When I first started sailing, I used paper charts and only a compass to navigate. GPS was too expensive at the time. Now I use a Raymarine chart-plotter with multiple backups on a tablet and PC. I only use charts in digital format because they are updated more frequently and less expensive (free) from NOAA. Both RNC (raster navigational charts) and ENC (electronic navigational charts) can be downloaded from NOAA's website at no charge. Since I have become more dependent on the digital version, I make it a point to have charts available on a backup PC. Both the onboard and laptop computers have solid state drives installed for durability.
I am currently using Rosepoint's New Coastal Explorer for trip planning, backup and reference while underway. It uses free NOAA raster charts and vector charts which are frequently updated whenever I have an internet connection.
At the helm I use a Raymarine A65 chart-plotter and an Axiom 7 multi-function display. The Axiom uses Navionics charts.
Sonar charts provide more detail from crowd sourced data which is especially useful when off the beaten path in an anchorage where the water has not been surveyed in a while.
I use a Garmin handheld for backup and as an anchor alarm permanently mounted in the cabin. I also have a USB GPS plugged into a PC which runs Coastal Explorer. My current plans are to link to this PC with a waterproof Tablet using Remote PC. In the unlikely event the entire GPS system would go down I could use a hand bearing compass and charts viewed on a PC or tablet.
Local Notice to Mariners
Before starting a cruise a good way to get up to speed on the area is to download the latest local notice to mariners from the USCG District 7 website or USCG District 8 depending on the area. This site will keep you up to date on any hazards, construction, changes, etc. Any late breaking news can be heard while monitoring channel 16 on your marine radio. The USCG will usually break in a couple of times a day and tell you to switch to channel 22 for the latest local notice to mariners. US Coast Guard Nav Center website.
US Coast Guard Nav Center backup site to be used when the main site is down for maintenance or some other reason.
I use Coastal Explorer for Tide and Current but the following tidal and current tables are available from NOAA:
Tidal Current Predictions.
Also pick a tide station from a map:
Other Navigational Links
Navionics Sonar Charts's Data uploaded from other boaters is compiled and displayed by various Navionics products. It can also be viewed on their web app.
Google Earth's satellite pictures aren't always up to date but they are sometimes more current than NOAA charts in some areas, especially after a storm. Charts are more accurate where commercial shipping is involved. Some of the areas we cruise don't get the same attention as the more heavily traveled shipping lanes.
NOAA's Charts and Publications page also has a link to download the United States Coast Pilot(r). This is another good source of information. There is also a link there to Online Chart Viewers.
NOAA's Coast Pilot page Link to download the United States Coast Pilot(r).
NOAA's buoy data map for Florida may be useful for up to date information on conditions offshore.
AIS (automatic identification system) is getting very affordable and I have seen an increase in the number of cruisers equipped with class B AIS units. This is especially useful when in close proximity to commercial traffic. I have had Tows call me and ask what type of vessel I was
when approaching a sharp turn. It's a good idea to leave AIS on while at anchor in some cases. MMSI(Maritime Mobile Service Identity) number which can be obtained from Boat US or if you plan to cruise outside the US, you may want to get your MMSI number from the US government by applying for a FCC license. If you have a DSC equipped radio you should already have a MMSI number anyway. If you don't have a GPS equipped radio it will need to acquire position data from a networked GPS. A lot of radios now have AIS receivers which will allow a networked chart-plotter to display AIS targets.
DSC USCG here.
Digital Selective calling information from the United States Coast Guard.