Ethernet interface unreliable - very serious problem [fixed with better power supply cable]

fvinkfvink
edited March 2018 in Problems Now Fixed
Hello,

I have trouble getting my KiwiSDR I bought though Massdrop last month to connect to the network, as the Ethernet interface continuously disconnects. After some time the orange LED comes on, after some 20 seconds it switches off, to come back on etc...

The problem is intermittent, sometimes it just works, sometimes it won't I have changed cables, used different LAN switch ports, different LAN switches, different cables, nothing seems to cure the problem. This is driving me crazy! I suspect a faulty Ethernet port, but I am not sure.

Any suggestions?

Frans

Comments

  • bbachmannbbachmann

    Are you shure that nobody else using the same IP-address and that the broadcast address is set correctly?

    Regards

    Bjarne

  • fvinkfvink

    Bjarne,

    It does not show up in the IP address table on the DHCP server. It does not even get that far.

    Thanks for the suggestion.

    Next observation: I booted the Beaglbone without the Ethernet connected: now it does work. I'll need to check whether this is coincidence or a workaround.

    Frans
  • fvinkfvink
    The reboot without the Ethernet cable connected only worked once: It was a coincidence.
  • jksjks
    edited January 2018
    Seeed built a batch of BBGs with bad Ethernet PHY chips or bad RJ45 connectors (not clear which). Unfortunately some of those were used in Kiwi kits. The problem doesn't appear immediately so the Kiwis passed burn-in testing. The problems are as you describe: LEDs on the RJ45 connector not making sense, going dark etc. The PHY chip will also sometimes become very warm, although it is difficult to determine this when the Kiwi board is installed.

    Massdrop only has a 30 day return policy. But Seeed will then step-in and send you a new BBG and pay for the old one to be returned to them for analysis. If all else fails I will send you a replacement personally. So the problem will get resolved but it may take a little time. Thanks for your understanding.

  • fvinkfvink
    Hello,

    I am assuming this is John answering; thanks for your help. I am working with Seeed to solve the issue and have been asked to remove capacitor 162 from the board. If that does not work they intend to exchange the BBG. I will keep you posted.

    Again thanks for the kind offer!

    Frans
  • fvinkfvink
    Hello,

    I removed the capacitor 162 and now it seems to work correctly.

    Thanks for the help, highly appreciated!

    Frans
  • fvinkfvink
    Hello,

    We're back to zero: It is no longer working. this is driving me crazy!

    Frans
  • jksjks
    edited January 2018
    Get a new BBG from Seeed. They should never have been asking customers to be removing components. That is completely unprofessional behavior and I will be speaking to them about that.

    WA2ZKD
  • fvinkfvink
    John,

    I'll see how they respond to my message about the issue returning. Will keep you posted

    Cheers,

    Frans
  • fvinkfvink
    Hello,

    This is getting really annoying. Seeed sent me a new BBG, after I returned the failing one via DHL. Obviously they did not bother testing the replacement. It has exactly the same problem. Since they sent it through Snail-mail I waited four weeks for something useless. This is driving me completely bananas. At least the first one worked for a couple of days, this one shows the failure right away.

    This is crazy. I am now having something utterly useless and irritating for more eight weeks, for which I paid good money.  

    What should I do? Is there any workaround, test anything that could help progress, at least a bit?

    Frans

  • jksjks
    To make sure this isn't a power supply issue, have you tried running without the Kiwi board attached and then seeing if a connection to the Beagle with ssh or a continuous ping is reliable?

  • fvinkfvink
    I have done that as well, I have connected it to a PC port, to a 2.2A apple ipad pro PSU. Did not change anything so far.

    It is getting a bit late here, so I'll continue some trials tomorrow.
  • fvinkfvink
    Hello,

    I had it working for some time. Then to see whether it had 'come to life' I rebooted, and the issue is back exactly the same. I powered down, I removed the kiwisdr and tested the BBG alone. With only one exception that seems to work. (10 trials or so). When I reinstalled the kiwisdr the problem is back. It works one out of ten.
    The PSU I use is a 12W apple ipad pro power supply. I have also used a battery pack 100% charged on a 2.4 A port. i used this pack to power a raspberry pi 3 with LCD touchscreen without any issues.

    I am at a loss.

    Frans
  • jksjks
    This sounds exactly like the cable voltage drop problem we have seen many times. The increased current draw of having the Kiwi board installed is causing excessive voltage drop on the cable from the power supply because the wire gauge is too small for the cable length. This is completely independent of how much current the power supply can provide.

    Normally the voltage drops cause complete power downs of the Beagle because the power management IC (PMIC) on the Beagle sees an input voltage of less than 4.8 or 4.75V and shuts down. But the Ethernet PHY chip and a few other things runs off a secondary 3.3V regulator that might have problems around this lower voltage before the PMIC takes action.

    Seeing these voltage drops can be tricky because they can occur with momentary current increases and so may not be visible with a simple voltmeter that can't react fast enough. If you're using a USB-A to 2.1mm cable adapter we recommend one that uses at least 22 AWG conductors and is as short as possible. Example: https://www.adafruit.com/product/2697

  • G8JNJG8JNJ
    Hi Frans,

    I'd agree with John, all my 'strange' KiWi problems eventually turned out to be associated with the DC power supply and / or connecting cable.

    • No boot from cold
    • Reset button not initiating a reboot
    • Occasional loss of Ethernet connection
    • Inability to save a backup to SD card
    The KiWi can occasionally draw a high level, but very short duration current from the supply and some types just don't like it :-(

    I had to try quite a few before I found one that worked well with the KiWi.

    Regards,

    Martin - G8JNJ

  • WA2ZKDWA2ZKD
    these Acopian remain my favorite


  • fvinkfvink
    John, Martin,

    Thanks for clarifying and helping me to sort this very frustrating issue.
    Maybe it is an idea to make this clear to new users before they buy a cable. Or raise the price 5 USD and deliver a cable with the kit, if it is such a critical part of the solution.
    I guess the safest is now to first make my own cable. If that does not work, I'll review the PSU.

    To be continued!

    Frans


  • jksjks
    This issue is covered in detail in the instructions (http://kiwisdr.com/quickstart/index.html#id-power) But people don't read I guess. 

    We can't supply a cable because what type of connector would we put on the other end? Always USB-A? We don't want to encourage people to use switch-mode power supplies.

  • fvinkfvink
    John,

    You’re right! It is mentioned. I never saw that, so I take the blame.

    Frans
  • fvinkfvink
    FYI - The new cable solved the problem.

    The KiwiSDR has been running for a week now, without any problem. Thanks for the help and this exiting product!

    Frans
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