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Freshen Your Mics With Li.LAC

Its UV-C chamber disinfects three handheld mics or wireless transmitters

Managers of radio stations, houses of worship, universities and corporate and government meeting rooms all face the question, “How can we effectively disinfect our microphones after an event?”

iSEMcon, which is in the “front of house” business, recently introduced the Li.LAC Microphone Disinfector. It uses controlled exposure to ultraviolet light (UV-C) to kill over 99% of bacteria and viruses on microphone surfaces, metal grilles and the windscreens underneath. 

It’s a rugged product, designed by live event touring professionals and mounted in a 19-inch, 3RU rackmount format. Load up to three microphones or several lavalier or headset microphones, headsets or belt packs, close the drawer, and press “Start.” Disinfection takes 12 minutes or less.

The Li.LAC Microphone Disinfector is available online. It lists for $1,599. The company is based in Germany and has an office in Ohio; general info can be found here

The company notes that the simple operation of this device speeds a job that’s critical in today’s environment. We’re not completely out of the woods with respect to COVID-19; and even when we get there, microphone hygiene will remain important. 

The Li.LAC Microphone Disinfector uses UV-C light to disinfect the mics.

Many arms, light work

In the Feb. 15 Workbench, we discussed a useful circuit called an Octopus. Its purpose is to analyze components while they are in a circuit. 

Longtime Workbench friend Paul Sagi first encountered the Octopus years ago in Popular Electronics magazine. At one of his first radio station jobs, he had to repair numerous switched-mode power supplies, as are found in everything from transmitters to audio processors and network gear.

The most common failure components were capacitors followed by MOSFETs, ICs and other semiconductors; Paul found that inductors almost never failed.

Removing components from a printed circuit board was a nuisance, so Paul used signal injection and an Octopus to find faulty capacitors and the rare faulty inductor.  

Paul fed a 100 kHz sine wave, 200 mV peak into the components. Those specs avoided having the semiconductor junctions respond to the test signal. By the angle of the trace on the oscilloscope, Paul could measure the equivalent series resistance of the capacitor; an ESR of less than 0.1 Ohms usually indicates a good electrolytic capacitor, as does an ellipse.

Take DAT!

Buried away in your storage closet may be a defective Digital Audio Tape machine or two. Before you toss these finicky machines, Paul passes on a document from Eddie Ciletti that describes machine repair tips for Sony and Panasonic DAT models. Find it here.

Bright ideas from Darkwood

Projects engineer Dan Slentz found a neat site that has a variety of Windows freeware, developed by Paul Marshall of Darkwood Designs using Borland Delphi. 

Offerings includes individual and multiple volume metering indicators, a dB graphical display of audio frequencies, an audio tone generator and a jpeg image cropper. 

On the company’s website, click on “More PC Software.”

[Check Out More of Workbench Here]

More free posters

Tektronix has put together a couple of interesting posters showing the fundamentals of oscilloscopes. The posters are in color and free to download. Head over to for “Anatomy of an oscilloscope” and “Basic features and functions of an oscilloscope.” 

The posters provide a good review for seasoned engineers as well as an excellent training tool for the entry-level engineer; and they will liven up your office.

Let’s go to the tape

If you work with conduit or rigid transmission line, take a look at the T1 Tomahawk Digital Tape Measure

This is the tape measure for all measurements! It has a physical tape plus an OLED measurement display; and its ROCK Measuring App allows the T1 to synchronize any measurements with your iOS or Android phone. 

The display can be zeroed from any position, regardless of the amount of conventional measuring tape extended. A special bracket will hold a pencil or a Sharpie (or similar brand) marker. There is a side-mounted “E-paper” feature that records an unlimited number of measurements — no more writing the measurements down on a piece of paper! Measurements are recorded electronically on the T1.

The Tomahawk Digital Tape Measure

The T1 Tomahawk Digital Tape Measure also includes a high-visibility green laser. 

There’s a good video about it on YouTube.

This tool is not cheap, listing for around $250, but judging from the reviews on the Reekon Tools website, the time savings and accuracy may make it a worthwhile investment. 

John Bisset, CPBE, has spent over 50 years in the broadcasting industry and is in his 33nd year writing Workbench. He handles western U.S. radio sales for the Telos Alliance and is a past recipient of the SBE’s Educator of the Year Award. Workbench submissions are encouraged and qualify for SBE recertification credit. Email [email protected].