G8JNJ
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Everything is inside the box as shown by the dotted line.
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Philippe's comments are valid, but more related to Linear convertors / regulators. This is what I did, but it is for a switching DC-DC convertor running at around 1MHz. https://forum.kiwisdr.com/uploads/733/FPYEAJNKM7UZ.png The capacitors were 10…
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I should have clarified the way it works a bit better. Pushing the mouse wheel down whilst rotating it enables the opposite mode to the default that has been chosen. in OpenWebRX. Having the possibility to tune using the mouse opens up other possibi…
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When using OpenWebRX, the user can define if they wish the mouse wheel to tune or zoom by default, and the opposite action is achieved by holding down the mouse wheel. I must admit that I find being able to swap between the two becomes intuitive pre…
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I'd be tempted to try that one. The roll off is quite steep, and the loss over the amateur part of 10m is not too bad. However, the Comet CF-30MR seems to be an option, as it has a claimed 50dB attenuation at 40MHz. Note not the CF-30S version, whic…
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Unfortunately, a single Mini-Circuits LPF may not have a sharp enough cut-off. Approx. 10dB attenuation at 40MHz and 30dB at 50MHz https://www.minicircuits.com/pages/s-params/BLP-30+_GRAPHS.pdf Regards, Martin
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Ah, I thought that change had been in preparation for some new mode buttons. Wishful thinking :on my part :-) Regards, Martin
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Agreed, it could probably be done with an external browser or other add-on application, although this is not so handy when using different devices. It was only a thought / suggestion, as the idea had occurred to me when switching between AM and NBFM…
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The WSPR net database used to have a lot of problems with upload capacity. !0MHz is one of the more popular WSPR bands, and I wonder if this could be related to the time period after the 2 minute cycle, when the spots are uploaded. I wonder if it …
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Have you got one of the more recent filter plates fitted as your phone line master socket, or are you still using separate micro filters ? Openreach™ MK4 VDSL Plate & NTE5C Master Socket https://www.bttorj45.com/vdsl-adsl-nte-filtered-faceplates…
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I wonder if some of the Plane spotter apps are starting to use KiWi's to aggregate HFDL data, as they already do for ADBS and ACARS VDL etc. Regards, Martin
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The noise squelch is enabled automatically for NBFM modes, but as you have noticed the hysteresis is not brilliant on some types of signals. CB is also bad because you get so many co-channel signals, which sometimes cause heterodynes that 'fool' th…
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Yes it's pretty bad today. My FlyDog sdr SNR score is 11 dB 7 dB at position 541 on the http://rx.linkfanel.net/snr.html list Wessex Flydog - G8JNJ - 0-62MHz - South West UK But I'm usually up in the top ten. Solar noise bursts are also occurring in…
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Ah OK, well done Roger Richard, excellent remote diagnostics, I hadn't thought of that possibility. Regards, Martin Edit - Ooop,s sorry Richard, a senior moment on my part.
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If you already have a signal generator and are not worried about the calibration accuracy. Use CW and measure the peak signal level with the dBm scale digital S-Meter, and compare that against the level of the noise floor with the generator connecte…
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OK I suspect it is related to the CIC filter changes that were made between versions. There was an issue with the original filter causing problems within the receive passband, this resulted in unwanted signals on adjacent channels interfering with w…
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What is the noise floor dBm reading on the digital S-Meter with the RF input disconnected ? Does it vary between software versions ? Regards, Martin
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The Utah Web sdr's have very large antennas, and a complex distribution system with lots of additional filters. This is an example of a distribution diagram for the Northern Utah web sdr's. http://www.sdrutah.org/info/WebSDR_Block_Diagram_1f.gif Reg…
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I'm not sure where you are located, but I think you have been unlucky to encounter this problem. I monitor the VHF Low bands, and would be interested to know what you are hearing. http://wessex.hopto.org:8075 Generally speaking, the Low VHF bands ar…
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The waterfalls may look different if you have used different settings for FFT filter and averaging. The 11.6 dB value in the earlier version I think is derived from the calibration values. So if that doesn't match your 13dB setting, there is possibl…
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I think anything would help, as long as they will handle the current with some margin to spare, but that's what I had to hand. You may have to experiment with the grounding arrangements, to achieve the lowest noise floor. Regards, Martin
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It's still present, if the owner has decided to display the information. Step 2 often reveals what you are looking for, otherwise some detective work is required, such as looking up a callsign on QRZ.com, or searching for other on-line presences. Re…
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I have not observed such a large change Have you tried using the KiWi's internal signal generator to make a comparison between the two versions ? This would rule out most hardware / antenna / off-air signal issues. Regards, Martin
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Audio level adjustment is fairly commonly required, especially when changing modes or bands. How about some form of auto audio / AGC that controls the average level and maybe adds some audio compression to reduce the overall dynamic range, and provi…
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I used traditional transistor, LT1083 and LM338 regulator circuits, but it was the decrete transistor circuit that failed in my case. A lot depends upon what voltage and short circuit fault current is likely to be able to be supplied by the power su…
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Nice build. If you haven't already, please consider installing a simple SCR overvoltage crowbar circuit to each individual supply rail. At some point in the future, you will be thanking me for prompting you to do it. One of four linear power supplie…