Testing the Pearce Simpson Gladding Islander RDF

The top secret Parmain laboratories don't often do product reviews, but when the opportunity presented itself to evaluate the Pearce Simpson Gladding Islander position calculating  system, we just couldn't resist. We have to hand it to their clever designers, and marketing staff for creating this unique combination of a navigation system coupled with a shipboard audio entertainment system, all in one elegant compact package.

Our technician's (Peter Scharff shown above) ran this versatile system through its paces in both our laboratory, and aboard one of our test vessels in real world conditions. We evaluated it's position calculating capabilities, ease of use, and durability.

One of the things we were most impressed with was this units portability. Unlike some units we have tested, the built in leatherette handle makes taking it home, or to the beach a snap.

The Gladding Islander is packed with features including a dial light for night time use, and a broad range of frequencies that allows for both position locating, and listening fun. Imagine sitting on your yacht, and listening to the local airport's radio traffic, or hearing the weather forecast on the VHF channel. The great sensitivity of this receiver comes from the use of many solid state transistors in place of less reliable integrated circuits. 

Despite the fun that comes from listening to exotic radio stations, this unit can actually tell you where you are. The Islander has two antennas. One is general purpose antenna, and the other is a sensitive rotating ferrite antenna.

The process is simple. Pick an AM station with a known latitude and longitude position. Tune the station so the meter shows the highest strength. Now throw the DF switch on, and rotate the ferrite antenna until the meter shows the lowest signal. Rotate the compass card under the antenna to match your ship's compass, read the bearing. Draw this line on your chart. Pick a second AM station, and repeat. Where the lines cross, is where you are.

We tested a variety of AM local stations with terriffic results. The accuracy was an astounding, +- 1 to 2 miles, even while bouncing around in the bay.

On the whole, with an original purchase price of $139.95, and it can be less expensive online, the Pearce Simpson Gladding Islander represents an excellent buy for the boater who wants an inexpensive position locating capability, with the bonus of getting an entertainment system at the same time. With its chic leatherette finish and brushed aluminum face plate the Islander will add stylish touch to any yachts interior. We do however wish the manufacturer had included a CD with all of the coastal AM station antenna lat/long positions, although you can find them on line.

From the navigators viewpoint, a chart with a compass was better than not having either. When the clock, and sextant was added, navigation became even more precise. The RDF and LORAN were huge improvements that allowed more accurate navigation in poor weather. The modern WAAS enabled GPS chartplotters are now accurate to about 10 feet. The question is as always. When your fifty cent fuse blows, and shuts down your Chartomatic 2000, can you find out where you are, at all?

Here is a nice collection of RDF units old, and older.

Author's footnote: The last marine band non directional beacons were decommissioned in 2000, but AM stations work fine, mostly. LORAN joined the Museum of Shattered Dreams on February 8th 2010.