G8JNJ
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Hi, I try and avoid Mini-Circuits if at all possible, because you have to jump through hoops to order stuff, and it takes forever to arrive. Coilcraft is pretty good for transformers and inductors and they deliver almost next day (in the UK). https:…
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Thanks John. All OK now, very strange. Regards, Martin
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Hi John, I've only just come across this thread, but in view of your announcement I just wanted to say a heartfelt thanks to you for initially instigating the project, and for your continued support and commitment to the owners of KiWi hardware. I'v…
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I'd try the choke at 'ground' level, or just after the point at which the the 'ground' wire and coax go in different directions. If they run close to each other they will be at the same RF potential, so you need to isolate the cable carrying the noi…
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Hi John, Thanks that's useful, I'll see if I can figure out what's going on. Regards, Martin
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The plastic tube doesn't really matter too much, because it's still the coax that is forming part of the antenna. The antenna is basically measuring the potential difference (voltage) between the Mini Whip 'plate' and whatever it 'thinks' is the 'gr…
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Hi John, Just one small observation. When the squelch tail option is used in conjunction with pre-record, this seems to introduce a period of muted audio. Maybe the when both options are selected, the squelch tail should consist of un-muted audio in…
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Unfortunately Mini Whips and other E-Probe type antennas tend to be 'noise magnets'. The best solution is to use a balanced antenna such as an active dipole or broadband active loop. As these are much more resistant to common mode noise pickup on th…
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I find that I get the best common mode rejection using a flux coupled transformer, which provides the best results on the lower frequency bands <10MHz, and also add several ferrite sleeves over the coax to provide more effective common mode chok…
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Hi John, Thanks for the latest updates and especially the 'pre-record" feature. I've been using it to monitor some HF aircraft comms today and it's made a world of difference. Regards, Martin
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Hi John, I don't think it needs a huge range of values, so using the same numbers as the squelch tail length would be a good starting point. If you could also manage say 5 seconds, that would be great, as it would allow sufficient time to hear somet…
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Hi John & All, Thanks for this, and the other suggestions too. I have decent sound precessing applications (Goldwave) & Audacity), and I can see signals when they have appeared. The problem is not absolute timing related, but is having to re…
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OK thanks, I'll try these ideas. However, I've got other stuff to do that has become more urgent, so I'll have to revisit this later. Regards, Martin
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Hi All, I'm not overly familiar with Linux, so bear with me as most of this is going to be down to my lack of skill. I've attempted to upgrade one of my KiWi's to Debian10 using John's method. But I have come across a number of problems, that are pr…
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Hi Ben, An interesting method. Incidentally, I had also wondered about having the facility to be able use the internal signal generator to inject an adjustable low level test signal into the receive path whilst still receiving off-air signals. My th…
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Wow, the narrowest CW bandwidth is 6Hz if I drag in both sides of the CW filter passband, and I don't think you would resolve any CW through an even narrower filter. One other suggestion, maybe try using I/Q demodulation and headphones. It has the …
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Hi John, I'm a bit confused. Does the new USB / COM / CAT frequency output show whatever the last frequency change was, regardless of which receiver channel is in use ? or is it channel specific ? If this is so, them maybe just have a /CAT url exten…
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Ah, The Serial Debug port, I forgot about that :-( Good spot. I assume it would need a cheap interface board to provide 'genuine' RS232 levels and / or 5v open collector TX/RX for CIV / CAT interfaces. Regards, Martin.
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Hi John, That's a pity. However I was thinking about this last night and although there are advantages in terms of simplicity in using a locally connected RS-232 port, it would also bring about it's own problems in terms of noise and physical conne…
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Hi John, That's an interesting idea, and one that opens up even more possibilities, and the associated development and support issues :-( On one KiWi site in the UK (Weston http://websdr.uk:8060 ) , we are currently polling the /status url with MQTT…
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Assuming the supply can provide 3A on peaks, then Increase the supply voltage to 5.4v measured at the Kiwi input power connector. There is a slight voltage drop under load within the KiWi and Beaglebone circuit, and increasing the supply voltage sli…
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Hi, It seems to be relative to the centre of the passband, as you have found. Try /-4000,0 for LSB or /0,4000 for USB etc. for asymmetrical filters, that works for me. A single numerical value may only work for double sideband signals such as AM, N…
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Thanks John, I have replied back. Regards, Martin
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Hi John, I've sent an email, as I can't seem to post the console output on this forum. Regards, Martin
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One of mine doesn't seem to want to update. Installed version: v1.553, built Aug 12 2022 11:50:54 Error determining the latest version -- check log And the log shows Mon Aug 15 17:33:36 00:01:10.902 .... L UPDATE: force update check by admin Mo…
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Excellent, thanks again John. My fist simple test is to try for reception of 30 - 60MHz, simply by switching between different external input filters. I'll let you know how I get on. Regards, Martin
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Hi John, Thanks for this. Hmmm, I may simply be tying myself in knots. With 30MHz set as the upper frequency limit. Injecting 40MHz No Downconverter high-side injection or offset selected, brings up an alias signal on 26666KHz (66.66MHz - 40MHz = …
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Hi John, Great thanks for that it all worked fine. However it did show up another problem. How to carry across the associated settings from the associated DX type menu, Band Bars & Band service menu ? I thought about copying the various config f…
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It's a while since I used WSPR in earnest, but I think the WSPR net database has some basic filtering of the raw data to exclude obvious junk decodes and 'strange' callsigns. It may also possibly reject stuff on non-amateur frequencies. Regards, Ma…
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Hi John, Thanks for implementing the "Downconverter high-side injection", very, very, much appreciated. It has also opened up a whole new range of Oversampling experiments to try, such as VHF Airband and 2m reception. By-pass the internal …