Repeater & ECHOLINK Stuff

As SYSOP of our local repeater (see )  which is located on our BRUGES Belfry, about 85m high and reachable by 365 stairsteps to climb, I developed some accessories for our ECHOLINK facility (see

Watchdog for ECHOLINK PC:

Our ECHOLINK is running on some SIEMENS industrial 'Box-PC 620', a very reliable machine, linked to a link transceiver located at the repeater site. We choose for this approach - not linking directly to the repeater - for additional reliability and possibility to exchange the repeaters when maintenance is required. This was off course possible due to the fact that Internet is available at our site !   The link transceiver is an old  defective IC-2725 with burned out final stage, modified so that it is still able to give 10mW output on 2m. It is powered from the PC, so that the complete unit is modular.

This very robust BOX PC-620 has the annoying feature that it cannot be rebooted from Windows : if you give a 'shutdown and restart' command, it will shutdown and then remain in some 'sleep'  stage, a cursor flickering on the screen.  The only way to have it rebooted is to disconnect and re-apply the AC power supply, or depress the RESET button. Not very handy as it is in a remote location !

Therefore a hardware watchdog circuit was designed, based on a PIC circuit and firmware developed by ON7ATV (thanks Alain!). The circuit is powered by the USB port of the PC (5v), the output is connected to the RESET switch (interfaced by an opto-coupler), and the input is linked to a serial port of the PC.



By means of a scheduled task, triggering a simple DOS batch routine at regular intervals, a small  stream of data is outputted on the port, thereby resetting a counter on the PIC board.  If no stream is received (this means : a signal of constant level, either 0 or 1), the PIC board will eventually close momentarily the opto coupler and generate a reset.  The timings are adjusted so that no subsequent reset happens in a boot-up phase.

Off course this circuit will as well monitor should the PC become 'frozen' and initiate a brute force reboot.


WatchGuard  for ECHOLINK DTMF-control:

Our new ECHOLINK facility is being intensively used and tested. As some weird (and mostly same) DTMF codes are given which  invariably produce the same error message ( code 'xxxxx' not found'), some kind of filtering was needed to discourage these 'test' !

Unfortunately, there is not such facility in the standard ECHOLINK software. However, the ECHOLINK software offers an API interface by which some interaction is possible.

Instead of designing an application in Visual Basic, I choose for the 'direct approach' using VBscript, which can be edited very easily to suit your needs.  The script will run in background under following conditions:

Remarks :

Download the script

Download a DTMF test script  (it simulates DTMF codes send to ECHOLINK, you can define the code in the suffix of the command line. As this is simulated, even when DTMF decoding is disabled, it will still send & virtually decode !) 

Dowload a Speechtest script (producing the 17 messages built in ECHOLINK)