New KiwSDR can't access local Browsers [fixed, power quality issue]



  • Thank you for the reply. It's late here, and I'm tired, so I will pause for now and follow your prescribed steps tomorrow.

    Thanks for all your help again.

    -Zyg- AF4MP
  • edited February 2020
    For the interested watchers..
    What power supply are you actually using (voltage and current)?
    Does it have a decent 5.5mm/2.1mm plug on it?

    Only reason I ask is that many of us have tried unsuitable power supplies that allow the voltage to dip too low on boot, often that is not helped by the plug being a 5.5mm outside but having a too lose an inner connector (E.G. 2.5mm).
    When you try booting, is the assembly just Kiwi+BBG? (no antennas, or other connected USB devices).
  • >What power supply are you actually using (voltage and current)?

    I started off using a 10000 mAH LiPo USB Battery Bank (used for charging cell phones) having a 5.0 V 2.4 A max output.

    I thought that might be part of the problem and changed to a LiFePo4 12v / 3.3Ah / 42 Wh battery with a 15 W DC-DC 12V to 5V convertor having an output 5V at 3A max.

    No noticeable change in performance between those two batteries.

    The Kiwi felt warm after a couple of hours of use.

    As of yesterday I have a new BEL 5V 3A supply (recommended by KiwiSDR) that I will wire up and use.

    >Does it have a decent 5.5mm/2.1mm plug on it?
    Yes, and it fits nice and tightly in the socket.

    When you try booting, is the assembly just Kiwi+BBG? (no antennas, or other connected USB devices)
    I had the GPS antenna attached and then took it off - no change.

    After wiring up the BEL supply I'll have to figure out how to ssh into the Beagle and use the commands.

    Thanks again for all the suggestions!

    -Zyg- AF4MP
  • From other threads you may have seen, but it is worth repeating, be a little generous with the 5V, I.E. if the Kiwi sees 5.3V at the barrel connector that is OK, 4.95V not.
    Most supplies dip under load before regulation, the Beagelbone does not like that, especially booting from a marginal start (remembering the 5V input is fed through DC filtering components).

    I have the dubious honour of supplying the "most criminally over voltage supply, for the longest time" before my first Kiwi silently closed down, the design is surprisingly tolerant of over voltage but less so under.
    That one is still working BTW, I just reduced the voltage and rebooted, it held no grudge. (it was well over six volts by the way).

    For SSH under Windows Putty is a reliable and efficient solution.
    Linux "ssh debian@yourkiwiIP or root@yourkiwiIP" works or get fancy with Termius etc.

    Good luck

  • Stu, thank you for the info.

    The lower than 5V may very well be the problem. I missed the lower voltage threads. :s

    The battery end of the 2ft. cable to the Beagle measured 4.90 V when I checked it this morning. I was more concerned with lower noise, hence the use of the battery, rather than a slight voltage drop. I know that the Raspberry Pi, for example, can tolerate a lower voltage of 4.55 but not that much above 5.25.

    I also have a used Acopian 5V 200mA power module that if it still works has, apparently, slightly better specs than the BEL.

    Now I have to make up some cables with fuses etc. for the power supplies.

  • Zyg, I use a Bel Power myself, one 3A to feed two Kiwis. I adjusted the voltage to 5.2VDC after reading about possible issues with "too low" voltage. There is a pot on the power which lets you adjust the voltage.
  • edited February 2020
    I got caught with under voltage and only then did I read the posts about it and the setup instruction advice (sorry John).

    Myself and others have used the tiny DC-DC adapters (LM2596), the smallest have variable potentionmeters that are a bit too course, or too easily knocked, for long term trust but the ones with multi-turn pots stay on voltage and are surprisingly low noise except LF obviously.
    Other DC-DC step down adapters I have tried, even £60 "Big Brand"ones seem to exibit higher HF wide noise.

    I like the DC-DC when doing various tests or remote powering as I can safely throw most linear PSU's I have here at the adapter knowing the Kiwi is safe.

    For best noise obviously a fully linear supply is preferred and if you tweak your Bel voltage up a little and use good wiring it should be excellent.

    On the Raspberry PI I was watching the log of one the other day, running from the same supply at the Kiwi (indicated 5.3V) the log kept reporting under voltage events. I tweaked it up a little, I didn't know the PI had such a limit on the upper end. Just checked, my not exactly cheap "Nobsound" (no, really) Chinese supply is actually now putting out 4.9V at indicated 5.3V. Must have aged as indicated/output was much closer when I bought it.
    You have just helped me with that confusing PI error message, thanks.


    BTW on the Acopian I assume you mean 2000mA (edit is under "options" top right)
  • I gave up on all those "eBay grade" new supplies and bought Condor linear units which can often be found used on eBay
  • Bjarne, thanks for the tip about the pot, I will also adjust the BEL voltage to make it about 5.2V.

    I'm going to put up some new antennas, or rather put down, a "loop on the ground" antenna that will probably need a low noise pre-amp - hence my recent collection of power modules.

    I have a small Acopian 15EB20 power module that is 15V @ 200 mA slated for that purpose.

    The 5V Acopian, you are correct Stu - my typo, is rated for 2 Amps and the model number is 5EB200 (they can be found, used of course, on Ebay for much lower than the brand new price):

    The output voltage can be adjusted per Acopian instructions:

    factory set to within ±1% of the nominal output voltage
    rating. (AC input models having outputs of 1 to 9 volts,
    within 2%.) If necessary, single output models can be more
    precisely calibrated to the nominal value by the use of an
    external trim resistor connected between the T/C* pin and
    one of the output pins. With certain units, connecting the
    resistor from the T/C pin to the (+) output pin increases
    , and connecting to the (-) output pin decreases it;
    with other units, the reverse applies. Begin trimming with
    approximately 1 megohm resistance, and decrease
    resistance until calibration is attained. Do not use a
    resistance value of less than 20K. Trimming the output to a
    voltage other than the nominal rating may adversely affect
    performance and may result in damaging the supply.

    Haven't had much time to work on this today.

  • I have used those Acopian, bought used on eBay. I now use Condor supplies. Both work well.
  • ZygZyg
    edited February 2020
    Well I just installed the new BEL power module in an old computer ATX power supply case, adjusted the output voltage to 5.2V and plugged in the KiwiSDR.

    When checking I received the following message:

    Beginning to look good!


  • My KiwiSDR now works well even with the long wire antenna on the ground, in several broken pieces, after a recent storm!

    Didn't have to do anything (SSH) to the Beagle just plugged in the power and it immediately started to download the software update.

    The original BeagleBone green has no problems and therefore I will not take advantage of the kind reimbursement offer. I need to find a good deal on a barefoot KiwiSDR board to go with the lonely Beagle!

    Thanks for all the help it has been sincerely appreciated.

    Now I have to go and work on getting my Linux Dream program to decode xHE-AAC just as the KiwSDR does!

    -Zyg- AF4MP
Sign In or Register to comment.