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37 votes

Can my neighbor's ham radio antenna be interfering with my internet signal or is my internet provider just throwing blame elsewhere?

Could be, but likely not. In particular, almost no amateur radio station would be operating continuously, so if you have a problem that is not intermittent, that's unlikely to be the source of it. (...
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15 votes

Can my neighbor's ham radio antenna be interfering with my internet signal or is my internet provider just throwing blame elsewhere?

A "ham radio" is typically a transmit/receive system that uses certain frequencies set aside for radio amateurs to communicate with other enthusiasts. If there is a big antenna on your neighbor's roof,...
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12 votes
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What has happened to HF?

HF propagation is not only limited by manmade interference but also by natural phenomena like sunstorms. Anyway, I'd account that to social and technological reasons: HF activity suffers very much ...
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11 votes
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Attic Dipole - Impact of Ethernet over CAT5/6

Having Ethernet and your antenna co-located is not an ideal situation. But then most amateur antenna situations involve compromises. The general idea of the following recommendations is to take as ...
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  • 18.2k
10 votes

Can my neighbor's ham radio antenna be interfering with my internet signal or is my internet provider just throwing blame elsewhere?

A HF transmitter can interfere with a DSL service if the conditions are right simply by inducing more RF on the drop wire then the DSL modem (Which always cheap out on front end electronics) can cope ...
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  • 241
9 votes

Can my laptop pick up CB radio frequencies?

Yes, very strong radio signals can be picked up by just about any device with a speaker and a transistor in it. The transistor acts as a rectifier, forming a crude envelope detector. Amplitude ...
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8 votes

Can jamming a channel with white noise be detected?

The station would not really transmit static but rather white (or perhaps pink) noise. This would sound like static but as the observer tunes across the transmitter's frequency, the static would ...
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  • 18.2k
8 votes

How can I get rid of RFI coming from my house solar panel inverter?

The inverter in your solar panel system utilizes a high frequency switcher to regulate the voltage and convert it to AC for feeding back into the mains. Some solar panels also use an "optimizer&...
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  • 18.2k
8 votes
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How does FM station have fixed frequency when FM modulation changes the frequency?

"Tuning" an FM receiver sets the center frequency of the receiver, but its internal circuitry is designed to pass enough of the Bessel sidebands produced by frequency modulation of that waveform to be ...
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  • 2,882
7 votes

Can my neighbor's ham radio antenna be interfering with my internet signal or is my internet provider just throwing blame elsewhere?

Actually, depending on the power of the station, it could very well cause problems with any electronic equipment. I ran into a situation once where a band I supplied the sound system for had constant ...
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  • 71
7 votes

Can my neighbor's ham radio antenna be interfering with my internet signal or is my internet provider just throwing blame elsewhere?

I'm a tier 3 network support tech at a major Canadian ISP. Ham radio interference is a disturber our systems actually specifically check for, in relation to ADSL2+ and VDSL signals, and I've seen ...
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7 votes

What has happened to HF?

Before looking for reasons why HF activity "appears to be declining", we should look for evidence that HF activity is declining — so let's look at some available sources of data. While contests may ...
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  • 9,275
7 votes
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How to find something disrupting car key fobs across a parking lot?

There was a similar problem in the US a few years ago and it turned out to be a new shop sign that had a defective ballast that emitted a wide RF spectrum. Most key fob systems operate at ...
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  • 18.2k
7 votes
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Where does this common spurious transmission come from? Is there a quality difference?

This is very likely to be be due to overload of the receiver. A quick, rough way to tell the difference: Tune your SDR receiver so the waterfall center frequency is not the same as the transmitter's ...
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  • 23.1k
6 votes

Advantages of using Digital Code Squelch

DCS (aka DSQ/DPL) provides a slightly larger range of codes to pick from compared to CTCSS. This means less chance that a nearby station will accidentally overlap with yours. Specifically, DCS gives ...
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6 votes

How to detect common-mode currents or “RF in the shack”?

Another way to detect current on the outside of coax is to run your hand up and down the coax wile an analyzer is connected , if you see a fluctuation on the meter then current is following on the ...
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6 votes

Can you jam jam?

A receiver's objective is to take some message which has had noise added to it, and recover from that the original message. Receivers need to do this even in the absence of jammers since natural ...
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6 votes

What is the purpose of limiting radio output power?

I'd speculate a large part of the justification is that amateur stations, unlike commercial broadcast stations, are not periodically certified to meet spurious emission regulations. Or any regulations ...
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6 votes
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HF Noise Level S5 to S9+18

Some troubleshooting ideas: Check your radio's power supply for noise by substituting a battery and disconnecting the PS from the wall. Run your receiver on a battery and turn off your main breaker. ...
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6 votes
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How do active loop vs. passive loop differ in terms of noise rejection?

Loops (active or passive) don't have the RFI rejection capabilities they are often claimed to have. RFI is electromagnetic radiation just like the signal, and it's not possible to design an antenna ...
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6 votes
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Do chokes at the antenna feedpoint stop the coax from receiving signals as well, or just transmitting?

By the principle of reciprocity, if it works for transmit, it works for receive also. Possibly if your receiver and transmitter are separate devices you may end up with a situation where no common-...
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6 votes
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Transmitted audio coming out through my speaker

The manual, on page 56 says: TX monitor allows you to monitor the on-going transmission sound. This is convenient when you want to check the modulation sound quality of the transmission. In FSK mode, ...
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  • 8,235
5 votes
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Noise & shielding, SDR Dongle

While the other answer is quite detailed, this one is much shorter and specific: I purchased and installed an aluminum RF shield for the dongle. The noise floor is significantly lower as a result! ...
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5 votes

Noise & shielding, SDR Dongle

“Sensitivity” isn't all that well-defined. Insofar as it is, you might as well just think in terms of noise, because there is always a noise floor and it's always what determines the weakest signal ...
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  • 23.1k
5 votes

OK for S/RF light to be illuminated at engine idle?

If your car uses petrol (gasoline) rather than diesel, then the ignition system can potentially generate a lot of noise because of the high-voltage system used to generate the sparks that ignite the ...
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  • 4,409
5 votes
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Understanding coax radiation and "current on the shield"

Perhaps some of my confusion comes from an audio background, where one has "balanced" and "unbalanced" cabling in a way that is easier for me to understand: an unbalanced cable is simply a signal and ...
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5 votes

Can my neighbor's ham radio antenna be interfering with my internet signal or is my internet provider just throwing blame elsewhere?

Short answer: Based on your description of the scenario, it's possible, but seemingly unlikely, that interference received from the ham radio is causing your problems. Longer answer: Kevin's answer is ...
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  • 151
5 votes

Cordless phone consistently experiencing RFI

First, let me say that most hams would be delighted to have such a polite neighbor! I would encourage you to contact your ham neighbor. Most hams are more than pleased to help neighbors with ...
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  • 8,922
5 votes

Cordless phone consistently experiencing RFI

If the interference is coming into your telephone via the RJ-11 cable, then the type of ferrite material you use to suppress the interference will matter. Engineers refer to the type of ferrite as the ...
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  • 18.2k
5 votes

Weird Harmonic Issue on Raspberry PI FM Transmitter

There are many articles which describe how to use a R-Pi to emit (=transmit) a signal. However what most, if not all, articles fail to describe is that this signal is a very rough signal, usually not ...
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