Fig. 1: An auto-sprayer mounted inside your transmitter building helps kill flying insects. Contracting and Projects Engineer Chuck Ramold sent in a picture of an automatic sprayer he purchased for his transmitter buildings. Seen in Fig. 1, it runs on batteries and will hold a variety of spray cans. Typically you see these in restrooms, with a can of sanitizing air freshener keeping the room smelling clean.
Chuck puts a can of insect spray in the dispenser. A short spritz every half hour or so gets rid of flying insects that may find their way into the building. Chuck locates the dispenser away from the transmitter air intake, so there is no corrosion or contamination of the plated surfaces of the transmitter.
As cooler weather approaches, consider placing mothballs in the bottom of equipment racks and on the floor of the transmitter building and out buildings or enclosures, such as antenna tuning units, to keep pests away.
Fig. 2: Rodents can do great damage. Mice nearly ruined this processor. Salem Media Group’s Omaha Market Chief Jim Leedham reminds us to take precautions against mouse infestation at the transmitter site.
After acquiring a new AM, Jim did an inspection. Mice had made a nest on top of the AM’s Optimod chassis, with the resultant waste being trapped by the metal lip that runs around the top. The mess can be seen in Fig. 2. Jim removed the unit, cleaning it in the open, outdoors but still wearing a mask. There are some nasty airborne illnesses found in mouse and rat droppings. If you encounter such infestations, cover up — that means a mask, gloves and other protective wear.
Jim said the Optimod cleaned up nicely, but when he was reinstalling it, he found that one of the mice literally had hung itself on a loop of the wiring behind the rack, shown in Fig. 3.
Amazing what one can find at unmanned transmitter sites — and a good reason to do some kind of periodic inspection.
Fig. 3: This mouse died on the rack wiring. Jim went through the building with copper wool (stainless steel works too) and a can of spray foam sealant, and closed every opening he could find. The result of his hard work: No more rodents. Remember, mice can squeeze through unbelievably small crevices, so make sure you seal everything. They will chew through the foam sealer, so plug the hole or crack with the copper or stainless steel wool, and follow it with a coating of the foam.
Thunderstorm season extends into the fall. Ira Wilner, principal of Wilner Associates, which provides broadcast engineering and technical services, keeps his fingers crossed at this time of year.
Ira uses a lot of active KVM extenders between the control rooms and his automation computers, kept in a highly air-conditioned rack/server room. Even modest amounts of EMP from thunderstorms would cause the video monitors to blink; hits to the towers have destroyed a lot of KVM extenders. Ira recently replaced his plastic-cased KVM units with a brand of metal-cased extenders and also changed the Cat-5E Ethernet cables with shielded versions. So far, no more blinks.
Ira knows when the two towers in the backyard take hits, because the VSWR alarm light will latch on until he clears it. An inspection of the ball gap at the base of the tower will show more darkening, a sign of a strike that caused a moment of VSWR.
Ira’s home is on sandy soil, only a few feet above bedrock. Ira installed an electric fence that keeps his garden safe, but found that fence chargers require a decent ground if they are to be able to zap pests and keep them at bay. Driving ground rods with a sledgehammer was not only frustrating but dangerous. Even a steel rod, 5/8-inch thick and 8 feet long, will vibrate and shimmy when struck, making it a difficult target for the next blow.
Ira’s solution was to invest in a rotary hammer, a higher-performance device than a basic hammer/drill. It has a lot more torque or impact power than a drill that also hammers. They are available for rent at some big box stores, but Ira chose to buy his online. He settled on a refurbished unit, the Bosch Bulldog Extreme Max RH228VC. You also have to buy a matching ground rod adapter with the correct shank for your hammer/drill. That alone can set you back 25 percent of the cost of the drill; but if used correctly, it’ll be almost like drilling through butter. If you truly have shallow soil, the rod will stop when it hits bedrock. Attempting to sink it further is a fool’s errand. You’ll only succeed in “mushrooming” the rod and overheating the drill. Even if you could drive it into bedrock, what’s the point? That portion of the rod will not be in contact with moist soil.
Ira’s soil is so shallow he has to drive the rods at more like a 25-degree angle to get it all buried. While not deep enough to hit really wet soil, at least all of the rod is below the ground and in contact with soil and some moisture.
Ira inserted three rods in a circle, radiating from one point, and tied them together to make a better ground for the fence. The rotary hammer/drill made the job quick, safe and easy. You can choose from three modes: drill, hammer or both. For setting ground rods, use only the hammer mode. With the variable speed trigger on the Bosch unit, you can gently start it up and avoid control issues. As with all power tools, wear gloves, goggles and ear protection. The bit or ground rod adaptor is a Tru-Cut GRDS625 for 5/8-inch ground rods.
The advantage to purchasing a hammer drill is the variety of rotary hammer bits for drilling holes into concrete or for setting concrete anchors. You can also get bits, points and chisels for wood, tile and masonry work
Some folks, especially those who insist upon driving rods into bedrock, will inevitably mushroom the end. If you manage to do so in a big way, you may not be able to remove the driver tool from the rod. At $50, you don’t want to leave that adapter behind.
Avoid mushrooming by selecting ground rods with a chamfer around the top. That cutaway portion will provide room for deformation without much mushrooming. Additionally, lubricate the tool and the top of the rod, so if it gets tight, it’ll still slip off with some modest prying.
Fig. 4: Consider covering console tabletop cutouts with office tables. What do you do when you are updating a studio, remove a console and find a big hole where the old console sat? You may not have the budget for a whole new countertop, and you need a smooth surface upon which to set the new control surface.
This dilemma faced Wyoming Public Media’s technical staff Paul Montoya and Reid Fletcher.
They decided to purchase “office-style” conference-room folding tables. A 6-foot model is used for one studio, and a 4-foot length for a smaller production studio. After the folding legs were removed, the table surface was screwed into the console table top and the audio control surface placed on it. Shown in Fig. 4, the dimensions were nearly perfect. Problem solved, and without exceeding the budget. Neat idea, Paul and Reid.
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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 a past recipient of the SBE’s Educator of the Year Award.