I had JUST returned to Laramie when I received a call from one of our other engineers informing me that a listener had called to report (another) outage in Rock Springs.  Great.  Time to turn right back around and make the 3 hour drive once again…

Well, at least I was treated to a beautiful sunset on the way back to the site…

As I got within range of the station, I heard carrier and had a stereo pilot but no audio.  The other station at the site still had audio so I knew it wasn’t the satellite receiver or UPS feeding the equipment rack in this case.  What could it be?  Eventually I made it to the site.

This Digital to Analog converter feeds audio to the main transmitter.  No audio levels and an error indication.  This can’t be good…

Ah ha! Here’s the problem…This device is called an “exporter”.  It is a linux based PC that generates the digital HD signal as well as a delay for the analog audio signal to match the digital.  HD receivers will blend between the analog and the digital signals so it is critical that the two signals are time aligned.  Unfortunately it appears that the exporter has suffered a fault.  Normally it would automatically switch into a “bypass” mode when this occurs but in this case it did not.  It had crashed HARD and was completely non responsive.  Most likely this box will need a new hard drive very soon.

As soon as I powered off the exporter it switched into “bypass” mode and once again passed audio to the main transmitter.

Rebooting the exporter restored normal service.  This is a spectrum analyzer display of the HD carriers.  Since this site uses two separate transmitters for analog and digital, only the digital signal is shown here.

Once again, situation normal (for now).  The travel is wearing on me but I’m always on duty to restore service whenever necessary…

UW88 awaits in the dark…Time to head down to the hotel for the night!