Friday, April 15, 2011

Narrow banding 101

Well, it's starting to happen.  As increasing numbers of 2-way users switch from wide to narrow band, the reports are coming in that my radio doesn't sound as loud as it used to and there seems to be more background noise.  The worst thing is that I can't talk as far as I used to.

We hate to tell you so, but that what we have been telling you for over half a decade.  There are two solutions to problems associated with narrow banding - You can put in more stations to compensate for deteriorating performance or you can go digital.  There are no other alternatives regardless of what you may hear from the experts.

We feel partly to blame for not providing a simple explanation of what happens when you reduce bandwidth from 25 kHz (wide band) to 12.5 kHz (narrow band).  We thought maybe an analogy might make it a little easier to understand.

Picture yourself in a basement with no windows.  Suddenly a leak develops and the basement starts to fill with water.  Think of the floor of the basement as NOISE.  The water is rising rapidly, but it's OK because you have a boat in the basement floating on the water, or NOISE.

When you reduce bandwidth, the water (NOISE) starts to rise.  The rising water (NOISE) starts to occupy more and more of the space in the basement.  You start to lose space.  Think of space as operating RANGE.  With no water on the floor, you are free to use the whole basement.  However as the water(NOISE) begins to rise, the available space (RANGE) is reduced.

As the water continues to rise, you ultimately completely run out of space (RANGE) which is what happens when you reduce bandwidth to the next proposed level of 6.25 kHz, known as Very Narrow Band (VNB). 

In our example, when water occupies too much space, YOU can no longer efficiently occupy that space.  That's what happens when you convert to narrow band.  The basement is still the same size, you are the same size, but the space available for your use is diminished.  You have more NOISE and less RANGE.

You also have another problem - reduced oxygen.  A reduction in oxygen can cause breathing problems.  Think of oxygen as AUDIO.  As the water level rises, the AUDIO (think oxygen) is reduced.  The higher the level of compression (water rising), the less oxygen (AUDIO) you have. Does that make things a little easier to understand?

In our example, a basement is a basement.  It can be a small basement or a large basement.  The result is the same.  The age, brand or model of your radio doesn't make any difference.  The effect of narrow banding is the same - Increased noise, reduced audio, and diminished range - Guaranteed!

You don't have to suffer from water in the basement.  The way to do it is start your plan for migration to digital right now BEFORE the water starts rising.  Helping you make the right decision as to how to make the transition from analog to digital is what we do.  Putting us to work is a simple as picking up the phone and calling 205.854.2611 or emailing  We've got quite a story to tell!