Friday, October 8, 2010

Watching the KCUR TX

Day 3 of the barnraising will come in due course, but I want to talk about something more recent first.

Recently, Robin took a well-deserved vacation - in fact, he went on vacation at the same time as I was at the barn raising, though he was gone for longer. At any rate, while he was gone (and I was in town) I got to take care of the transmitter. This involved putting my number as the first one in the transmitter remote's call list, getting the password to the remote control, and a set of keys. I also received a spreadsheet of what monitors were connected to the individual channels on the remote (a Burk ARC-16), so that I knew which channels did what.

In the time that Robin was gone, the transmitter did not blow up, and KCUR did not go off the air. Thus I am counting my first time as being the person in charge of the transmitter a success. However, I could have done a fair sight better, I think, and I plan to do better next time. First of all, voltage. A couple of times I got calls from the transmitter saying that the voltage was low. I cleared the alarm, and figured that since the transmitter didn't call me again after I cleared the alarm, the problem was transient and nothing to worry about. In fact, it was not a transient problem, and when Robin got back he had to call KCP&L to get the voltage back to where it should be. Additionally, this low voltage situation was causing the transmitter to operate inefficiently, causing the room to be overly warm. There was also a problem with the HVAC - the air conditioning wasn't blowing cold air. I got calls from the transmitter once or twice warning that the temperature was above the set level, but again, since the transmitter didn't call again after I had cleared the alarm, I figured it was a transient problem. Ultimately, it was an error in my thinking: these "transient" problems were still problems that warranted investigation.

I also went over to the TX last Saturday, while Robin was gone, to try and get VINA, an organization that leases a 92kHz subcarrier from KCUR, back on the air. They had sent a box of equipment to the station for us to install at the transmitter in place of the equipment they had been using. During the week I had been out to the TX to replace the satellite (they get their signal via a Ku band satellite downlink) receiver they were using, but that wasn't enough to get them back on-air, so I went to replace the LNB on the satellite dish located on the roof of the transmitter hut. I got the LNB replaced, and I got some signal on the air, but it wasn't very strong, and it sounded distorted. It wasn't until this past Monday, when Robin came back, that we were able to get VINA on the air properly. I ended up having to rotate the LNB almost 50° from the 0° mark on the bracket, and there was some damaged wiring that needed replaced as well.

So all in all, I'm treating my first time watching the transmitter as a lesson in proper thinking. As Robin says, you do all you can do until the job is done. If you can't do it, there's no shame in calling another engineer to assist. I'll remember that next time.

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