G8JNJ
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For transmit purposes, it's all about antenna efficiency, and radiating as much of the applied RF power in the direction you want it to go. For reception purposes, it's all about the Signal to Noise Ratio, and a good transmit antenna may not always …
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As I said previously, the majority of Bias Tees have very poor filtering between the DC line and the RF path. Nearly all the circuits you find on the internet tend to be outlining theoretical designs, that concentrate on providing the least attenua…
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Check the antenna Bias Tee first. Many don't have enough filtering built into them. Regards, Martin
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Before swapping supplies, make sure that it is the Apple power brick that is causing the problem. It may well be something else. The signal will most likely change its characteristics if the power supply load is altered in some way. Try a different …
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"Seems the interface is a bit slicker." Not really, it's just different, and has as many "quirks and foibles" as the KiWi (sorry John). OpenWebRX + is more orientated to the VHF / UHF bands, and is good at the modes that can be f…
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There are so many amateur digital modes these days, it is often very difficult to say what is being used. It is around the frequencies typically being used for SSTV, and it could be Digital SSTV, but that is just a guess on my part. The Signal ID Wi…
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I just tried editing mine to lsb for 160, 80 and 40m, by adding "lsb" in the appropriate field in the DX edit menu, and it all seems to work OK.
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Hi Nate, You may find you can obtain better choking performance if you wind the power and RF coax side by side (bifilar) on the cores, with the same number of turns and in the same direction as each other. Some optimisation of the number of turns on…
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All the broadband routers I have had provided, have had noisy Switched Mode "Wall Wart" type power supplies as standard. They produced far more interference than the routers, which generally tended to be of good construction and had been…
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Hi John, Thanks for persevering with this, but I definitely think it was worth the effort. I particularly like the ability to tune using the mouse, but I wondered about a couple of things. I don't quite understand if or how to change the default tun…
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Apologies John, I was using Chrome, and clearing the cookies restored "normal" operation, where it defaults to the mobile site. Regards, Martin
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Thanks John, I'm one of the few UK operators on the band, but we have to use a commercial non-amateur licence. Regards, Martin
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I have an old iPad mini stuck at 9.3.5, and I have to select the mobile site to prevent the keyboard popping up. But it's not a problem for me, as I got used to it. Regards, Martin
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Hi John, Could you also add the 8m band, 40.680MHz dial for WSPR & FT8. Thanks, Martin
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Hi Andy, I understand the points you are making, but having previously discussed this with Philippe, I think there are some valid concerns, that may discourage other people, in other countries, from operating a KiWi. If a simple fix, which John has…
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Check the antenna switch offset value hasn't changed. Regards, Martin
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Hi Rob, I'm not sure which test page of mine you are referring to ? My website hasn't been updated for some time due to various issues, so I don't really have a suitable repository for various bits of information at the moment. Regards, Martin
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The choke and other grounding configurations depend on if you are trying to prevent mains interference from reaching the receiver, or if you are trying to stop noise from a Switched Mode Power supply being radiated. Sometimes you can do both, but ot…
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Sometimes, when used inside a Switched Mode Power supply, the additional choke inductor in the ground (L3 in the circuit) can sometimes be more problematic than useful. I tend to wire the DC 0v / -ve directly to the mains earth, but depending upon t…
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Each of the DXE filters contains two filtered Halo HFJ-1G46ERL RJ45 sockets wired back to back on a small PCB. https://forum.kiwisdr.com/uploads/626/NPS9PQCBI2U6.png https://forum.kiwisdr.com/uploads/459/QP2CXSB202GO.png Pin 10 seems to be left fl…
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Fldigi has a decoder, but I note that there are a number of Linux based parsers and decoders too. Just a quick selection. https://metaf2xml.sourceforge.io/ https://pypi.org/project/pymetdecoder/ https://github.com/soandsoSwEn/synop Regards, Martin
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It's always a problem if folks can anonymously post on the internet, or any webpage using it. A callsign tends to be regarded as a signature, but it is not unique, it's just an alpha numeric string that can be used by anyone, so I don't understand h…
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Hi Philippe, I'd agree with John that it doesn't make sense to list KiWi's that folks can't openly use. But I do understand your reservations, and some countries are definitely more restrictive than others. Short range local VHF / UHF communications…
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I use BktTimeSync (free) with Windows, and set an offset of -1 second, which seems to be good for use with most KiWi's. https://www.maniaradio.it/en/bkttimesync.html Regards, Martin
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A bit more information for those interested in Wave Radars, cut an pasted links from discussions on other sites. CODAR and WERA (now Helzel) are very similar systems, and I think that folks tend to call all of them CODAR, a bit like some brand names…
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They are Wave Radars, and sweep across the frequency range at a rate of approx 4Hz (250mS). The ones you are hearing are most likely located at the Hook of Holland and Dyfamed in France, but there are likely to be other sources as it is a common fre…
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Using opto isolators is sensible, but there is a lot of switching noise on the GPIO lines, that can produce unwanted RF noise. So It's still a good idea to add RC filter networks at the point of exit from the KiWi case. Regards, Martin
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Some previous notes here about using the GPIO port. https://forum.kiwisdr.com/index.php?p=/discussion/comment/7539 Regards, Martin
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I'm also seeing it now too. I have set "Number of simultaneous channels available for connection by non-Kiwi apps" to none, but it is still trying to tune to the 8942 HFDL frequency for ten seconds before it is kicked off. The IP is chang…
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Hi Philippe, The thread is pretty general, so it's easy to become confused. Incidentally, I forgot to mention, if you are planning running two KiWi's from the same supply, as the original question. Use separate inductors and capacitors on the output…