[Skimmertalk] My QS1R died during CQ WW CW

[Bob Wilson, N6TV]

Update:  local SDR expert WA6KBL determined that the 1.2V voltage regulator
chip on my QS1R board, which feeds the FPGA hardware, seems to have failed.
  The measured output voltage was only about 0.8V.

Apparently this is not the first time this chip failed when someone was
running Skimmer Server, which really taxes the hardware.  This chip gets
really hot.

WA6KBL is going to experiment by replacing it with a different voltage
regulator, perhaps one with a heatsink bolted to the side of the case.  If
anyone has already gone through this exercise, or added a cooling system to
the QS1R, please share.

I'm encouraging WA6KBL to write up the modifications once testing is
complete.

73,
Bob, N6TV

On Tue, Dec 2, 2014 at 8:21 AM, Bob Wilson, N6TV <n6tv at arrl.net> wrote:

> It appears that my QS1R had a hardware failure just after 0947z November
> 30th (during CQ WW CW), after it ran Skimmer Server continuously for a
> couple of days.
>
> Rebooting Windows and power cycling the SDR makes no difference.
>
> Skimmer Server reports an error and repeats "Reloading FPGA."   CW Skimmer
> reports "FpgaCommand/usb_control_msg failed."  HDSDR reports "Cannot read
> from SDR".
>
> The red PWR LED on the QS1R is lit, and the USB device is detected OK by
> the Windows device manager (under "libusb-win32 devices/QS1R Direct
> Sampling Receiver", so I suppose the power supply is OK (it's the 2A
> supply).
>
> Maybe it overheated?  Time for a new QS1R board?  It's an older one, not
> of recent generation.  Has anyone else on this list experienced a similar
> failure?
>
> 73,
> Bob, N6TV
>