LED lighting is really hitting its stride. Look
at the assortment of flashlights now available. Most of us can remember when
portable lighting meant an Eveready flashlight with two D cells to light the
Fig. 1: A closeup of the LED strip, with built-in
Sunbury Broadcasting’s Chief
Engineer Harry Bingaman was doing a project that required some under-counter lighting.
Harry made a trip to the local electrical distributor to see what was
available. Companies now make LED strip lighting that runs on 12 VDC, and can
be purchased in different lengths. You even have a choice of bright white or
warm white. Interconnecting cable harnesses and Y-adapters to do the branching
of the strips are available, too.
It was exactly what Harry was
looking for, until he totaled the price. Yikes. Time for a Plan B!
On the Internet, Harry found CitiPower. See citipower.co,
and once there, click on CitiPower LED Product. Or do an eBay search under LED
You’ll find more choices that you can imagine. These
strips can be ordered as waterproof or non-waterproof, depending on your
application. They run on 12 VDC and have a 3M self-adhesive strip on the back
of them for easy mounting to any surface. They can be cut every three LEDs, and
every cut-point has a copper donut pad to solder your power connections as seen
in Fig. 1. They come in almost every conceivable color.
Harry ordered a roll of
waterproof and non-waterproof in bright white. The rolls contain 300 LEDs and
the length is 5 meters. The cost was $7.90, and they worked great, providing
tons of light. See an example in Fig. 2. Harry had to drop the voltage, because
when fully powered, the light washed out the camera!
Fig. 2: The LED light strip in action. Boy, these are
One thing Harry discovered is
that the non-waterproof version is easier to cut and solder to the pads. The waterproof
series has a clear silicone coating and needs to be peeled away to make your
connections, but this is not a horrible task.
Harry also used the LED strips to light some
areas in the transmitter rooms that were a little cramped for any type of incandescent
or fluorescent lighting. Depending on the number of LEDs in your application,
the strip can be driven by a wall-wart power supply.
In fact, your imagination is the limit when using
this type of lighting. I visited the website and agree with Harry. Take a look
at their new product, the LED net light, which is coming. Imagine fishing net
made of LEDs — ideal for a studio ceiling!
* * *
Graham Brock Inc. consultant
Stu Graham has just the ticket for ensuring a good RF connection. Pictured in Fig.
3 is a tube of silver conductive grease, manufactured by MG Chemicals (www.mgchemicals.com). You can buy this grease in
hypodermic tubes, as pictured.
Fig. 3: Silver conductive grease, a great RF lubricant.
| Fig. 4:Improve bullet conductivity using MG Chemicals’ silver grease.|
This silver grease provides
both antistatic conductivity and maximum thermal conductivity between sliding
surfaces, while providing protection from moisture and corrosion. Typical
applications include lubrication of rotary coils in AM phasors and tuning
units. The grease can also be applied to the moving slider assemblies in older
FM transmitter tuning and loading controls, or applied to RF bullets, as seen
in Fig. 4.
The grease is available from Allied and Mouser, and runs about
$20 per syringe. It’s not cheap, but preventive maintenance using this grease
is cheap insurance.
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Author John Bisset has spent 43 years in the broadcasting industry and
is still learning. He is SBE certified and is a past recipient of the SBE’s
Educator of the Year Award.