Horrible Wireless Internet Site Noise Everywhere

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Birken Vogt
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Horrible Wireless Internet Site Noise Everywhere

Post by Birken Vogt »

We recently inherited a system that has a multitude of voting receivers and nearly every site has some sort of WISP presence on it and they are utterly destroying us. We are on VHF-hi. Usually they get us by 20 dB. The receivers are MTR2000s. The sites are everything from regular repeater installations, to cell towers, to private whatever. Wireless is provided by various companies, all small and private and with no concern for anybody other than themselves. It is always CAT5 to the units and we know the CAT5 radiates a lot of garbage whether or not it is shielded but the microwave units themselves are pretty bad too.

One manufacturer I have seen a lot of is "Radio Waves" and that always makes me chuckle, not in a nice way.

Does anyone have any success stories on bringing the hammer down on these spectrum polluters? Are there properly engineered products they could be using? Do they have to use waveguide and microwave inside the building like the Good Old Days?

Thanks
Birken
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Bill_G
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Re: Horrible Wireless Internet Site Noise Everywhere

Post by Bill_G »

You can start by appealing to the site owner.
Jim202
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Re: Horrible Wireless Internet Site Noise Everywhere

Post by Jim202 »

Pull the power plug out of the wall outlet and attach a note that it is causing interference to other users at the site. Notify the site owner of the problem.

Jim
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Astro Spectra
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Re: Horrible Wireless Internet Site Noise Everywhere

Post by Astro Spectra »

Tell the site owner that the use of unscreened CAT5 cable and unshielded RJ45 connectors has killed the value of the site and you're considering moving out.

Let him know that the lack of investment of a hundred dollars in good cable and proper terminations is causing an RF nuisance at the site.
Birken Vogt
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Re: Horrible Wireless Internet Site Noise Everywhere

Post by Birken Vogt »

I'm not sure just switching to shielded cable is the solution. At our own site we made the wireless tenant do that and it did not help very much. It seems that the equipment itself radiates a lot of trash, also.

This is a small town. If we start making a big stink, the wireless people are going to come to us asking what should they do? Go out of business is not a very good answer. Is there alternative equipment available that does not throw all this trash? Do any of you guys have sites that are loaded with wireless and have clean VHF receivers anyway?
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Astro Spectra
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Re: Horrible Wireless Internet Site Noise Everywhere

Post by Astro Spectra »

Yes I do along with Cisco routers. But screened cable is not enough you must use properly shielded RJ45 connectors. They of course need to plug into shielded scockets. If the wireless network kit has plastic RJ45 sockets then that's a fail. As you say some gear is better than others, the worst simply does not meet Part 15 specs, despite the label. I've found the metal cased Ubiquiti 'Titanium' Bullets good.
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Bill_G
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Re: Horrible Wireless Internet Site Noise Everywhere

Post by Bill_G »

Birken Vogt wrote:I'm not sure just switching to shielded cable is the solution. At our own site we made the wireless tenant do that and it did not help very much. It seems that the equipment itself radiates a lot of trash, also.

This is a small town. If we start making a big stink, the wireless people are going to come to us asking what should they do? Go out of business is not a very good answer. Is there alternative equipment available that does not throw all this trash? Do any of you guys have sites that are loaded with wireless and have clean VHF receivers anyway?
Tell us about the site -

Are you the incumbent, or are they? If you are, then you can make them clean it up with a formal FCC complaint. If they are, then you need their cooperation, or you need to pick another site.

How much vertical separation is there between your receive antenna and the wireless access points?

Have you looked at it with a spectrum analyser on your antenna? Is it a generally raised noise floor across the VHF band, or do you see strong birdies that happen to land close to your freqs?
Birken Vogt
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Re: Horrible Wireless Internet Site Noise Everywhere

Post by Birken Vogt »

There are at least 6 sites that have this trouble, most very bad.

The equipment is very large microwave dishes or flat panels that are 2 or 3 feet in diameter or length, or larger, of many different types. It all looks like the kind of stuff that the manufacturer should know better. Is there a way I can host pictures here or do I have to do it elsewhere and provide a link?

I believe we are incumbent for the most part. I will need to research that. However we are also just a remote receiver on most of the sites and the wireless stuff is many times our size so the rent might be as well, so I want to tread softly with the landlords.
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Bill_G
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Re: Horrible Wireless Internet Site Noise Everywhere

Post by Bill_G »

Going back to the sites - Can you get any separation from their equipment? That is what it's going to take. You need a lot of space between you and them. There needs to be some site standards where dishes go at this elevation, xmit antennas at this elevation, and rcvr antennas at that elevation (hopefully the top). Grounding standards apply. Wiring standards apply. Tenant cooperation rules apply. Etc etc. But, you have to have your ducks in a row. If the sites are unmanaged, then you're in hades - enjoy the heat.
mike m
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Re: Horrible Wireless Internet Site Noise Everywhere

Post by mike m »

Just be happy you are on high band, we have site at 8000 feet in Central Arizona on vhf low band and a similar problem that comes and goes depending on the number of users on the equipment, but mostly the big 'V' digital noise never receeds.

So far we determined that the noise is caused by to many to list, poorly designed and unshielded digital products.

On VHF LOW BAND the noise is at a minimum an order of magnitude worse than at 147MHz; however I also measured 10db degradation at 224 MHZ which gives you an idea as to how much crud this crap puts out.

It is so bad that it makes a low band repeater, that at one time used to be capable of hearing a handheld at 15 miles, unusable now with a 110 watt mobile or base at the same distance.

The only good thing is that there isn't much snow and ice this year to deal with so the snow cat stays home.

And yes we are in the same building as our noisy neighbors.
VE3TUH
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What radios do you own?: more than I should...

Re: Horrible Wireless Internet Site Noise Everywhere

Post by VE3TUH »

I wonder if some form of preselection might help you, in the form of either a formal preselector, or just some tuned cavities on your RX.
VA3HF
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Re: Horrible Wireless Internet Site Noise Everywhere

Post by VA3HF »

Shielded CAT 5 cable with grounded RJ45 shield connectors into metal boxes if equipment is plastic. I've seen very noisy consumer grade Ethernet switches and routers used at some places that radiate noise everywhere. Unlikely the actual RF signal from the antennas are the cause - too far away in frequency. It is the Ethernet lines and computer electronic devices that are the problem.

Shielding and shielding and shielding.
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Cam
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Re: Horrible Wireless Internet Site Noise Everywhere

Post by Cam »

Interesting problem. I own an ISP that is in some ways a WISP (we do fiber and wireless, more PtP, less PtMP then a standard WISP) and we have almost no problems with our many site neighbors. At many of our high profile sites we have VHF airband, VHF hi, UHF both conv and trunking systems, 800mhz public safety systems and 900 mhz smrs as well a little bit of cell, though almost all of that has moved to lower, smaller sites. The problem I can remember besides us causing interference to ourselves was when Verizon was rolling out 700 Mhz LTE one model of backhaul radio we used caused them problems. We worked with them and the manufacturer who wrote a firmware update that change the CPU speed and fix the problem. At one site our own UHF repeater antenna is on the same mount as a 5g sector and a 3.65g backhaul dish with the repeater itself in our rack with a good number of switches, routers and power supplies, never a problem. Of course we don't use any unshielded cabling and use shielded RJ45s, our radios use shielded jacks and our power equipment has shielded jacks that tie into the case ground. Most of our lower end radios we also use an aftermarket shielding system build out of aluminum, more to help of with freq reuse then anything. Many of our PtP radios are feed by fiber and a DC cable.
Sounds like maybe you have some guys using old gear build from parts or just bad install practices.
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Bill_G
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Re: Horrible Wireless Internet Site Noise Everywhere

Post by Bill_G »

I had railroad crew radio go deaf because of wideband doo-doo created by a wifi access point installed by a wireless camera contractor on the antenna mast. They added security cameras to the yard that aggregated to this AP. It was a POE device with the outdoor unit mounted a foot down from the antenna that raised the VHF noise floor 40db or so. Pretty horrible. I can't say positively whether it was their choice of cable, or the ODU, but I can say that pulling the plug on the injector fixed the radio. The security contractor didn't have a solution. Eventually I had to put a cable stretcher on the antenna, and moved it to the other end of the building away from the ODU.
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