Hey, let's just use this cable!

So I get a call from the tower today.. local backup radio doesn't seem to be working. I was in the middle of working on a light sport aircraft (I have rather mixed feelings about those things) and had to head to the tower toward the end of the day. So I head for the equipment room and check the stack. All four radios are on (good start.. so much for the "just turn the stupid thing back on" fix). Test transmissions from the controller - nothing. Test transmission from me - nothing. Tried the hand mic, controller can hear me but airplanes can't. Okay.. time to grab the spare. I can switch in the spare in about 5 minutes, so I plug it in, fire it up and we try it again. Controller can hear me, I can hear him but airplanes can't hear the transmitter at all. Hmm...

I knew there was some sort of work done on the tower recently because there's a new electronic access pad at the door. I'm running out of time in the workday, I have to pick up my daughter from drama and so I would have to come back and dig into this after dinner. My family and I have dinner and then I head back to the shop to grab a couple of things, then it's back to the tower. My working theory was that the guys installing the new security system may have co-opted one of the com cables to use for their RF link. Well, I pull the panels in the cab and look for the four RF com cables. Well whaddya know? Local backup cable is disconnected and the lead going to the antenna is nowhere to be found, at first anyway.

Then I noticed something odd... a RG-214 that looks an awful lot like my missing antenna cable connected to the localizer monitor receiver. Okay then.. this explains things. It wasn't the guys installing the security system that disconnected the radio - it was the FAA maintenance people. Oops! I should be able to have a little fun with that one. What I don't have any way of knowing is how long it's been like that. The secondary local com can't possibly work like this. For all I know, the tower's been using the main radio for awhile and just never noticed that the backup wasn't functioning. Anyway, it puts me in a bit of a pickle. I need that antenna but I can't just disconnect it from the monitor receiver. I need to call FAA sysops tomorrow and get their okay to move my antenna back where it belongs. By rights I should just be able to do that but I don't mess with any FAA stuff without their explicit permission and guidance. Their monitor should just be able to use a simple rubber duck antenna coming out the back of the unit. That's going to be my suggestion.

We'll see what happens. In the meantime, I have to fix the #2 radio now because transmitting into no antenna probably fried the relay.

Jim K.