RGB Question

Ok, I have a question about this monitor i have. Its a Tandy RGB-11. So I've been using the composite input for a while, very good monitor, but I've been trying to get the RGB input to work. It says "TTL RGB" for the input. There's another jack (with plastic over it, i assume there's no actual jack under it) labelled "RGB Lin." So, my question is, whats the difference? Can I use this monitor for a supergun, using the TTL RGB input?

Here's a little info (DIN 45326):
http://www.hut.fi/Misc/Electronics/circuits/vga2tv/rgb_pinouts.html

thanks!

TTL RGB is a digital input (transistor-transistor logic)
LIN RGB is a linear analog input
Not compatable