What Did You Say? The Truth About Radios

By Ocean Eye, Inc.’s Chris Gabel

Editor’s Note: This is a continuation of the article What Did You Say? The Truth About Radios, which ran as an excerpt in the January/February issue of UNDERWATER Magazine. The excerpt can be read here

You know the old adage: the job is only as successful as its weakest link. Nowhere is that more true than whenyou are depending on your electronics to get the job done. We expect that when we turn them on that they will function as designed every time even after they’ve been ignored for long periods of time. Interrupted communications will abort a dive (unless you have the memory and desire to resort to line pull signals), and can even stop the rest of the dive day. Personally, the last thing I want tohave happen is to lose production time because of not performing some simple and quick equipment checks.

The good part and bad part about today’s electronics is that they have become significantly more reliable. We have all gotten used to devices that offer more options and require less maintenance. The flip side of that benefit is with the reliability sometimes comes complacency. The old “It worked yesterday and it will work tomorrow”attitude can come into play.

The Most Important Piece – POWER!

Yes, power. Without a supply of electricity, radios don’t work. Since most radios are powered by batteries, let’s take a look at the types of batteries you may encounter. Some radios are powered by non-rechargeable batteries, also known as single-use batteries. Many units today come with rechargeable batteries. In fact, several radio manufacturers now only offer a rechargeable battery in their pieces. You may no longer have the option of a rechargeable or a single use battery.

There are several different variations of rechargeable batteries. It seems like there is new technology being released every other day. If you don’t think so, take a look at the news. Since the introduction of things like smart phones and electric cars, the battery density, reliability, and power output changes faster and faster.

The main players are NiCad, NiMH, and Li-Ion. NiMH (Nickel MetalHydride) offer higher energy densities than NiCads (Nickel Cadmium). NiCad has about half of the capacity of NiMH batteries. That means more power from the battery withno additional weight. NiCad batteries tend to suffer from the “memory effect,” NiMH batteries do not.

Li-Ion batteries represent the current gold standard for portable power. They produce the same energy as the NiMH batteries but with a 35% weight advantage. That means the same amount of powerin a smaller footprint. The downside is increased cost to the consumer.

No matter what battery you choose or that comes delivered with your particular radio, it’s important to check and maintain them on a regular basis.

One big challenge with batteries is the environment that they have to work in. Saltwater corrodes terminals, and once that happens, it’s just a matter of time before nothing works. I’ve personally pulled out batteries that had so much corrosion they solidified in to the ring terminal. Others looked as if they spontaneously became pregnant because the casing was about to rupture. None of which was a happy clean up experience.

I found that nothing, and I mean nothing, is more frustrating than a bad ground. A bad ground can cause a myriad of frustrating symptoms that can be difficult to track down.

Most of the batteries are hidden in creative ways so that they are not visible and do not take up valuable space. That’s good news and bad news – out of sight but out of mind. You need to dig out the battery regularly and check the terminals for corrosion and clean them. Make sure that you pay attention to both terminals equally.

Just do an overall visual inspection of your battery. As I noted above, all batteries are not created equal. Some are rechargeable, some are not (sometimes called single-use batteries). Some will last longer than others and some have specific requirements. Note the battery type, model, and any other specifics that are pertinent to daily operation on the inside of the lid.

For example. on some models, you need to make sure that the charger is unplugged from the unit before use. I’m not saying you need to publish the entire manual on the box, just the really important day-to-day information. If you have multiple radios in your environment, what you use one day may not be what you use the next. It’s just going to make life easier for everyone if the operators don’t have to track down the most important information or guess.

Bad things can happen when people have to guess. Not the least of which is smoke and fire.

Keep in mind that even rechargeable batteries will degrade over time. Most rechargeable batteries get delivered in a discharged state and need to be charged before use. It’s important to condition the battery every two to three weeks. Conditioning means to fully discharge and then
charge the battery. If you don’t, it could potentially shorten the life of the battery.The exception to that rule is the Li-Ion, or Lithium Ion, battery (they don’t suffer from the memory effect). That said, there has been a recent recommendation to only discharge Lithium Ion batteries to no less than about 60%. That will allow it to achieve its maximum service life.

It’s normal for the battery to be warm to the touch during charging. If the battery isn’t going to be used for a month or longer, most manufacturers recommend that you remove the battery from the charger and store in a cool dry place.

Battery life can very but under normal conditions they should last between 500 and 800 charges. That equates to somewhere around three years. The battery will hold a charge for a shorter and shorter amount of time as its life cycle comes to an end. This is a good warning sign that it’s time to make that replacement battery purchase.

Short-term storage requires you to keep the battery clean and dry. If you’re not going to use it for a while, it becomes even more important to make sure that you keep the battery in a cool (not freezing cold) and dry place. Make sure that the space is vented. Keep them away from metal objects. I know, that may seem like common sense, but there are times folks are in a hurry, throw the battery on a shelf and end up shorting the contacts on something as silly as the shelf supports.

Also keep in mind that all three of the rechargeable batteries discussed in this article will self-discharge during storage. They don’t keep a charge on the shelf forever. Remember to break in your batteries again after long term storage before use.

Check with the particular manufacturer ofyour batteries for specific care instructions.

One thing to remember is that a low batteryor a battery at the end of its life cycle can produce strange symptoms on your radio – squealing feedback, interrupted communications, and other problems. A radio that has worked faithfully for years may suddenly start doing the strangest things. So you may not have to replace entire radio.

When in doubt, the first thing to do is replace your battery.

Cleanliness is next to, well, you know. If there is one commonality that I’ve seen in the radios that I’ve used and/or worked on, is that cleaning is not the first priority. That’s especially true in the areas that you don’t necessarily see every day.

Some of the things that get trapped under the cover plate would curl your hair. Most are benign – bugs, dirt, and other biological matter get under the plate and build up. Every once in a while, you need to pull the plate and give the entire radio a good cleaning. If you’re not comfortable pulling the plateoff, have a trained technician do it.

While it’s apart, take a look at the components. You don’t have to bean electronic genius to look over the switches, speakers, and potentiometers and see if they are rusted or damaged. Again, if you’re not comfortable with removing the cover, then by all means, don’t. Have a qualified technician look over the radio and let you know what they find. Don’t be afraid to ask them to explain and show you their findings including sending you photos of the problem components.

Rigging the radio – just one word of advice, don’t. If it’s broke, fix it. If you need to fix it, fix it with the right component. I know that it’s a temptation to use whatever you have on-site to get you through the day,but it may end up costing you more in the end. With more sophisticated parts that are being utilized in today’s radios, you can end up damaging the radio permanently by using bailing wire and duct tape to get through a couple of hours.

Check the seal. Take a look at all of the seals. Not only the lid seal,but also check the seals on the faceplate and around the pressure relief valve (if equipped). Just like any other seal, make sure that they areproperly cleaned and lubricated. Check for cracks and breaks in the rubber. If in doubt, replace it.

You need to take care of your radios as you would any other piece of dive gear. Just because it doesn’t deliver air doesn’t mean that it’s any less important. They all need to be checked at least annually. You know that if you don’t, that radio will fail at the most inopportune time.

Dive safe.

Have a comment or question on equipment maintenance for Chris Gabel? You can reach him at cgabel@oceaneyeinc.com.