I hear it a lot: Where will the next generation of broadcasters come from?
Fig. 1: KXCI’s Bridgitte Thum is an instructor at the community station’s broadcasting summer school.
Fig. 2: Large eyehooks permit a vinyl-coated cable to pass through and discourage pilfering of the record library. The same idea can be used for CDs.
Well, in Tucson, Ariz., KXCI Community Broadcasting is doing its part with a broadcasting summer school. Coordinated by Bridgitte Thum, seen at the microphone in Fig. 1, and Michelle Boulet-Stephenson, the summer school teaches the fundamentals of broadcasting.
Two age groups are targeted, 9 through 12 years of age and 13 through 16. Since the station is heavy into vinyl, the kids even learn what a turntable is and how to cue up a record.
And speaking of records, Music Director Duncan Hudson included a picture of a great way to protect the LP library. Seen in Fig. 2, the large eyehooks permit a vinyl-coated cable to be passed through them and secured.
Now that satellite realignment is behind us, Bible Broadcasting Staff Engineer Steve Tuzeneu writes about a tip BBN has been using to check the performance of satellite receiving dishes.
Fig. 3: The laser holder is mounted on the inner ring of the feed horn assembly.
Fig. 4: The laser pointer fits inside. The laser should point directly to the center of the dish. If not, the feed horn mount can be adjusted.
Steve and his associates have added checks of parabola and focal length for each dish as a part of their maintenance routine.
With the dish out of shape, Steve says they have noticed the receive signal is not as high as it should be. Sometimes, this is caused by the snow cover being tighter than necessary. Other times, the dish could just be warped.
Steve and his associates measure the focal length between the center of the dish and the feed horn. When the focal length is off by just a few inches, the result is an attenuated signal.
Finally, Steve has used a portable laser, attached to the center inner ring of the feed horn, to facilitate measurement. With the laser, he can determine if the feed horn is pointed directly toward the center of the dish. At one of the sites, they gained a 50-percent improvement in received signal just by adjusting the alignment.
Keeping a dish aligned in high winds can also be a constant headache. Consider installing “guy wires” from either side of the dish to help stabilize it.
Cumulus Fresno’s Chris Basham offers a great way to keep transmitter sites organized.
Fig. 5: An inexpensive, wall-mounted transmitter site key holder. Each key is identified not only by station but also with the address.
Use a simple key holder, mounted behind the equipment racks in the locked technical operations center. As seen in Fig. 5, each transmitter site is identified, and the tag includes its address.
Sure, you may know where all the sites are located, but does your GM? Or the vacation relief engineer filling in while you’re out of town?
You can find all sorts of wall-mounted key holders on the ’net. I found one for $8 made by MMF Industries/SteelMaster and sold online by office supply store Quill (www.quill.com). It holds 10 keys and is wall-mounted.
We’ll wrap up with an interesting situation that New Hampshire Public Radio’s Steve Donnell encountered. We’ll call this an oddball outage!
A while back, Steve got an alert of a transmitter fault. The AC line voltage looked OK on the remote control, but he was only looking at one leg of the 220 V. Also puzzling: According to the remote control, the generator was not running.
Steve switched to the single-phase backup transmitter and headed for the site. When he arrived, he found that one leg of the 220 V AC feed was low, but not low enough to cause the generator to start automatically.
Steve manually started the generator and switched over to it. The main transmitter came back up without any problems. Upon arrival, Steve noticed that the generator belonging to another site tenant was running.
Fig. 6: A broken crimp/pin connecting one of the service drop cables on a pole pig transformer
When the utility company repair crew arrived, what they found can be seen in Fig. 6. The photo shows the crimp/pin that connects each one of the service drop cables to the LV (low voltage) side of the pole pig transformer. It had broken, so the building distribution panel was only seeing one leg of the 220 V feed.
The story just goes to show that utility companies have connection troubles, too!
Contribute to Workbench. You’ll help fellow engineers and qualify for SBE recertification credit. Send Workbench tips to email@example.com. Fax to (603) 472-4944.
Author John Bisset has spent 46 years in the broadcasting industry and is still learning. He handles West Coast sales for the Telos Alliance. He is SBE certified and is a past recipient of the SBE’s Educator of the Year Award.