v1.813
From the CHANGE_LOG file:
v1.813 June 14, 2025
SNR measurement changes: (thanks VA3ROM et al)
Additions to admin control tab, SNR section:
New measurement intervals: 1, 5, 10 minutes and custom interval.
Remaining minutes to next measurement shown.
One custom band definition with frequency/zoom fields.
Checkbox to also measure ham bands and AM broadcast band.
Checkbox to force measurement after an antenna change.
Discussion:
The custom band, if setup, is added to the current default bands appearing in the
my_kiwi:8073/snr query JSON result. There is no user interface feedback if you enter
invalid values into the custom band fields. So check your combination of freq lo/hi and zoom
carefully to make sure they result in a freq range that fits entirely within a single
waterfall span. Otherwise the custom band will be ignored and not appear in the JSON result.
The ham/AM band checkbox adds all 12 ham bands and the AM broadcast band to the JSON result.
The ITU setting determines the upper freq limit of some bands (e.g. 40m 7200 vs 7300 kHz,
AM BCB 1602 vs 1700 kHz).
When "measure on antenna change" is active there is a 5 second delay after the last antenna
selection before the measurement starts.
JSON output changes to the /snr URL interface:
The measurement interval field "ihr" (hours) is now "imin" (minutes).
A new field "ant" shows the antenna that was selected when the measurement was made.
A value of zero means antennas are grounded or the antenna switch is not configured.
Note that for antenna mixing setups only the last antenna switched is given. Not all the
antennas cumulatively.
Changes to support camp mode by kiwirecorder: (thanks Ben)
You may know that when all channels are full, and you try to connect, you are presented with
a camp/queue panel that allows you to "camp" onto another listener's channel and hear what
they are hearing. But without being able to control anything (except volume/mute).
Kiwirecorder now has this capability. Changes were needed on the Kiwi side to support this.
The envisioned use case is as follows. You have an application running on another computer
that processes streamed audio via the netcat option of kiwirecorder. But you want to use
a regular Kiwi connection and its full user interface. You just want the netcat stream to
"follow" what the Kiwi UI is hearing so your external application can process the same audio.
An example of such an application might be a modulation classifier that could never run on
the Kiwi itself due to the limited processing power of the Beagle. To achieve this you
simply tell kiwirecorder which Kiwi channel number to camp on. In camp mode kiwirecorder
will do this instead of making a new, separate connection to the Kiwi. Communication over a
separate stream back to the Kiwi with application results is still to be implemented.
Fixed problem with Debian 11 upgrade function on admin backup tab. (thanks 2E0SXX)
DRM extension: Improved sorting when station schedules are displayed by time.
Fixed bug preventing timezone setup when only source of lat/lon was IP address geolocation info.
Comments
Hi John,
Could you kindly explain how and what this function does and works?
"One custom band definition with frequency/zoom fields"
I assume it allows SNR measurement of a specific frequency range, however I am not sure on the Zoom bit, and how that then contributes to your SNR values.
Interesting observation when looking at high snr NZ kiwis SNRs and it looks like this
About the "Custom band" fields:
SNR measurement uses the waterfall, although it's easier if you visualize it as using the spectrum. All those spectrum "bins", which originally start in frequency order, are re-sorted by signal strength. Then the 50% bin is taken as the noise floor. The 95% bin is taken as the highest level signal (the remaining 5% ignored to remove super strong outliers). The difference is the SNR. An approximation for sure. But that's what we have.
Now when you measure a custom sub-band you need it to occupy a large part of the spectrum so lots of bins are visible and available for the SNR computation. Just as you would if you were trying to view it in the user interface. And that requires a zoom level appropriate to the start/stop sub-band frequencies you want to use. If you left the zoom at zero (0-30 MHz), and you wanted to measure the 30m ham band, you'd only have a few bins available that covered that frequency range. Not much for the SNR computation to work with.
So, to figure out the correct zoom level to enter do this: With a regular Kiwi connection enter the center frequency of your custom band as the current frequency. Zoom all the way in. Now zoom out one step at a time until both the
lo
andhi
values of your custom band just fit in the waterfall/spectrum. Use the zoom value "n" from theWFn
button on the user control panel.Results from custom band measurements, as well as from the "Also measure ham bands and AM BCB" checkbox setting, are only available from the URL query:
my_kiwi:8073/snr
(adjust actual Kiwi name/port as necessary). They are not currently displayed in any Kiwi admin or user web interface.---
Your image happens to fit the definition of a relatively large SNR value due to so many high valued bins plus many bins that are very low valued at the higher frequencies (very bad VDSL RFI in that image). Even though there are practically no useful signals outside of the AM BCB. That's just the limitation of the SNR algorithm.
Something odd happens with DigiSkimmer (which is using kiwirecorder):
When I start digiskimmer, it should make 8 connections to two kiwisdrs. But it doesn't seem to make the first two connections (the first one on each kiwi). They don't show up on the kiwis.
When I restart the kiwi-server while DigiSkimmer is still running, DigiSkimmer is applying a timeout to re-try to connect. After the kiwiserver is restarted, all 8 connections are working as intended.
It's maybe a problem with how DigiSkimmer is setting up the kiwiclient connections (too many at once?) I can't point out the problem right now. This wasn't a problem before 1.813 AFAIR.
Hi all, John,
I think there's a little issue when one connects directly on the camp panel from URL for v1.813.
The first time you click on the "Enter Queue" button, almost nothing happens (try it to see what 'almost' means). The next time you click, you can finally enter the 'User page'.
73, Thierry
@F5AFY Yeah, I see that. Not sure what's going on yet. Thanks
Okay, got that fixed for the next release. Had to implement kiwirecorder camping is a slightly different way.