As I have just finished a writeup on the E series (the newer version) I thought I would also do a writeup on the older RL series. I do not think these are in production anymore. If I recall correctly, they were about the last marine product put out by Raytheon (which split off to become Raymarine). However, since many of the older boats still have these units, some review might be helpful to boat buyers when the vessel they are purchasing has these units. Please excuse any unintentional mistakes in this writeup since I have not actually used these for several years now.
RL 70 (CRC)
Would it be fair to call it fairly trend setting for its time? I think so. In my opinion, they held the market then and the Garmin products were not well developed or sought after... if they were even around. The leading competitor in my opinion was probably Furuno, whose specialization in radar, really carried them forward.
The RL series came in monochrome black and white, or color (if designated in C). The 70 stood for 7 inch display. They were taunted as truly daylight viewable - especially the color series. I put a color series at the Nav and had a B&W at the helm. This probably was a mistake because the color unit gave much better resolution. I always found the B&W unit difficult to see in direct daylight, though not as bad if it was not really bright. The color unit was by far superior.
Many of the functions that were present on that unit were carried over to the new E series. You can read above what those are. Some exceptions that I am aware of are the overlay for radar, camera, and weather ability. The course plotting and waypoint settings all work(ed) similar to the new E series. Those that are upgrading will easily navigate through the E/C series units.
I have to say that there are a few differences that make the E/C series units well superior to the older units. They are:
1) Daylight viewable. Much better resolution and brightness.
2) Scrolling. This is a big one. I always found the R series slow to scroll across the screen. The refresh took a while too.
3) The radar overlay. To the best of my knowledge, the old units did not do that. If I am wrong, I apologize.
4) MARPA. This stands for Mini Automatic Radar Plotting Aid. This is a function that was once only utilized by commercial ships to overlay up to X number of contacts (the E series is limited to 10, as I recall) and plot their course against your heading. They warn you if there is the potential for a collision. To the best of my knowledge, the old units would not do this. This is a nice function to have when crossing shipping lanes or on busy harbors.
5) AIS. Not sure they would take that input. I am not sure it was around then (which it may have been) but I had not heard of it.
I cannot think of a lot of other differences. I will say that I did have some problems early on with my units suddenly locking up. They ended up replacing the unit to get the problem resolved. Other than that, it worked fine and was an awesome tool to have on board.