no electronics, no idea

I'll be running the Erie and Trent Severn this summer. I have no electronics now. I was thinking about the Garmin GPS MAP 741 Coastal-plotter or the Garmin echomap 73D. My question, will either unit have built in maps for the above areas or will I need to buy separate chips??

Should I but one with a sounder? or just a chart plotter?? Now I have a factory simple sounder on board.

Many thanks...

Greetings,
Mr. CF. Best to call Garmin to confirm what coverage is "built in" and if a chip is necessary for your trip. I know nothing about chip additions as we've always cruised in areas with the information "built in" on our Garmin units. You might ask if a chip will enhance the unit by providing greater detail/more features perhaps.
Sounder? Yes, can never have too many. The actual canal part of the TSW is well marked and you will most probably have no problems if you stay in the channels BUT once you venture out onto Georgian Bay, there are lots of "gotchas" and "oopsies" where a sounder will pay for itself many $$ over. I don't think the "S" option on Garmin products adds too much to the cost.

Just so you know, much of the Erie and Champlain canals aren't well charted. I can't speak about the Trent Severn, but frankly, you don't really need a chartplotter on a canal anyway, unless you want to experience the "fun" of having your chartplotter showing you steaming along over dry land.

As for "built in" chart data, it's already obsolete when you buy the plotter. For those places where you actually need a chart, you'll want current data. You'll need to buy that, unless you run a laptop, tablet or smart phone app that allows you to use the (free) downloadable NOAA charts.

Finally, if you already have a built-in sounder, that should work fine. If you want a fish finder with a more detailed display, or forward-looking sonar, then go for it. Or if you want a 2nd sounder for redundancy. But if you're only going to display a number on the chart screen anyway, you might as well keep what you've got.

I'd also look into whether your existing transducer can send data to a new plotter. I have a 2nd legacy transducer and was wondering this myself. They all seem to be made by Airmar anyway.

We came throught the Erie Canal and TSW last spring. We have Raymarine electronics. They came with Navionics charts. We also had a backup system on our laptop. Never used the laptop for navigation. We found the Navionics to be very good with a couple of small errors.

I guess that if you have a tablet you can get navionics app for something like 50$ and the app is for me really amazing and far enough for inland waterways. Their latest feature for autorouting is really great.
I would disgress from CaptTom in the sense that I would not get on Rideau or Trent Severn without a chartplotter as you will need to cross some quite huge lakes and it will be nice to explore them and there your chartplotter will be helpful. Moreover by law you need to have maps onboard, either paper or electronic but you need them.

Garmin has proprietary Charts they produce. Most of North America comes pre loaded with the basic charts of all but the low end units. They have an upgrade to add satellite pictures and other guide book type features. Many models support wifi and an I pad or I phone can be used as a remote MFD. I would not cruise the Great Lakes with out sonar, radar and a plotter. Bent props and hull damage costs more. The GL can be very tricky. Especially up north!

All you will need is the chart and an eyeball..

Hard to get very lost in a river or dug canal.

Years ago on the Erie, I noticed our chartplotter showed us steaming along dry land.

Last summer on the Champlain I checked again. This time with brand-new charts in the 3-year-old Garmin chartplotter, as well as a couple of cell phone apps with updated charts and an old, 2000-era backup chartplotter with slightly older charts from a different source.

Yup, they all still show us steaming along dry land in spots:


Again, I'm only talking about the Erie Canal and Mohawk River, and the Champlain Canal and Champlain Narrows. I can't speak to other destinations, and certainly agree that if you get out into a lake, good, current electronic charts are almost essential.

I just don't believe they're much help in a canal or narrow, well-marked river.