G8JNJ
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Hi, Can you tell us where you are located, and what type of space and environment you have available for antennas, as this will define what you can receive. My Wessex SDR's, located on a hilltop in the SW of the UK, have exceptional reception, and I…
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Can you manually set up port forwarding on your router, to allow external connections ? Regards, Martin
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No, a lot of the interference you have is being radiated by the noise source itself, and received via your antenna. I commented on the various ones I could identify in a previous thread. https://forum.kiwisdr.com/index.php?p=/discussion/3666 Regards…
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Linear supplies tend to be quieter than switched mode supplies. But they can generate some noise. The biggest problem is often that they can introduce an additional noise route via the mains earth, which may not happen with small switched mode units…
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It depends... If the Apple charger is actually contributing noise in the first place, but it may not be. There are so many potential noise sources, in, and around the home, that it may not be possible to observe any difference if you swap out the Ap…
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The noise centred around 500kHz, with narrowly spaced carriers, is from a switched mode power supply You have occasional intermodulation products around 99 & 332kHz when the ADC is being overloaded and the Red OV indicator is flashing. Currently…
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OK found it http://lowestoft.proxy.kiwisdr.com:8073/ The rapidly pulsing interference is from one or more Ethernet data over mains powerline adaptors. The noise band from approx 8.5 to 12MHz is VDSL Upstream frequency band U2 I'm not sure what the n…
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Can you provide a link to your KiWi ?
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I use old style 12V 3A or 5A Linear CB power supplies, often available cheap at car boot sales or radio rallies etc.
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I seem to vaguely remember that VARA HF modem has a test / setup mode that generates sweeps. However, I can't find an example, so I may be wrong. Regards, Martin
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If it is really 6765 USB, it's most likely Bangkok meteo FAX. If it is 7150 LSB it's most likely one of the many, and increasingly difficult to identify, Amateur data modes. Regards, Martin
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Unlikely. With reception, it is not about obtaining the strongest signals, but maximising the Signal To Noise Ratio. A lower height in a different position may work better. Once you get above a certain height above the ground reference, you may star…
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You don't mention the size of the loop you intend to use, but in most cases it will require a balanced amplifier (or an unbalanced amplifier and a balun), with a low noise figure and about 20dB gain, to provide a sufficient degree of sensitivity for…
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I agree that the SNR measurement function is flawed, and appreciate that you, John, may have spent more time on it than you would like. However, even in its current form it is far better than having nothing at all. This is especially true when using…
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Ah OK, however it would be interesting to see if John's filter, also responds to broadband noise that looks like VDSL. I wonder if there are several consecutive FFT bins, that contain the same level, could this be interpreted as wideband noise rathe…
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The most obvious one is http://zl4md.proxy.kiwisdr.com:8073/ It is consistently near the top of the SNR leaderboard, but has a massive block of noise from 8.5 to 12MHz In the UK, but already poor SNR http://21246.proxy.kiwisdr.com:8073/ http://remo…
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It's difficult to provide any advice or assistance, based on your description alone. Maybe provide a link to your KiWi, so that we can listen for ourselves ? Regards, Martin
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Oh dear, that's odd, as your Overload indicator is flashing too, despite there being no signals evident. http://w3ilt.proxy.kiwisdr.com:8073/ Good luck, Martin
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Hi Glenn, I thought he was initially making a deliberately bad layout, to emphasise the design aspects. But maybe I misunderstood the part you were referring to. Regards, Martin
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Hi John, Thanks for responding to that problem. Regards, Martin
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If it is something like a PC, and it's not on your property, it could still be in an adjacent one. However, as modern electronics pop up just about everywhere, this is still just a guess. You may have to build a small tuned loop and go "hunting…
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I think the fact that they are closely spaced in frequency and synchronised with each other, suggests to me that they are a local interference source. I have seen many similar signals, and they often originate from PC's, or other devices using micro…
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Try https://amradioantennas.com/contact_us.htm
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Check the DC input ferrite CMC filter (T301) on the KiWi board, a small grey rectangular item, just behind the socket, that is the item that most often tends to get blown up. If it has blown open circuit, the easiest fix is to remove it from the boa…
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These are typical of RF welding / Drying / Curing processes. Very high power RF sources are also used during some types of semiconductor manufacturing processes. Another source, is from the cheap Chinese "Radio Frequency Facial Machine" or…
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As I commented in my original post regarding the power supply. "One particular problem is poor quality electrolytic capacitors that "dry" out over time, and the power supply smoothing and regulation suffer as a result" I would su…
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Well done on the TDoA, especially as it doesn't work too well on CW or FSK. I made several TDoA runs during grey line propagation, and initially thought it was from Germany. I should have known better. I used two separate browser instances with my K…
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It's a common US HFGCS frequency, and they are sending an encoded Emergency Action Message (EAM) Nothing to worry about (yet) these are very common transmissions. But I'm pleased your SNR is creeping up :-) Regards, Martin
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Good luck. I don't use mine that much, but if you are interested in radio, it's always handy to have an amateur licence. In the past, it used to be a valuable "pseudo" technical qualification when seeking employment, but those days are lo…