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6

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, you can monitor the FSK signal that the transceiver is transmitting. 1 Press and hold [PWR (TX MONI)]. • The current TX monitor setting appears on the sub-...


5

the short answer to #1 is that it is possible but not at all likely for the same reasons Kevin outlines in his answer to the question you linked to, especially the fact that almost no ham radio operators transmit continuously... only when actually having a conversation, and only when it's our turn to speak in the conversation. Answering #2, the directivity ...


4

In the April 2016 issue of the ARRL's QST magazine article, "Can Home Solar Power and Ham Radio Coexist?," K1KP tracks down and attenuates RFI generated by his multi-kW rooftop solar installation. Using sensing loops and antennas connected to an all-band HF transceiver, Tony detected RFI from every part of the installation, though radiation from ...


4

The RFI is generated by —and is radiated from— the screen itself. You would have to put the plasma TV inside a Faraday cage to eliminate your RFI. This is why plasma TVs are no longer being made. (Having said that, there was at least one brand of plasma TV (Panasonic?) that was not a prolific RFI generator.) A plasma set, unlike a LCD, requires relatively ...


4

161.775 isn't a frequency reserved for weather broadcasts in the US, no. CMB is a Canadian service; the same allocation doesn't exist in the US. NOAA All Hazards Weather Radio stations are on channels from 162.400 to 162.550 MHz. According to RadioReference, WGN-TV has an IFB channel at 161.74875 and a remote audio channel at 161.77250. These are channels ...


4

A ferrite core used for radio is specially constructed to conduct magnetic fields while not conducting electrical current, especially eddy currents. A slinky is (typically) an uninsulated conductive coil of variable spacing, and thus variable inductance. It is nothing like a ferrite core. Typically they are made of steel which his high resistance (for metal)...


4

Look around your neighbourhood or Google satellite imagery for new solar panel installations. We recently discovered a solar panel installation with noisy regulators creating noise at a neighbours house. Also as you mentioned that LED lights are also creating noise. Look for new street lamp installation nearby that is using the new LED replacement lamps.


4

Ham radio and marine radio are separate unrelated services. Marine radio is used on boats, and this looks like a house, not a boat. Both ham radio and marine radio transmit intermittently. If you are seeing something continuous and 24/7, then it can't be from either a ham service or a marine service. Variations in the intensity don't make a difference ...


3

No. It's not possible for RF to make things reverberate at a high frequency; at least not without making your brain boil. Your photo is not high enough resolution to see anything. Literally. Also...it's not Marine HAM; the two are not mutual and HAM is not an acronym and should not be capitalized. You might want to purchase an ultrasonic detector and find ...


3

Solved! It was the wireless charging pad integrated into the top surface of the device, which thankfully they provided a means to disable.


3

The likelihood of an antenna interfering with another antenna diminishes as their respective frequencies get further apart. Typically, if they are on different non-harmonic bands, it won't be an issue, and if they are harmonic, the higher frequency antenna might cause interference on the lower frequency antenna, not the reverse. Dishes are probably above ...


3

Of course there can be interference but I would guesstimate the probability at about 30%, so that 70% chance that there will be no interference - basically have to try to find out. If there is interference you can move the antenna a little bit and that might even fix it or install a filter that might fix it, or use less power on certain frequencies. I would ...


3

The panels themselves are essentially photodiodes, producing DC when exposed to light, and so generating no RFI. A very simple system consisting just of panels and a battery could generate no RFI at all. However such a system system is not very efficient. There is an optimal impedance which the panels should see which optimizes the product of voltage and ...


2

The answer... Various sources can cause this. One common source of interference are battery chargers; either at your house or a neighbor's.


2

You might consider an RF choke at the interface between your radio and feed line. The choke at the feed point will help prevent common mode current reflecting from the antenna... but the outside of the shield can still be a source of noise on receive if it's not also choked at the receiver. In fact, you might test what happens when you put a dummy load at ...


2

If the RF noise is that strong, then you should be able to pick it up with a much smaller movable antenna. Even scrap wire or conductive tape on a large cardboard box. That may allow you to build small directional antennas (tiny loop and stub dipole) to determine if the noise is stronger from some specific directions, or a polarized antenna to determine ...


2

Start by trying to determine if the noise is "conducted" or "radiated" into your receiver. Basically, "conducted" noise gets into your receiver from the power supply or a ground wire or some other cable. "Radiated" noise gets in via the antenna. Start by powering your radio with a battery instead of the mains-powered ...


2

I'd suggest trying a different time of day, a different radio, a different antenna, and a different location; not necessarily all at the same time though. There's probably nothing wrong with your antenna, but you might get different results at different heights, or if you raise the height of the ends to the same height as the middle. Have you tested the ...


2

Identifying RFI just by the waterfall is not usually possible. A more productive approach is to find the source physically, then the source will be obvious. If it's in your house, you can narrow down the source by turning off breakers and unplugging individual devices until the culprit is identified. If turning off your main breaker doesn't eliminate the ...


2

You are saying the noise is constant. Ham radio does not broadcast constantly with the possible exception of a beacon which by definition is low power. You might want to politely ask your neighbor if they can assist you in tracking down the cause of the interference. Most Ham operators have experience in tracking down and remedying sources of electronic ...


2

Combination of a neighborhood power outage (which unrelated to this reduced the noise floor from S-5 to S-1...sigh) and a portable AM radio I scrounged up solved it. It turns out it was a UniFi USW-8-60W network switch (it was on a UPS I had forgotten about which is why I missed it when I did my "main breaker off" test). Oddly, I have three of the ...


2

It seems to me that you have a bad radio, that is to say a radio with one or more faults in it. You shouldn't be getting the sensation of a shock or heat, and those are possible indications of a short. Direct shorts are sometimes easy to troubleshoot. The intermittent static issue could be an aspect of the same problem, or it could be an independent ...


2

I think you have a loose wire in there somewhere. It's probably the ground or center lead between antenna and amplifier. The bursts of static might be from the wire making contact or not, or contact with something else. Are the static circles repeatable or maybe it was a coincidence, maybe the way you are holding the radio, you can try holding it upside-down....


1

Since the transmitted signal is affected this must be a caused by interference on the supply voltage. The generator is most probable source for this interference. Simple filter in power supply line: inductor plus capacitor will probably help. Edit/addition: The pulses or RF noise are present on the supply voltage. Two options: the RF noise is present at the ...


1

You've received several good answers here. To Brian's answer suggesting that you should try powering it from a battery, I would add start with your own house before running around the neighborhood with a radio by turning off your main circuit breaker. This will determine whether or not the RFI is coming from something in your house, which is quite likely. ...


1

I purchased a West Mountain CLR/DSP 58407-949 noise reduction unit. Seems to help but still requires a strong signal to break through the QRN. I run an FT-450D also.


1

A slinky as in the one you watch go down the stairs? I'd assume not. Any winding on a slinky would probably act as inductor/transformer with an air-core. Ferrites have special magnetic properties. There is a reason they are expensive.


1

Check this video of one hams quest to stop some RFI https://youtu.be/Pwbk8yP6SIk


1

Ferrites can certainly be effective in blocking RF. But so can capacitors which short RF energy to ground. Place them on incoming lines and anywhere rectification of the RF signal could be occurring. Both methods can be used in stubborn cases.


1

Talk to the Ham Op next door. We are more than happy to help cure a problem, and as a Ham myself, I have these Filters all over the place,"Hams have RFI also". 73 de kg0tr


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