jks

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jks
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  • KiwiSDR boot-up - problems?

    It's very difficult to tell, but my first guess is a power supply that isn't supplying sufficient current. If the voltage sags below about 4.7V the power controller on the Beagle will shutdown. That's why the single power LED on the opposite side of the Ethernet connector from the 4 status LEDs goes dark.

    The other thing to try is a re-install of the software from the supplied micro-SD card as discussed above.

    Harri
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    swlaero
  • Help diagnosing interference issues

    Okay, first of all my apologies for not understanding the sophistication of your setup. It is absolutely excellent. Hopefully my long-winded explanation above will help someone else because you clearly understand the issues.

    Now the problem: You've got the worst case of a bad switching power supply I have ever seen. The first clear carrier is on 167.9 kHz @ -66 dBm and appears about every 30.5 kHz up to 30 MHz. The carrier is narrow and stable but has "static" mixed in. This is a classic trait I've seen many times. The UVic beta site had a horrible signal like this around 14 kHz. Fortunately the harmonics died out in the LF spectrum. After almost a year it was traced to a bad power supply in an Ethernet switch.

    The fact that the harmonics go to 30 MHz and are so loud makes me wonder if it's a problem with one of the switchers on the Beagle. Like a bad filtering cap or something. The overall 0-30 MHz spectrum looks similar to the high noise problems we had with an early Element 14 manufactured Beagle. I assume this is a BeagleBone Green? I'd be happy to send you a replacement.

    There is also another huge signal (-56 dBm) at 86.5 kHz that is about 2 kHz wide and has the classic look of a "spread spectrum" (flattop) clock. It has harmonics in the NDB band every 9.5 kHz but dies out at MF.

    KM4YRI
  • Help! display partly dead.

    v1.28, and a few releases afterwards, were completely FUBAR unfortunately.

    g1tvl
  • kiwi.bin fails on PMUX check

    In case anyone is interested I'll explain: For various reasons a user program (one with privileges) cannot directly change the pin mux (PMUX) that determines which device functions and attributes are assigned to the I/O pins of the Sitara processor used on the Beagle. This is specified by device (cape) overlay files used by the kernel and by some other mechanisms. So there is some checking code to make sure the pins are in the state the Kiwi server expects. The panic you saw occurred when one of the unused expansion pins on the P8 connector was detected to have been set as an input with a pull-up rather than a plain input with no pull-up or pull-down. More pins were in unexpected states as shown in the file you attached.

    Now this by itself is not a problem. But the real question is why is this different all of a sudden when there are hundreds of other units out there running without an issue? This is one of the reasons why the Kiwi is shipped with a fixed, known-working Debian distribution. To try and eliminate the side-effects of dependancies like these.


    KA7U