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Cheaper Is Not Always Better

Also, shine a light on the subject, hands-free

Fig. 1: It’s not over ’til the fat PSU “sings.” Cheaply-built PC power supplies can be a source of mystery mechanical noise. Those specially priced $29 OEM computer power supplies you see in online ads can be tempting when you need a stockpile of PSUs for a fast repair. But it’s worth it to spring for a few of the pricier ones for a number of reasons.

Alan Peterson, engineer at the Radio America Network in Arlington, Va., and a frequent Workbench contributor, had a production studio computer that developed an odd mechanical whine around 8 kHz. Turning off each fan, one at a time, and disconnecting the disk drive did nothing to isolate the problem.

The problem turned out to be a “singing” component on the circuit board inside the power supply. Swapping out the PSU for a better-built one did the trick, and the whine disappeared.

Alan concludes that surprises like this keep the job from getting old.


Greg Muir, principal of Wolfram Engineering, offers a tip for those of us needing to shine a little more light on the subject.

Purported to be the brightest headlamp available, the Boruit 3x CREE XM-L T6 8000 Lumens LED Headlamp Head Light features three LED lights mounted on a headband. Used as a bicycle headlamp, the lights can be individually controlled and include a charger for the rear-mounted battery pack.

No longer will you have to strain your eyes troubleshooting under the console cabinetry or in some recessed corner of the transmitter — holding a trouble lamp in one hand and tools or a meter in the other. The headlamp mounting frame is adjustable, and it costs less than $20.

Find it at


The Federal Emergency Management Agency has released an interesting link that permits visualization of natural disaster history for both states and counties. All types of natural disasters are tabulated.

Interested in the flooding history of your transmitter — or studio — site? Here’s the link:


Platinum Tools of Newbury Park, Calif., launched the Fault Trapper Smart Tester, which ends guessing about circuit breaker tripping issues.

Fig. 2: The Fault Trapper detects and identifies a variety of electrical faults. Not only will this device detect the type of fault, it will timestamp when the fault happens and locate the position of an electrical “event” that caused intermittent/persistent circuit breaker trips and No Fault Found conditions in either feet or meters.

The Fault Trapper (part number TFT100) monitors live circuits to detect faults when traditional methods fail to find them. The device runs on the power from the circuit until the circuit breaker trips. Then it captures the time and distance to opens, shorts or arc faults, saving the event information in memory for later investigation. The last faults can be viewed off-line using battery power.

The Fault Trapper is unique, as it can detect faults that trip and don’t trip circuit breakers. If the circuit breaker trips the backup battery powers the Fault Trapper to allow for an orderly shutdown. The last faults can be viewed using the battery power. The Fault Trapper tester allows for unattended monitoring of dedicated circuits for NFF conditions. Just set it up, press the Start button to begin monitoring and walk away. Come back later or the next day to find out the why-when-and-where of circuit breaker trips and NFF conditions.

 This Smart Tester should be suitable for monitoring transmitter breaker trips at remote sites, as it identifies opens, shorts and arc faults. Visit for more information.

You have good ideas, we’re looking for good ideas. Send Workbench tips to [email protected]. Fax to (603) 472-4944. Bonus: Tips qualify for SBE recertification credit.

Author John Bisset has spent 46 years in the broadcasting industry. 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.