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Ooooh That Smell, Can’t You Smell That Smell?

Actually it smells kind of nice … but rodents find it repugnant

Engineers are prepping for winter this time of year. So are rodents.

Mice and other vermin seek warm homes to over-winter. Unmanned transmitter facilities make ideal hotels; nice warm power supplies of rack-mounted STLs, processors and remote controls are like heated mattresses or electric blankets.

Fig. 1: Mouse Magic products by Bonide are small packets permeated with peppermint and spearmint oil to repel rodents.

Keep rodents out and save the headaches of cleaning up after damage is done.

Paul Parent, who does a syndicated radio garden show, featured an interesting product to deter mice. Mouse Magic comes in a package of four pouches, the filler of which is impregnated with peppermint and spearmint oil. These smell nice to us, but mice hate them. In an enclosed area like a transmitter hut or AM antenna tuning unit, the smell is pungent but not overwhelming.

The pouches are safe for use around both children and pets. Paul has had good luck using these packets in his garden shed and garage. I stuck a few in my garage but also in the bottom of the air conditioning condenser, where I’ve found mice wintering in the past. I’ll let you know how effective the pouches are come spring.

As you place the pouches, preferably at night, shine a strong light against the door frame. Close the door and look for any light leakage to indicate potential entry points for vermin. This is easier if an assistant or fellow station employee holds the light. Run it along the entire door frame, vents and any coaxial cable entry points. Seal everything tight using foam and copper or stainless steel wool.

Remember, rodents will chew through spray foam sealer but not copper or stainless steel wool; so stuff the crack with those, then apply the foam sealer.

A little bit of preventive maintenance now will save you down time and the chore of — yuck — picking up droppings or cleaning urine-soaked equipment.

Paul Parent has been providing gardening advice for over 30 years; his program is heard nationwide.


Longtime friend of the column and consulting engineer Charles “Buc” Fitch, P.E., writes that his home town of Avon, Conn., seems to be the epicenter of a bear problem. The most recent statistics for Avon have more than 500 reported sightings in one year, of which at least 50 were violent.

Naturalists say the best defense is high-pressure sodium flood lights. Bears have enhanced night vision and they are really bothered by the orange light.

At a recent community meeting, a naturalist was asked if there was any proof or studies about this effect, and though there were several, the naturalist said, “Let’s be logical about this as well. Have you ever seen a bear hanging out or sleeping under a high-pressure sodium light?”

This phenomenon was noticed as bears preferred dumpsters under “white light.” Of course any dumpster is like a smorgasbord to a bear.

If you’ve had good luck using high-pressure sodium flood lights around your transmitter site or can offer other tips about avoiding bear problems, let me know. Email me at [email protected].


Fig. 2: The junction knob in M!ka arms is not used as the primary tensioner.

Fig. 3: Use this adjusting screw under the base for tensioning adjustments.

Fig. 4: The M!ka Briefing Book advises on proper adjustments of the mic arms.

Sleek M!ka mike arms have become popular in the United States. Here’s a tip about keeping proper tension.

U.S. Sales Manager Jeff Williams — son of former PR&E leader Jack Williams — notes that unlike some other arms you may have used, these German booms have an internal tensioning device that’s not controlled by the junction knob visible in Fig. 2. If a microphone starts to sag, pull the boom out and look underneath.

Fig. 3 shows the screwdriver tensioning bolt; turn this clockwise for more tension, counter-clockwise for less. Tightening the junction knob may help, but the proper adjustment is by this hidden tensioning bolt.

Jeff also reminds us that M!ka includes a “Briefing Book” with each arm; refer to it for more information.


Projects engineer Dan Slentz is always finding little gadgets that make an engineer’s life easier. I appreciate his sharing these “finds” with our readers.

Fig. 5: Two mini TRRS plugs to screw terminals for under 10 bucks!

His latest is a two-pack of mini TRRS (Tip-Ring-Ring-Sleeve)-to-terminal block balun that costs under $10. Shown in Fig. 5, Dan found these on CablesOnLine out of Lynbrook, N.Y..

The adaptor gives the engineer access to the mic input and stereo headphone output of many smartphones. Before you buy, note that there are some phones that use the same size mini-plug, but with five connections (TRRRS). These are all 3.5 mm plugs, sometimes referred to as 1/8-inch plugs. Just make sure you’ve got the right number of connector contacts.

Your good ideas make Workbench better (and may qualify for SBE certification credit). Send them to us at [email protected]; 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.