5G interference solutions

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But the one I plan on building will consist of a laptop computer, an SDR (software defined radio), an unfiltered C-Band LNBF, a 13 volt power source with a bias tee to power the LNBF, a 12 inch wide parabolic dish and my SDR Program named DR Processor running in wide band mode. Or I may decide to use another SDR program: Spectrum Analyser

I have strong 5G interference in my area. I intend to find where it's coming from.
I finally found time to build a 5G hunting device (photo below). I'm using a 12.6V Lithium Ion battery from a cordless drill to power the LNBF. I installed a DC blocking capacitor to protect the SDR from 12.6 volts.

For this project I used the CTC (Clear Tape Construction) method. :) It's not elegant, but it will suit my purposes since I will not be using it forever.

For improvements I should add an on/off switch for the 12.6 volt battery which powers the LNBF. For now I just unscrew it from the LNBF when not in use. I also need to find a better cable for my Airspy SDR (the one that has a choke).

Am now going to setup my Windows laptop with the Airspy software and an SDR Program that can do a 100 MHz at a time.

Hopefully later today I will have it all working and will find the closest source of 5G band N77 in my area. I just hope that no one calls the police on me thinking that I am spying on them. :)

5G_Finder.jpg
 
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I tested my new 5G finder using "Spy Sweeper", which can cover 500 MHz at a time. But most of the time I had it set for 100 MHz bandwidth for faster update speeds.

First I tested the directionality with a 500 MHz bandwidth. When pointed at the Clark Belt I could see the signal intensity increase. When pointed down the signal dropped substantially. So I conclude that I have a directional antenna.

Next I had my wife drive me around town with the bandwidth set at 100 MHz in band N77. I noticed 5G spikes mostly in the direction of travel, or behind us. This makes me think that its coming from 5G cell phones in cars.

When we drove through residential neighborhoods, the signal spiked at times as we passed certain houses.

So it seems that I have found end user devices with 5G (lots of them), but not the tower that serves them (yet).

Looking forward to doing more hunting and finding the 5G tower, or street light with a mini 5G node on top.
 
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Cool project! :)
Thanks. I've been thinking about it for several weeks and I finally got around to building it yesterday and finished it today.

For my next test, I am going to connect the AirSpy SDR to my 10' Unimesh. Will have SpySweeper set to monitor 5G in near real time and will do a screen recording.

Will try it with the C138 and then an unfiltered LNBF......
 
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The C band interference situation has come full circle on us. When home satellite was born we had to work around AT&T Long Lines microwave radio shots. It was so prevalent in my area I carried an 8 foot rear feed Janeil dish to each potential site on a trailer to see if terrestrial interference was going to be a problem. We even had interference at our showroom in downtown Salem, Or. When you consider that the microwave radios only used about 1 watt of RF, the damage they did was real.
 
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...

When we drove through residential neighborhoods, the signal spiked at times as we passed certain houses.

So it seems that I have found end user devices with 5G (lots of them), but not the tower that serves them (yet).

Looking forward to doing more hunting and finding the 5G tower, or street light with a mini 5G node on top.
I drove around my neighborhood today with the signal finder and it seems that it gets equal intensity 5G in almost every direction. 5G emissions seem to be coming from everywhere.

The only thing I have noticed when driving around is that if I am at the bottom of a hill the 5G is weaker than at the top of the hill.

I'm going to replace my iPhone 8 with an Android 5G phone and will do more testing....
 
Probably a stupid thought. Would that mean if you believe 5G interference is manifesting your signal. If you put your cell phone at the focal point of your dish at the lnbf throat the bars would peg?
 
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I get 4 bars on my phone for 5G. I suppose that's why I've had reception problems on both C-band antennas lately. So, I ordered a Titanium C138-5G to see if that'll help.
 
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Probably a stupid thought. Would that mean if you believe 5G interference is manifesting your signal. If you put your cell phone at the focal point of your dish at the lnbf throat the bars would peg?
I haven't tried it but I would guess no. Because the 5G interference at your dish could be coming from multiple sources.
I get 4 bars on my phone for 5G. I suppose that's why I've had reception problems on both C-band antennas lately. So, I ordered a Titanium C138-5G to see if that'll help.
I'm sure it will help a lot.

... I got a 5G Android phone Sunday and tried it out. But it installed Tik Tok and some games on it's own without my permission so I wiped the phone back to factory default and returned it back to Amazon.

Going to have to get another 5G phone if I want to do testing.
 
I haven't tried it but I would guess no. Because the 5G interference at your dish could be coming from multiple sources.

I'm sure it will help a lot.

... I got a 5G Android phone Sunday and tried it out. But it installed Tik Tok and some games on it's own without my permission so I wiped the phone back to factory default and returned it back to Amazon.

Going to have to get another 5G phone if I want to do testing.
Yeah, I hate it when they install apps that I didn't request. Some Android phones can be rooted that will allow you to do administrative stuff and install custom firmware. I haven't come across a phone that I could root.
 
I haven't tried it but I would guess no. Because the 5G interference at your dish could be coming from multiple sources.

I'm sure it will help a lot.

... I got a 5G Android phone Sunday and tried it out. But it installed Tik Tok and some games on it's own without my permission so I wiped the phone back to factory default and returned it back to Amazon.

Going to have to get another 5G phone if I want to do testing.
From tests EB and others have done over on legit. 5G interference on a dish doesn't come from side lobes but rather from sources in line with the dish. Yes/No? Looking back in this conversation I only see mention of 101W & 105W.
Those two are relatively low on the horizon even at my latitude around 42N.
But if in fact the interference was coming off of the side you should be able to snag it on a tp and steer your dish around and see if your signal decreases or is still there. Make any sense? I guess living in the boonies does have its plusses. Like getting my dinner from the spring out the back door in a few minutes.
 
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I "received" my 5G Titanium LNBF from Amazon today. Only problem is that there's no LNBF in the box, only the scaler and some hardware. It was poorly packaged also. The box had some damage also.
 
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I "received" my 5G Titanium LNBF from Amazon today. Only problem is that there's no LNBF in the box, only the scaler and some hardware. It was poorly packaged also. The box had some damage also.

Sounds to me like somebody bought it, took out and kept the lnbf, then returned the rest and you were the 'lucky' one who bought it next. :(
 
Sounds to me like somebody bought it, took out and kept the lnbf, then returned the rest and you were the 'lucky' one who bought it next. :(
Could be. I don't need the scaler either. The scaler is just a waste of money unless it's a new install.
 
I am experiencing a random problem with both C Band and KU becoming pixelated at times. I don't have any 5G close to me that I can find. Closest possibility is to the left of my part of the arc. I would think it might be an adjacent carrier firing up with a strong uplink signal. But that doesn't explain the KU probem . The problems only affect the MeTv mux on 101W and the COZI Tv carrier on 103 KU. When it does happen it does so often and always during the Emergency! time slot on KU and at roughly the same time slot on C Band. I know the power company has a bad arrestor on the pot that serves my home but I can't see it causing this sort of problem. I think my HP Service Monitor's spectrum analyzer will handle the C Band LO frequency so it looks like it's time for a hunt! I'm guessing 5G would look much the same but I don't have a 5G phone so I can't swear to anything except there is absolutely NO cell service at home regardless :) Some good info in this thread!
Regards,
Wayne