6 Best Lowrance External Gps Antennas For Signal Strength To Go Anywhere

You’re navigating a tricky channel, keeping one eye on the depth finder and the other on the chartplotter, when your screen suddenly freezes. The little boat icon stops moving, and a "No GPS Fix" warning flashes. In that moment, the convenience of modern electronics vanishes, and you’re left relying on old-school seamanship—a situation an external antenna is designed to prevent. Upgrading your GPS antenna isn’t just about getting a faster signal; it’s about building a reliable navigation system that works when you need it most.

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Why Your Lowrance Unit Needs an External Antenna

The GPS receiver built into your Lowrance head unit is surprisingly capable, but it lives in a tough neighborhood. It’s tucked inside a console, surrounded by other electronics that can create signal interference. More importantly, it’s often located under a T-top, hardtop, or even the roof of a pilothouse, which physically blocks its view of the sky.

Think of it like trying to get a cell signal in a basement. You might get one or two bars, but it’s weak and unreliable. A GPS antenna works the same way; it needs a clear, unobstructed line of sight to the satellites orbiting overhead. An external antenna moves that receiver from the "basement" of your console to the "rooftop," giving it the best possible view.

This simple move solves the two biggest problems: physical obstruction and electronic interference. The result is a faster, more stable, and more accurate position lock. For anyone who fishes offshore, navigates in fog, or simply demands that their gear works every time, an external antenna isn’t a luxury—it’s a foundational part of a serious marine electronics setup.

Lowrance Point-1: Top GPS and Heading Sensor

The Point-1 is the go-to external antenna for most Lowrance users, and for good reason. It’s not just a GPS antenna; it’s also an integrated heading sensor. This is a crucial distinction. Your standard GPS can tell you your Course Over Ground (COG), which is the direction your boat is moving. A heading sensor tells you the direction the bow is pointing, even when you’re stationary.

Why does that matter? Imagine you’re drifting over a wreck, trying to stay on top of the structure. With only COG, your map will swing around wildly as the current pushes you. With a heading sensor, the map orientation stays locked to the direction your boat is facing, making it infinitely easier to understand your position relative to your target.

This heading data is also essential for advanced features like radar overlay. It allows your chartplotter to accurately align the radar image with your navigation chart, giving you a single, comprehensive view of your surroundings. With a 10 Hz update rate, the Point-1 delivers smooth, real-time cursor movement on your screen, eliminating that frustrating lag you get with slower receivers. For the vast majority of boaters, the Point-1 is the perfect blend of performance and value.

Lowrance LGC-16W: A Reliable NMEA 2000 Puck

Not everyone needs the advanced features of a heading sensor. Sometimes, you just need a rock-solid GPS signal from a simple, reliable device. That’s where the LGC-16W comes in. This is a straightforward GPS "puck" that does one job and does it exceptionally well: it acquires and holds a strong satellite lock.

This antenna is the perfect solution for boaters who have a clear need for an external receiver but don’t require radar overlay or precise heading data for slow-speed fishing. If your primary goal is to overcome a blocked internal antenna on an older HDS unit or a simple Elite FS, the LGC-16W is a cost-effective and robust choice. It plugs directly into your NMEA 2000 network and just works.

Think of it as the workhorse of the GPS world. It’s a 5 Hz receiver, which is plenty fast for general navigation, and it provides the accuracy and reliability you expect from a dedicated external unit. If your chartplotter is struggling to maintain a fix and you just want to solve that problem without breaking the bank, the LGC-16W is your answer.

Lowrance GPS 24i XD for High-Accuracy Needs

For the tournament angler or the serious navigator who demands the absolute best, the GPS 24i XD takes accuracy to another level. The "XD" stands for eXtreme Detail, and it delivers on that promise by communicating with multiple satellite constellations simultaneously, including GPS, GLONASS, and Galileo. This multi-constellation support means it can see more satellites at once, resulting in a faster initial fix and an incredibly stable signal, even in challenging locations like near tall bluffs or in deep canyons.

The real standout feature is its 20 Hz update rate. That’s 20 position updates every second, twice as fast as the already-quick Point-1. On your screen, this translates to an exceptionally smooth and fluid boat icon that tracks your every move with zero perceptible lag. When you’re trying to pinpoint a tiny piece of underwater structure or navigate a crowded harbor, that level of responsiveness makes a real difference.

The GPS 24i XD is an investment in precision. It doesn’t include a heading sensor like the Point-1, so its focus is purely on providing the most accurate and responsive position data possible. It’s the choice for professionals and enthusiasts who need to know their exact spot on the water, right now.

Lowrance Precision-9 for Advanced Navigation

It’s important to understand that the Precision-9 is not a GPS antenna. Instead, it’s a dedicated heading and rate-of-turn sensor that serves as the brain for advanced navigation and autopilot systems. So why is it on this list? Because it’s the component that unlocks the full potential of your GPS data, making it an essential part of a high-performance setup.

The Precision-9 uses a sophisticated solid-state sensor array to output highly accurate heading, rate of turn, pitch, and roll information to your NMEA 2000 network. While a Point-1 provides basic heading, the Precision-9 provides it with unparalleled accuracy and stability, which is critical for autopilot performance. It’s the difference between an autopilot that smoothly holds a course and one that constantly "hunts" back and forth.

If you are building a system with a Lowrance Outboard Pilot or a more complex autopilot, the Precision-9 is non-negotiable. It provides the core data that allows the system to make smart, subtle steering adjustments. It transforms your GPS from a simple positioning tool into a key component of a fully integrated vessel control system.

Simrad GS25: A Versatile Lowrance Alternative

Because Lowrance, Simrad, and B&G all operate under the Navico parent company, their NMEA 2000 devices are often interchangeable. The Simrad GS25 is a perfect example. Functionally, it is a direct equivalent to the Lowrance Point-1, offering both a high-speed 10 Hz GPS receiver and an integrated heading sensor in a single, compact unit.

This cross-compatibility gives you options. Sometimes, the Simrad-branded GS25 might be more readily available or offered at a better price than the Point-1. There is no performance penalty for "mixing" brands in this case; once connected to your NMEA 2000 network, your Lowrance display will recognize and use the GS25 just as it would its own branded antenna.

The GS25 is a proven performer, trusted in both recreational and light commercial applications. It provides the same benefits as the Point-1: stable chart orientation, accurate radar overlay, and smooth on-screen tracking. If you’re in the market for a combination GPS/heading sensor, it’s always worth checking the price and availability of both the Point-1 and the GS25.

Lowrance Outboard Pilot: Integrated Autopilot GPS

The Lowrance Outboard Pilot isn’t just an antenna; it’s a complete autopilot system that relies on a high-quality external GPS antenna to function. Most Outboard Pilot kits come bundled with a Point-1 antenna for this very reason. The antenna is the "eyes" of the system, providing the precise position and heading data the autopilot computer (NAC-1) needs to do its job.

In this context, the antenna’s role expands beyond simple navigation. It feeds a constant stream of data that allows the autopilot to execute complex commands. When you tell it to navigate to a waypoint or follow a pre-planned route, the autopilot is constantly comparing the boat’s actual position and heading (from the Point-1) to the desired track and making micro-adjustments to the steering.

The quality of the antenna directly impacts the performance of the autopilot. A stable, accurate signal from a well-mounted Point-1 allows the system to hold a laser-straight course, even in crosswinds or currents. This integration highlights how an external antenna can become the cornerstone of a much more capable and automated navigation system.

Mounting Your Antenna for the Strongest Signal

Where you mount your external antenna is just as important as which one you choose. The single most important rule is to give it a clear, 360-degree view of the sky. Any obstruction can degrade the signal and defeat the purpose of the upgrade.

Here are the best mounting locations, in order of preference:

• On top of a T-Top or Hardtop: This is the ideal spot. It’s the highest point on the boat, free from obstructions and electronic interference.
• On a Pole Mount: If you don’t have a hardtop, a dedicated pole mount on the stern or arch can elevate the antenna above everything else.
• On the Gunwale or Rail: This is a workable option, but be mindful that people, canvas, or fishing rods can temporarily block the signal.

When installing, pay close attention to two things. First, any antenna with a heading sensor (like the Point-1 or GS25) has a small arrow on the casing. This arrow must be pointed directly toward the bow of the boat and be parallel to the keel. If it’s misaligned, all of your heading information will be incorrect. Second, keep the antenna at least three feet away from other antennas (especially VHF and radar) and large metal objects to prevent signal interference.

Choosing the right external GPS antenna is about matching the hardware to your mission on the water. Whether you need a simple signal boost with an LGC-16W or are building a fully integrated autopilot system around a Point-1 and Precision-9, the goal is the same: to create a navigation system that is reliable, accurate, and gives you the confidence to go anywhere. A solid GPS signal is the foundation upon which all modern marine electronics are built.