Quick aside – concatenating PDFs with Ghostscript

A useful little snippet.  This will concatenate multiple PDFs together into one;

gs -dNOPAUSE -sDEVICE=pdfwrite -sOUTPUTFILE=firstANDsecond.pdf -dBATCH first.pdf second.pdf


TP-Link TL-POE10R PoE Splitter Ground Loop Issues!

A warning for those who are setting up PoE gear (like I’m researching).  The TP-Link TL-POE10R (a low-cost voltage switchable PoE splitter) has a fairly major issue.  It’s not galvanically isolated.

This means that if you power a device using the splitter, and that device has a non-isolated electrical connection to something that’s independently powered, you may get a ground loop.  This will usually manifest itself as the PoE injector shutting down, but may manifest itself as anything from shorting out components to starting a fire (extremely unlikely).

NOTE – This is not an issue if you have no non-isolated electrical connections going from the device attached to the splitter.  So if you have a Raspberry Pi attached to the Ethernet cable on the splitter and being powered by the splitter you’re cool.  But if you plug an HDMI cable from the RPi going into a TV while it’s being powered by the splitter, sparks may fly.

The solution is to either be careful, buy a proper isolated splitter, or use a DC-DC isolating converter.

Reference article here.

OpenELEC 4.0 Released (XBMC 13.0)

With the release of OpenELEC 4.0, XBMC 13 (Gotham) is now available!  For those of us driving a media center with a Raspberry Pi, this is great news (there’s significant performance improvements on the RPI).

Anyhow, it turns out that the upgrade process from OpenELEC 3.x is extremely simple.  Just extract the downloaded package, and in the target folder you’ll find four files – KERNEL, KERNEL.md5, SYSTEM, and SYSTEM.md5 .   Using Windows Explorer, browse to your media center (eg, \\mediacenter), and drop those files into the upgrade folder.  Reboot the media center, and it automatically upgrades.

On mine, there were a few PVR addons that enabled themselves I didn’t want, so I just disabled them and rebooted again, and all appears fine.

GT-i9305T CyanogenMod Nightlies changed to CM 11

Be warned!  As of Christmas Day, the CyanogenMod nightlies for the GT-i9305 series have changed over to CyanogenMod 11.


Go hit this thread for info on the packages you’ll need.  You will need, at minimum;

  • ClockworkMod (from that thread!)
  • cm-11 Nightly Build (from get.cm will do)
  • gapps-kk build (from that thread)

Then, in order to make it work, flash things in this order;

  • Reboot your phone into recovery mode.  MAKE A BACKUP.
  • Flash the ClockworkMod ZIp.  Reboot again.
  • Flash the cm-11 build
  • Flash the gapps-kk build
  • Wipe the cache partition.  Reboot.
  • Pray

Good luck!

cm-10.2-20131022-NIGHTLY issues

Upgraded my GT-i9305T to the latest CyanogenMod nightly, and had quite a few issues. Namely, my phone would no longer connect to 3G/4G, and the APN settings were blank.  Trying to re-enter APN settings didn’t work (nothing would go into the APN list!).  I tried rolling back to a previous nightly, but then the phone just kept rebooting.

The solution was to install the nightly above, and then reboot into ClockwordMod and clear the cache.  After I did that and rebooted, my APN settings were normal and I connected to the data network without issues.