Tech Notes from the Field

Yesterday we had our HTHD+ drop off the air again. When I arrived at the site the mimic panel showed an Exciter Fault!
1. Was it the Flexstar at fault?
Right now we are assuming, between us and tech support, that the PA module in the Flexstar is not happy with something. This is based on a fluctuating forward power of a few tens of a watt while the APC voltage remains constant. To troubleshoot this we await a new PA module for the exciter.

2. Did something else cause the exciter to fault?
What if the IPA is asking too much from the exciter? Seems to be stable and the fluctuations on its forward power follow that of the exciter, so it appears to be working fine.

3. What was the fault?
There is no indication nor have I found log files that would suggest what actually occurred. I need to research to see if the Flexstar keeps any log files. As it is an early “software controlled device” I suspect not or it is well hidden. A call may be in order.

On that note, when I powered up after tests it has remained on the air since. I will deal with the power fluctuations as long as I can maintain legality and on-air. We are a BTC/Navteq station. Believe it or not it is important for us to run HD. We will see if a new PA module actually works. If not, I will suggest a swap of the IPA.