G8JNJ
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Yes, it's a pity that the BlackCat logger looses information when the KiWi reboots. I've also found this to be a disadvantage if you wish to keep a long term record. Your Python code seems to be more useful. I wonder if a daily (24 hour) max / min v…
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I take the point you are making, and your understanding of the responsibilities and trades to be made, but unfortunately, I suspect you are in a minority among typical web sdr users. There are some people who simply sit on a channel, or channels, a…
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Wow, that's an interesting idea, thanks John. Maybe this improved granularity could eventually somehow provide a more accurate measure of the overall quality of reception for a given KiWi at a given time. I also wonder if some known "quiet&quo…
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I think ideally I'd test the rooftop antenna position, before spending money and effort to make it more permanent. Can you somehow hoist the loop up and try it ? I suspect that placing the loop in such close proximity to everything in your house, wi…
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If your KiWi is on your local network, you can add /snr?meas to the url to force an SNR measurement. This was added for pretty much the scenario you desire. This is also what the cron job that was suggested earlier, automatically triggers at the re…
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Looks like a nearby lightning strike, but a good indication that the surge protection devices have actually done their job, and yes the KiWi should have an effective protective ground connected at some point. I've been on hilltop radio sites when th…
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My response was intended to be complementary to your original posting, but from a KiWi operator's perspective. The majority of my users are responsible, some do occasionally take the time to provide feedback and encouragement, most just use my KiWi'…
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It should be OK, but these lightweight rotators have a limited lifespan, as the thrust bearing ball race is usually pretty poor. Do you need to mount your loop on the roof ? It may be better at a a lower height, but in an electrically quieter locati…
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I think your question is more about the ethics of fair use of a free* but limited resource. Unlike Twente which can support hundreds of simultaneous users, a KiWi will typically only support four. This usually not a problem when used for short perio…
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Interesting. The Bonito MegaLoop FX seems to be producing the best signals, but a lot of the noise is still present with the power removed. When power to the antennas is removed, I wouldn't expect to see such high levels of noise and interference. …
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With any adjustable power supply, once you have determined the correct settings for your application, I'd suggest replacing the variable resistors with fixed values. It's so easy to accidentally knock the controls and fry any kit that is connected d…
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That's a bit more helpful. I think you have a few problems, and I'm not sure if there is an easy solution. The noise floor is relatively bad, but I think it would look a lot worse if the MFJ loop had a flat frequency response. The relatively high va…
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I honestly don't know what's going on, but something doesn't seem to be correct. The signal levels seem incredibly low, although there is some variation when you rotate the loop. The loop amplifier is very simple, and uses two GALI-74 MMIC devices, …
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OK understood. If the antenna is on a balcony in an apartment block, it's very difficult to get away from sources of interference. However, all the signal levels seem to be very low. Do the wanted signals and interference levels change when you rota…
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The series of waterfalls is not as useful as a series of spectrum plots, as suggested by Glenn. However, apart from the interference I can see no obvious short wave signals, so how is your receiver and antenna configured ? Is this just the KiWi with…
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Glenn with respect, I also said " or by reducing the amount of noise present by some other method." This was intended to encompass other factors, such as those you have mentioned. The key thing was that the local noise, introduced by what…
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Hi Glenn, I don't disagree, which is why I stated "Any further improvement can only be brought about by using a better antenna, or by reducing the amount of noise present by some other method." If for example you have a problem with noise …
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Before anyone gets their credit card (or other method of payment) out. Make sure you actually need a pre-amp. In most cases, you will not, they are useful in specific situations, but unfortunately for the majority of KiWi owners, local noise and int…
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It's an amateur Slow Scan TV SSTV calling frequency. Listen between approximately 7033 and 7085kHz, and you will hear lots of other strange sounding digital modes. Regards, Martin
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That amplifier uses the same Qorvo TQP3M903 device, so I'd assume it's the same circuit too. As before, the IMD performance isn't really sufficient for use ahead of a KiWi. SV1AFN produces some good amplifiers that work well. https://www.sv1afn.com/…
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Oh and also, the SNR measurement method is seriously flawed, and can easily be fooled. The human eye and brain can very quickly determine if the spectrum and waterfall looks "clean", but it's a lot harder to find an automated method that w…
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If you are using an unbalanced antenna, it needs something to provide the "missing" half, that would otherwise be present in a balanced antenna. All simple antennas are basically dipoles. It's just that sometimes you can't figure out where…
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Looking at the AliExpress pictures, it would seem to use a Qorvo TQP3M903 700 - 6000 MHz Ultra Low Noise, High Linearity Low Noise Amplifier https://www.qorvo.com/products/p/TQP3M9037 Although many devices of this type can operate outside their spec…
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https://forum.kiwisdr.com/index.php?p=/discussion/3588/consider-increasing-spectrum-display-vs-wf-screen-real-estate Hi Glenn, Having also had a background in RF engineering, and being used to spectrum analysers, I'd also support the ability to modi…
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I'd suggest checking your power supply, as an initial part of any investigation.. I've had similar problems, and it's nearly always turned out to be power supply related. On particular problem is poor quality electrolytic capacitors that "dry&q…
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https://en.wikipedia.org/wiki/Alpha_(navigation) http://www.vlf.it/alphatrond/alpha.htm
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Sorry, this makes no sense to me when run through Google translate, and I suspect it is spam. Discussions on this forum tend to be in English, and posting in English will give you a better chance of receiving any replies. Regards, Martin
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Sorry, this makes no sense to me when run through Google translate, and I suspect it is spam. Discussions on this forum tend to be in English, and posting in English will give you a better chance of receiving any replies. Regards, Martin
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Sorry, this makes no sense to me when run through Google translate, and I suspect it is spam. Discussions on this forum tend to be in English, and posting in English will give you a better chance of receiving any replies. Regards, Martin
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The tuning steps default to +/- 5kHz above 7200kHz in some regions, where there is no amateur allocation above that frequency and it remains a Broadcast only allocation. Regards, Martin