings on TV / Radio broadcast and amateur radio, 3 GHz can also be affected. Here is a tool that I often reference when working amateur radio contacts via tropo openings. www.dxinfocentre.com/tropo_wam.html

 

[cyberham]

I have been watching for about an hour and I see no interference today at all. For the last several days, there was continuous interference on one channel. Maybe the tropo has ended. I can hope so.

 

[shopman]

I have been watching for about an hour and I see no interference today at all. For the last several days, there was continuous interference on one channel. Maybe the tropo has ended. I can hope so.

If that's the satellite I think it is, the problem was with the stream and not your reception. It's been corrected, for now, but I wouldn't be surprised if it returns again in the near future.

 

[cyberham]

If that's the satellite I think it is...

Really! 123W?

 

[shopman]

Really! 123W?

Yep. I saw the same thing and verified integrity by examining the transponder on a spectrum analyzer. Looked beautiful with no terrestrial or adjacent satellite interference. Then I checked the live log and saw what was going on.

 

[cyberham]

Yep. I saw the same thing and verified integrity by examining the transponder on a spectrum analyzer. Looked beautiful with no terrestrial or adjacent satellite interference. Then I checked the live log and saw what was going on.

I saw a little "interference" today but the transponder was mostly clean.