jks

Hello Brian. You are most certainly welcome here even if you're only a listener to the Kiwi network and don't own any Kiwi hardware. Please let us know if you have any questions.

Donations to individual public Kiwis are always appreciated by their owners. Most of them go to great lengths to site Kiwis in remote, electrically quiet, locations. Usually with expensive Internet connections that the donations help offset.

Your signal (recorded), from my latest standalone version (not merged into Kiwi extension yet) with more decoding:

[00:00:22] [FRQ 0.00] [To: ] [His BER: 3]
[00:00:22] [FRQ 0.00] [CMD] [AMD: "THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG"] [His BER: 3]
[00:00:24] [FRQ 0.00] [Sounding THIS WAS] [From: BAS ] [His BER: 2]

Others (from recordings people sent me), including a DTM:

[00:00:30] [FRQ 0.00] [Call] [From: G8JNJ0 ] [To: G8JNJ3] [His BER: 0]
[00:00:38] [FRQ 0.00] [Call ACK] [From: G8JNJ3 ] [To: G8JNJ0] [His BER: 20]
[00:00:42] [FRQ 0.00] [Call EST] [From: G8JNJ0 ] [To: G8JNJ3] [His BER: 0]
[00:00:54] [FRQ 0.00] [CMD] [AMD: "MESSAGE READS 12345"] [His BER: 0]
[00:01:04] [FRQ 0.00] [Call] [From: G8JNJ0 ] [To: G8JNJ3] [His BER: 10]
[00:01:04] [FRQ 0.00] [CMD] [AMD: "CONFIRM 54321"] [His BER: 10]

[00:00:31] [FRQ 0.00] [Call] [From: SHAEENQ2 ] [To: USMANQ7] [His BER: 1]
[00:00:31] [FRQ 0.00] [CMD] [DTM: "WE ALSO PASSED MSG TO OUR SECTION ALREDY TODAY MORNING ABOUT HOLIDAY HERE"] [His BER: 1]

Not at the lower zoom levels because the waterfall/spectrum sampling is not continuous (the decimation factor is low and the sampling period is only a fraction of the display line time). This of course changes radically above zoom level 10 and I have to overlap when the sampling period exceeds the time it takes to display a line (the decimation factor is huge at that point). It took me forever to understand this because I didn't know what I was doing (some would say that has not changed, lol) and don't really have sufficient mathematical/DSP background.

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Re Glenn's observations and experiments with CM and ground loops: I've been meaning to return to the topic and try and understand the issue in detail because Glenn is obviously a tremendous resource and understands a very important issue. But it needs a good chunk of time which I currently don't have.

The whole situation is confusing to me because of some anecdotal evidence. I don't deny it. I believe in CM. But I don't understand why some Ethernet-based installations have dead quiet noise floors and others are worse than useless. A lot of these quiet installations have photos of their setups in the Kiwi splash screen and they seem to be the typical jumble of equipment in a box with an Ethernet switch, SMPS, cables and other stuff all thrown together. And yet they work great!

What's the difference? Is there a minimization of the Ethernet/antenna cable loop by chance? Something subtle about the ground wiring/isolation? I don't get it. And I wish I did, because then I could make a recommendation to people.

Well, to be fair, the documentation and organization of the documentation are way, way behind. Not to mention that the Kiwi website is straight out of 1994.

You mean in addition to the current password option which allows you to bypass any timeout limitations in effect? E.g. you have a public Kiwi, but for members of the radio club you want them to have a connect limit of 3 hours while the general public gets 30 minutes. Yet a few others have a password that gives no limitations.

From an hp 8657D coupled with a "gimmick" cap. No front panel sweep on the "D" unfortunately (HPIB only). So manual 10 kHz steps. Kiwi spectrum averaging and peak function to capture. Except for < 150 kHz where there is a clear drop-off, the scalloping is probably FFT spectral leakage since I never learned how to do my post-FFT DSP properly.

I see SMPS harmonics that are much louder than the fundamental all the time. Even into HF sometimes. It just baffles me. And when the fundamental is an unstable carrier, at HF it often turns into such a wide signal that the harmonics bridge together and it looks like a huge bump in the noise floor!

It's using a Hanning window now. And the code has the usual suspects available (but commented out): Hamming, Blackman-Harris. I haven't look at the windowing specifically in years. Although we had the recent problems I induced when changing the FFT pixel downsampling and adding CIC filter compensation.

If you're talking about the KiwiSDR Android app, then yes, there was a problem that was just fixed. Kiwis that run the latest release (v1.460) or later should work with the app again. About 70% of public Kiwis have updated. The rest should follow in the next day or so.

The issue was that the app uses an embedded web viewer that did not fully implement web standards that the Kiwi code depends on.

@HB9TMC I'll fix that today. Shouldn't be applying the CIC compensation when there is no CIC in use! 🙄

As for the spectrograms, I don't know. All the Kiwi spectrums I looked at using the Kiwi spectrum display and high averaging gave the same peak values on a variety of settings. I guess the only thing to do is make a new waterfall API option so you can select either behavior and Marco can get his fix for SuperSDR.