v1.360+: DRM extension now available



  • I put drm in the extension part of the DX tag and that worked.
  • when I just did it, the audio muted but the DRM screens did not appear. (v1.362)
  • Selecting 'DRM' in the mode menu of the DX tag is what's broken (and I've just fixed for today's update).
  • jksjks
    edited December 2019
    What happened to AMN mode? Please bring it back!
    A few people have asked this. I neglected to mention that the mode buttons are now "cyclic". I.e. when you click repeatedly they cycle through their available options. Because of this there are now 2.1 kHz wide passband options for the original 2.4 kHz wide USB/LSB called USN/LSN. And a placeholder for synchronous AM called SAM.

    This change was necessary to add the new options without making the control panel any larger.
  • Just joining the show here -- but what is SAM?

    Many thanks -
    Colin - VA7WWV WebSDR KIWI - Victoria B.C. Canada kiwiwebsdr.dxer.ca
  • SAM=Synchronous AM, an AFC scheme essentially
  • jksjks
    edited December 2019
    'Synchronous AM', an alternative AM demodulator that has certain weak signal detection advantages (and probably others, I am no expert). In SAM mode you add a PLL that locks to the AM station's carrier and then use the PLL output to drive a product detector (normally used in sideband mode detection).

    Fun fact: you can hear how far off an AM BCB station's transmit carrier frequency is by using a GPS calibrated Kiwi and listening in IQ mode. How fast the audio "moves" from left-to-right in your headphones is proportional to the station's carrier error. Hence why SAM needs a PLL. Of course you can use the IQ extension if you want to see this visually instead.
  • Observation: coincident with the DRM changes I am suddenly seeing people connect and have the SSTV extension invoked, but places where there would never be SSTV... bug?
  • edited December 2019
    Anyone else notice DRM no longer working (doing anything) on their KiwiSDR? I think this started with the 1.361 update. If I select DRM mode, nothing appears in the graph, IQ display etc. Just blank.

    EDIT: Rebooting the Kiwi seems to have fixed that. Seems like a restart was not enough.

    EDIT: And... it's stopped working again.

    EDIT: And... it's working again, without changing anything. Strange.
  • edited December 2019
    Hi Chris,

    It's working OK for me.


    EDIT - The drm flag in the url doesn't bring up the extension.


    Martin - G8JNJ
  • Yes, using "drm" as the mode in "f=" seems to do nothing, e.g. "/?f=3965drm" whereas specifying DRM as the extension is fine: "/?f=3965&ext=drm".

    I'll fix this. DRM is unique as a mode in that it opens an extension. All the places a mode is used have to check for that case (and I missed one).
  • Thanks for this extension! Great work!! Regards, Jari OH6BG
  • Dunno if this was noticed, but I wasn't able to run the DRM extention if I happened to be in an RX slot other than RX1, even if I was the only user.
  • jksjks
    edited December 2019
    wasn't able to run the DRM extention
    What do you mean exactly? Did the extension panel come up and show its message in yellow about needing exclusive use? Did no panel appear? Something else?

    Since you ended up on ch1 that means ch0 was "busy". There is a period of time when a new connection has taken a channel but not completed enough of the API handshake to cause an entry to appear in the user list showing the details. Also possible are some of the very short term connections like the various SNR measuring services that don't stay connected long enough to show up. I think your Kiwi is one of the publicly listed ones so these two situations are possible.

    Update: I added code to force ch1 to be used every time. It worked fine.

    This will no longer be a problem in a few days when I re-enable normal connections even while DRM is running.
  • jksjks
    edited December 2019
    v1.363 adds a scrollable station schedule timeline. Click on the blue segments to tune. Small-screen devices are not well supported at present.

    The schedule data is fetched from kiwisdr.com when the extension is opened. So the possibility exists for it to be dynamically updated, although this is not currently the case. If kiwisdr.com cannot be contacted (e.g. a Kiwi with no network connection) a built-in schedule is used. Your updates and corrections would be most appreciated. Either here or to support@kiwisdr.com

    The vertical lines are, left to right, 0:00 - 24:00 UTC (one per hour) and the red line is the current UTC time. The red line will move across the display automatically.

    Some other minor changes:
    • sdr.hu will show an icon if DRM is possible (extension is enabled and Kiwi is not is 20 kHz mode). The user limits still apply.
    • Clicking on a DX tag with mode set to DRM will now open the extension.
    • A little more text was added to the help panel.

  • Since you ended up on ch1 that means ch0 was "busy". There is a period of time when a new connection has taken a channel but not completed enough of the API handshake to cause an entry to appear in the user list showing the details.

    That may be the issue I was running into. I'll give it some more time after the last other user leaves. Or is shown the door :)
  • >
    >This will be a long update as a new compiler is installed and the DRM code takes 10 times longer to compile than the rest of the Kiwi code. The DRM compiled code >is cached so future updates won't take as long.

    I notice that it's still taking a very long time (maybe up to 1/2 an hour) to perform updates even between the most recent versions e.g. v1.361 to v1.363

    Could be what is catching out folks who are trying to initially setup or manually upgrade a KiWi ?


    Martin - G8JNJ
  • edited December 2019
    I've got The DRM extension running on 11695KHz and have a good signal, S5-7, but the audio won't lock. I have IQ feeding DREAM 2.1.1-svn808, faad2_drm.dll, on Windows 10 decoding 100% of the audio, sounds great. Both systems are using Chrome, one on Linux, one on Windows. The IQ to DREAM is windows, the DRM extension is Linux, both on my LAN, http://ka7u.no-ip.org:8073 This KiwiSDR is using the BBAI currently just serving my two screens.
  • v1.364 improves the DRM UI for mobile devices and small-screen devices in general.

    For the narrowest screens (e.g. iPhone-5 in "portrait"/"candy bar" orientation) when you select DRM mode only the station schedule is shown. To get back to the Kiwi control panel close the schedule by touching the close icon ("X") at top right. Normally this would stop the extension. But in the case of DRM it keeps running until you select another receiver mode ("AM" etc.) To see the schedule again just press the DRM mode button (even though it is already illuminated green). The same will happen if you touch a DX tag that has its mode set to DRM.

    On medium-sized screens (e.g. iPad or larger phones) you'll get the DRM and Kiwi panels side-by-side. The DRM panel will scale as the screen is rotated.

    There are still a number of known problems (e.g. the schedule font size is often too small).
  • @Ron It's quite possible there are performance differences. I have not done side-by-side tests yet since it is difficult to do from here (no reception). I need to get shell access to more test Kiwis in Europe. I spent a long time chasing what I thought was a bug in the v1.364 release just now. Only to find it was the Internet connection at my UK test site that had turned to crap, causing all the drop-outs.

    To get Kiwi DRM and Dream at the same time, are you using an AI and sending IQ mode audio to Dream via a second Kiwi rx connection? So that the Kiwi has two channels listening to the same frequency?
  • @jks Yes as you wrote, using an AI, I'm using the same KiwiSDR both channels on the same frequency. I started testing this after failing to get an audio lock on what seemed to me to be a good DRM signal using the DRM extension. I usually use an openSUSE Linux OS computer but I do have a Windows 10 computer on the adjacent table that has the DREAM receiver. So I started another instance on the KiwiSDR on that computer and the DRM decoded fine from the IQ feed. So then I let the extension run on one and the IQ feed on the other. The IQ feed played solid, the DRM extension had intermittent locks, but nothing solid. Next time I get a decent signal, I'll try again but this time using the Windows computer for the DRM extension. I don't currently have DREAM on the openSUSE computer. Newer OS doesn't have it in the repository.

    The DRM extension station directory is very nice!
  • edited December 2019
    Anyone had any luck with the WINB DRM Single Channel Simulcast (SCS) transmissions ?

    This one's on 13692.5KHz and is putting quite a good signal into the UK.


    Martin - G8JNJ
  • Hi John & All Happy New Year to everyone.

    Even if it's not possible to decode DRM because the KiWI is occupied, could it be made so that you can still open up the DRM schedule screen so that you can select and tune to stations to see if they are transmitting DRM, even if it's not possible to decode it at the time ?

    Also if the DRM extension is selected but the KiWi is occupied, could the DRM extension wait and reserve a slot, but start working when the KiWi has become clear for use ?


    Martin - G8JNJ
  • Happy New Year 2020 and best wishes to all!
    @jks If you need to test the DRM extension, you can use my http://dacha.swl.su:8073 based on BB-AI, I do not publish it on SDR.hu, because there are many local QRMs, but some DRM stations from India, China and Romania sound good ...
    Thanks for the grate job!

  • @Martin @Yuri
    Thanks. I'll take up your offers to use your Kiwis soon. I'm trying to get an update out where the admin can set the number of allowed "ordinary" connections when DRM is active. This will allow me to run DRM on a remote Kiwi and simultaneously collect an IQ stream from a second connection to send to Dream.
  • do we forsee any other variations in "channel number and type" for the AI based systems?
  • My headstone: "Hey, one more thing before you go.." :/
  • Having great reception on RNZI @ 11690KHz this morning. I even managed to receive it with 2 instances of DRM extension running on the BBAI @ 1GHz, although it was a bit intermittent. But with the DRM extension and the IQ extension feeding DREAM, I was easily decoding 100% audio from two slices of the same KiwiSDR on two different computers. It was interesting to notice that the DRM extension was the echo and not the DREAM / IQ stream. So my report today, the DREAM / IQ stream is able to decode a weaker signal 100% than the DRM extension, but given a decent signal, the DRM extension does great.

  • edited January 2020
    About WINB. Strong signal @9265 at about 1140Z. S9+10. Tune to 9267.2 and trim lower sideband (see attached screen shot) and get a solid signal, although I can't say I enjoy the programing. My experience is that you usually need a S9+ signal for reliable decoding. Now if I can only find something worth listening to.....
    Thanks so much for this addition. It is great fun.
    BTW, what is on the other sideband? Does not look like AM.....

Sign In or Register to comment.