SWLJO43 My KiwiSDR and Problems only with AM, AMN and NBFM Mode

SWLJO43SWLJO43
in KiwiSDR Discussion

Hello,

however, if
I’m receiving AM-Radio stations, I only can listen with USB-Mode. Whenever I’m
switching from USB-Mode to AM or AMN, then the S-Meter goes from approximately
S2 to S9+10 and I’m hearing the AM-Radio station very weakly, as if they are
being inhibited. L

Nearby,
only 10 km away, as the crow flies, is a local FM 10 Meter Repeater (DF0HHH).
Similar phenomena happen, whenever I’m switching from USB-Mode to NBFM, then
the S-Meter goes from approximately S4 to S9+10 and I can’t hear the repeater
at all. L

I’ve tried
the following:

  • Erasing the browser caches
    (Edge, Chrome, Firefox) = no result
  • Restarting the beagle and the
    KiwiSDR = no result
  • I’ve inserted a resistor
    between the antenna and the KiwiSDR to reduce the OV = no more red OV
    indication
  • I’ve shortened the Boni-Whip
    Antenna from 10 cm to 1 cm = no result

Do you have
any Idea what I’m doing wrong?

Dirk
(SWLJO43)


S-meter graph with -60 dBm = AM or AMN or NBFM (is the problem)

S-meter graph with -120 dBm = LSB or USB 


image

Comments

  • jksjks
    edited January 2017
    Hi Dirk,

    Yes, I know exactly what has happened. Someone has pushed the "IQ bal" button on the IQ display extension while the Kiwi was not tuned to a quiet, signal-free part of the band (or better yet while having the antenna disconnected). You know how you can tell? Tune to an AM signal in AM mode. Then tune away some amount. If you hear a carrier then there is IQ imbalance. You would expect to hear the carrier in sideband mode but not in AM!

    I have fixed the imbalance on your Kiwi.
    In theory only a Kiwi admin should be able to use the IQ bal button, but maybe there is a bug with the checking so I'll look at that. [Update: yes, there was a problem. Fixed in the next release.]

    These discussions explain why there is an IQ imbalance problem in the first place:

    Here is another way to demonstrate the problem. Bring up the IQ display on an AM signal and adjust the gain. If the IQ is balanced the display should be centered in the crosshairs. Yours definitely wasn't.


    image

    Attachments:
    https://forum.kiwisdr.com/uploads/Uploader/ef/b3d83ab633646ef896ad6372975d67.png
  • SWLJO43SWLJO43
    Wow that helped. I openend the IQ display, tuned to an AM Radiostation and realy the dots are not centred. On click on the yellow IQ bal and my problem is solved.
    Many thanks and greetings from northern Germany.
    Dirk SWLJO43
  • SWLJO43SWLJO43
    Hint: whenever i'm change the value in S-meter calibration, than i have to click on the yellow IQ bal button again.
  • jksjks
    Yes, until I fix the bug I found the values set with the IQ bal button don't get stored correctly in the persistent configuration parameters. So when you do something that reloads the configuration you lose the latest IQ balance. Hopefully I can release a fix for this tomorrow.

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