When you're shopping for used marine navigation gear, the hardest call is often between a unit that's ready to use and one that needs work. That's exactly the choice here: a Navionics GPS Signal Simulator Ver 3.0 listed at $299, and a Garmin GPSMAP 740s Chartplotter at $150. One is a working simulator with a warranty; the other powers on but has sun damage to the screen and is sold for parts. Which one deserves your money depends on whether you need a functional navigation tool or a parts source for an existing Garmin setup.
Quick Verdict
If you need something that works out of the box for marine navigation testing or training, the Navionics GPS Signal Simulator Ver 3.0 is the obvious pick. It's listed as used but in perfect working condition, comes with a 90-day warranty, and ships from Spain. If you're specifically looking for a Garmin GPSMAP 740s housing, screen, or internal components-or you want a project unit that turns on but has a damaged screen-the Garmin is the lower-priced route.
Price and Condition Comparison
| Product | Listed Price | Condition | Warranty | Origin |
|---|---|---|---|---|
| Navionics GPS Signal Simulator Ver 3.0 | $299.00 | Used | 90 Day | Spain |
| Garmin GPSMAP 740s Chartplotter | $150.00 | For parts or not working | No Warranty | United States |
The Navionics costs about $150 more, but it's listed as fully functional and backed by a warranty. The Garmin is less than half the price, but you're buying it knowing the screen has sun damage and the power cable is cut.
Where Each Product Wins
The Navionics wins for anyone who needs a reliable GPS signal simulator for chartplotter testing, training, or bench work. The 90-day warranty is a real safety net, and the working condition means you can use it immediately without repairs.
The Garmin wins for cost-conscious shoppers who are willing to tinker or who specifically need Garmin GPSMAP 740s parts. The price is the lowest in this comparison, and the unit does turn on, so some components may still be usable-but the screen issue means it's not ready for navigation duty.
Product Notes
Navionics GPS Signal Simulator Ver 3.0
The Navionics GPS Signal Simulator Ver 3.0 is the safer buy if you need a functioning marine navigation simulator. It's described as in perfect working condition, and the 90-day warranty adds peace of mind that you won't be stuck with a dead unit. This is a dedicated simulator, so it's suited for testing chartplotter functions, learning navigation procedures, or running practice scenarios. Its main limitation is that it's not a full chartplotter-it's a signal simulator, not a display unit, and the $299 price is notably higher than the Garmin in this comparison. You're paying for working condition and warranty coverage, which makes sense if reliability matters more than saving money. If your goal is a ready-to-run navigation tool, this is the one to choose.
Garmin GPSMAP 740s Chartplotter
The Garmin GPSMAP 740s is a familiar marine chartplotter name, but this specific unit is sold for parts or not working. The description says it turns on and functions, but has screen damage from the sun, and the power cable is cut. It comes with a sun cover, and the listing notes a custom bundle. The low $150 price makes it an attractive buy if you need Garmin parts or want to attempt a repair, but there's no warranty, so you're absorbing the risk. The screen damage is a clear limitation: even though the unit powers up, you can't rely on it for navigation as-is. If you already own a Garmin GPSMAP 740s with a good screen and need internal parts, or if you want a project unit, this could be worth the gamble. For immediate navigation use, it falls short.
Final Choice by Use Case
Choose the Navionics GPS Signal Simulator Ver 3.0 if you want a working marine navigation simulator with warranty support for testing or training. It's the dependable choice for someone who needs a functional tool right away.
Choose the Garmin GPSMAP 740s if you're on a tight budget and either need Garmin-specific parts or you're prepared to deal with a sun-damaged screen. It's the better fit for a repair project or a parts donor, not for reliable on-water navigation.
If you're still unsure, ask yourself: are you buying something to use, or something to fix? That answer points you to the right listing.
