Eagle and Lowrance Transducer Selection Guide
To select the transducer that's best suited to your needs, you
need to consider the transducer's operating frequency, cone angle,
and type of installation.
Frequency
Most of the sonar units that we sell
accessories for operate at 192 or 200 kHz (kilohertz). Some models use 50 kHz. A
few are dual frequency capable, meaning they can use both 50 and 200 kHz
transducers. Typically, high frequency (192 or 200 kHz) sonar units provide the
best resolution and definition of structure and targets. They excel at showing
minute details of the underwater world. 50 kHz units have much greater depth
penetration capability, but show less definition. 50 kHz transducers also
usually have a much wider cone angle than 192 or 200 kHz
transducers.
You must match the transducer's frequency
to the sonar unit. For example, a 192 kHz sonar unit requires a 192 kHz
transducer.
Cone
Angle
A transducer's cone angle determines its
coverage area of the underwater world. The wider the cone angle, the greater the
area that's covered. We offer a variety of 192 kHz transducers with either a
wide (20°) or narrow (8°) cone angle. We also offer a variety of 200 kHz
transducers with either a wide (20°) or narrow (12°) cone angle. The 50 kHz
transducers come with a 35° cone angle. And the dual frequency transducers come
with both a narrow (12°) 200 kHz and a 50 kHz cone angles.
Generally, use a wide cone angle for
fishing shallow to medium depths. The narrow cone penetrates to deeper depths,
but shows less fish and structure due to its narrow beam.
The depth capability of your sonar units
depends on its transmitter power, receiver, sensitivity, frequency, transducer
and transducer installation. Other things that effect depth capability are:
water conditions and type, (all sonars will show deeper depth readings in fresh
water than salt) and bottom conditions.
Types of Transducer
Installation
Most of our
permanent-mount transducers are designed for high-speed operations. For the best
results, the transducer should be placed where a smooth, undisturbed flow of
water will pass across the face of the transducer at all boat speeds. Read
your transducer's owner's manual before installing the
transducer!
Transom
Mount
The transom-mount transducer is the most popular, and it's
generally the easiest to install. The Skimmer® transducer design performs best
when it is slightly below the boat's hull. A plastic transducer is recommended
on aluminum or steel-hulled boats to avoid potential electrolysis
problems.
Mounting the transducer on the transom is recommended for
outboard and stern-drive (I/O) powered boats only. Transom mounting is ideal for
high-speed operation and models with the "kick-up" feature will prevent damage
if the transducer strikes an object.
Make certain that the chosen
location doesn't interfere with the boat's trailer. DO NOT mount the transducer
directly behind the ribs, or thru-hull fittings. Typically, on aluminum boats,
mounting the transducer between two ribs works best. On all hulls, mount the
transducer at least one foot away from the engine's lower unit. This helps to
prevent air bubbles from the transducer interfering with the
propeller.
Periodically wash the bottom of the transducer with soap and
water to remove any oil film or growth that may collect. Oil and dirt reduce the
transducer's sensitivity and can even prevent its
operation.
Shoot-Thru-Hull
Mount
In this
installation, the transducer is bonded to the inside of the hull with epoxy.
Ideally, the transducer is placed in the aft third of the hull close to the
centerline. The signal "shoots through" the hull with some loss of signal
strength. This installation must be made in an area of the hull that is made
from solid fiberglass, with no air bubbles or separated layers. If the hull is
of multi-layer or "sandwich" construction, you will have to remove the inner
layer of fiberglass and the wood or foam core to expose the outer layer of the
hull. This type of mount is recommended only with 192 or 200 kHz
transducers.
Bolt-Thru-Hull
Mount
In this type of
installation, a hole is cut in the hull and the transducer is mounted through
the hull by means of a threaded shaft and nut. If the boat hull has a dead rise
higher than 10 degrees, fairing blocks made from wood or plastic must be
fabricated so that the transducer will mount in a completely vertical position.
The TH-FLW P5 model does not require a fairing block.
On in-boards, the
transducer must be installed ahead of the propeller, shaft(s), and engine water
intake(s).
If the boat's hull is made of steel or aluminum, use a plastic
transducer to prevent electrolysis problems.
Trolling Motor
Mount
The PD-W "pod"
transducer is designed for mounting on an electric trolling motor. It has two
slots for a hose clamp (which must be purchased separately). Skimmer®
transducers can also be mounted on a trolling motor using the TMB-S trolling
motor bracket. It's curved to fit the contour of most electric trolling
motors.
