Earlier this month I had been at our Thermopolis transmitter site trying to figure out why the station would often go silent after the top of the hour ID.  I think I finally found it this time!

Towers atop Copper Mountain

My trusty Ford Explorer resting after a long and difficult climb to the top…

More scenery from the base of our tower structure…

While at the site, Reid installs a lock box in the event that we forget to bring a key to such a remote site.

At the top of the equipment rack is our satellite receiver.
This unit is also responsible for inserting the local station ID.
It is the primary suspect at this point for the issue…

IBOC signal generator and aux unit…
Both of these units are also in the signal path and might be at fault.

Testing the integrity of the digital audio signal path with a test set…
Ah HA!  I discovered that whenever the ID was inserted, there was a “glitch” in the digital audio signal.  Normally this would not cause an issue but for some reason it was causing a problem at this site…

Found the problem!  This is the “aux unit” which provides synchronization and switching for the digital audio signal path.  Apparently every time this “glitch” occurred it caused this unit to lock up.

We weren’t able to actually FIX the issue on this visit but at least we now know where the problem is.  The unit will need to be bypassed and replaced on a future visit.