A simple Time Domain Reflectometer

Time Domain Reflectometer PCB Component side

I built the simple signal generator described in Electronic Design. The same circuit you find on ZL1NC and epanorama. Together with an Oscilloscope it can be used to find a cable fault as described in this All about Circuits article.
The 74AC14 SMD is mounted on the board its trace side. All other parts are through-hole. Most parts were salvaged from old electronics. You can adapt the PCB to your needs.

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Wake on LAN

To enable wake-on-LAN over the Internet, the open hardware platform Arduino is used.

Not all routers support wake-on-LAN from the Internet to LAN. This depends on whether you can configure the ARP cache and send or forward a WOL broadcast package.

To support WOL, in this case on an Apple TimeCapsule, an Arduino Ethernet Pro board is used. Thus having a low-power device (Arduino) listening for WOL.

Both the Arduino board and machine to wake-up are connected via Ethernet to the TimeCapsule. The Arduino is powered using the TimeCapsule USB port.

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