5G Interference on all Transponders

It doesn't look like they'll arrive today. Tracking shows them to still be in Omaha. Typical USPS performance.
 
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I'm about ready for a Blue version. Nothing I watch now is under 4GHz except for the FTA Weather Channel on 127w.

I'd still be willing to take a chance on your free one listed on the classified page. Just to trial and error things a bit. I don't have a TinySA that covers above the 900mhz band.
Me too Captian. I hope Brian decides to put them out this fall,,,soon !!!!!
 
I got my new LNBFs today. I've only installed one. It appears that anything below 4 GHz gets wiped out. I'm trying to watch 3830H15000-3/4 DVB2 (Azteca mux) on 113W. The signal level goes up and down. When it's up I get about 12.5 dB C/N. Then it drops to zero. Signals above 4 GHz are OK - both horizontal and vertical.
 
As you are a long-time customer, I will offer to reimburse you for your purchase. Please donate the open unit to another SatelliteGuys member and we will make arrangements to return the unused unit. It is not our policy to return and refund filtering LNBFs after testing, but I had encouraged you to purchase... Yes, a good reminder that we should have first determined what your were up against before playing "pin the tail on the donkey" with equipment! LOL

The C138 and C238 LNBFs do not attenuate 3820 - 4200MHz. It appears that you either have extremely strong 5G or they have received permission to test the full N77 upper band range in your area. A spectrum analyzer could determine the source and frequency of the interference. It may be necessary to physically place a barrier (rf fence or structure) between your dish and the source and/or use mechanical filtration in the waveguide between a feedhorn and LNB.
 
As you are a long-time customer, I will offer to reimburse you for your purchase. Please donate the open unit to another SatelliteGuys member and we will make arrangements to return the unused unit. It is not our policy to return and refund filtering LNBFs after testing, but I had encouraged you to purchase... Yes, a good reminder that we should have first determined what your were up against before playing "pin the tail on the donkey" with equipment! LOL
Well, since I don't have access to a microwave spectrum analyzer I'm somewhat limited. I think my XR-3 has a spectrum analyzer though. I've never used that function before though. Not a big deal because the cost of these LNBFs are "petty cash" for me.
The C138 and C238 LNBFs do not attenuate 3820 - 4200MHz. It appears that you either have extremely strong 5G or they have received permission to test the full N77 upper band range in your area. A spectrum analyzer could determine the source and frequency of the interference. It may be necessary to physically place a barrier (rf fence or structure) between your dish and the source and/or use mechanical filtration in the waveguide between a feedhorn and LNB.
I don't know if a regular LNB will get the job done. As we know, if the interference falls within the passband then it's "game over". I don't know if I can install an RF fence that'll get the job done either. I probably should have put my new shed in the SW corner of my lot but then it'll be sitting on top of several utilities including the buried power line. I don't know who is running 5G here but it's likely to be Verizon. I don't know if they'll give me location information of their towers. Too bad I can't demand that they shut down their service. Anyway, maybe they'll move the Azteca mux to a higher frequency transponder.
 
I put the other LNBF on my west dish and it performs a lot worse than the dish on the east side of the property. I guess I'll spend the bucks for a feedhorn, lnb, and waveguide filter. That's going to set me back a "few" bucks. I can't see any cell towers through the trees or houses when I'm 14 feet in the air (on a ladder) so I guess an RF fence isn't going to be adequate. But I'll have to think about what my options are before making any rash decisions. I put the other LNBF on my west dish and it performs a lot worse than the dish on the east side of the property. Too hot to mess with it anymore today. :(In the past a servo was used to change the feed polarity, how is it done today with DVB receiver (osmio4k). Looking at $487.
OK, I see how the polarization switching is done. Looks like it's going to cost more like $627 per antenna.
 
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I put the other LNBF on my west dish and it performs a lot worse than the dish on the east side of the property. I guess I'll spend the bucks for a feedhorn, lnb, and waveguide filter. That's going to set me back a "few" bucks. I can't see any cell towers through the trees or houses when I'm 14 feet in the air (on a ladder) so I guess an RF fence isn't going to be adequate. But I'll have to think about what my options are before making any rash decisions. I put the other LNBF on my west dish and it performs a lot worse than the dish on the east side of the property. Too hot to mess with it anymore today. :(In the past a servo was used to change the feed polarity, how is it done today with DVB receiver (osmio4k). Looking at $487.
OK, I see how the polarization switching is done. Looks like it's going to cost more like $627 per antenna.
Take a receiver and one of your LNBF's, (maybe an unfiltered one would be best for this?) and make a "sniffing" setup. Put the LNBF on a stick, connect it to a receiver, and point it around to try to determine just where the interfering signal is coming from exactly. Might take some time to do it, but might give you enough of an idea, and that's better than just guessing.
 
A satellite STB and an LNBF on a stick will not detect or identify the source of 5G terrestrial interference. 5G signals are not DVB format.

Instead, use a wideband LNBF and the XR-3 meter's spectrum analyzer. Look for random amplitude spikes in the spectrum display popping in/out below 3800 MHz, between IF 1350 MHz and 1450 MHz.

Math: 5150 LO minus 3800 = IF 1350 MHz and 5150 minus 3700 = IF 1450 MHz.
 
Many used Red filters are coming on the market, mostly for the export market.

Most US and Canadian targeted services have been relocated to transponders above 4000 MHz. The majority of commercial downlinks have now been swapped over from the Red filters (3800-4200 MHz bandpass ) to the Blue filters (4000-4200 MHz bandpass).

Your choice of filters depends on the frequency that you wish to receive and the frequency of the interference. Otherwise, it will be another game of "pin the tail on the donkey".

I think that TheEel will, either currently or in the very near future, may need to try and physically shield the dish in order to receive <4000 MHz transponders. With the expansion of the N77 band transition to 5G, one can't install a filter to remove the same frequencies that you wish to receive.
 
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A satellite STB and an LNBF on a stick will not detect or identify the source of 5G terrestrial interference. 5G signals are not DVB format.

Instead, use a wideband LNBF and the XR-3 meter's spectrum analyzer. Look for random amplitude spikes in the spectrum display popping in/out below 3800 MHz, between IF 1350 MHz and 1450 MHz.

Math: 5150 LO minus 3800 = IF 1350 MHz and 5150 minus 3700 = IF 1450 MHz.
I found signal levels as high as 0 dB between 1350 and 1450 with a 3700-4200 LNBF mounted at the antenna feedpoint with antenna on the west side of the house pointed at 91W and 113W. I had similar results panning east to west with the feedhorn while on top of a 7 foot ladder.
 
Please let us know how they work for you.
Yes, will do. Also, i originally heard that we could obtain these filters at no cost. Which would have been great since a new one is crazy expensive for what it is. But i guess that only applies to dishes registered to the FCC. :biggrin
 
I found signal levels as high as 0 dB between 1350 and 1450 with a 3700-4200 LNBF mounted at the antenna feedpoint with antenna on the west side of the house pointed at 91W and 113W. I had similar results panning east to west with the feedhorn while on top of a 7 foot ladder.
Definitely strong terrestrial signals that would wipe out signals near the edges of the bandpass filter! 3830 MHz typically has a minimum -45dB attenuation on <3800 MHz signals. Waveguide mechanical filters should be cable of -65dB attenuation, but still would not be enough attenuation to decode.

You might also check the 1170-1350 IF with the 3700-4200 LNBF. If seeing the same terrestrial signals in this portion of the band, they are within the bandpass and a physical barrier between the downlink and the source(s) might be the best solution. This portion of the N77 band might have testing, but not cleared for licensed terrestrial use until December, 2023.

Starting to feel like the old C-band TelCom microwave link interference whack-a-mole days from the 1980's!
 
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Definitely strong terrestrial signals that would wipe out signals near the edges of the bandpass filter! 3830 MHz typically has a minimum -45dB attenuation on <3800 MHz signals. Waveguide mechanical filters should be cable of -65dB attenuation, but still would not be enough attenuation to decode.

You might also check the 1170-1350 IF with the 3700-4200 LNBF. If seeing the same terrestrial signals in this portion of the band, they are within the bandpass and a physical barrier between the downlink and the source(s) might be the best solution. This portion of the N77 band might have testing, but not cleared for licensed terrestrial use until December, 2023.

Starting to feel like the old C-band TelCom microwave link interference whack-a-mole days from the 1980's!
I never experienced interference from terrestrial microwave back in the 90's until now. Anyway, I'd rather come up with a solution other than physical barriers. It might be cheaper to do a barrier but it might end up looking ugly. I prefer an electronic solution but it looks like it'll be expensive. I won't do cable or streaming. There's a way to stream Azteca but I would have to get a VPN into Mexico - too complicated for the wife.
 
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