oifvet - Visit this link to the ARRL website.
http://www.arrl.org/FandES/field/regulations/bands.html On this page you can download a PDF version of the frequency band plan chart. On this chart, it shows what frequencies each level of class (Technician, General, Extra) can operate on. As a Technician, you can operate on 6 Meter (50.0Mhz to 54.0Mhz.)
Also, Check out the text version that has some more detailed descriptions of each portion of the band and what mode of transmission is used shown here:
http://www.arrl.org/FandES/field/regulations/bandplan.html
Now, the RT-524 Rig that I have, can operate on Frequencies 30Mhz thru 73 Mhz. Which means that you only need a Techie license to operate this rig. You can not transmit on any other frequency that this radio has available other than the 6 Meter range of 50.0 to 54.0. However, the problem herein lies that the radio (If I'm not mistaken) only transmitts in FM Mode. Furthermore, you only have the option of "New Squelch" which is a factory set 150Hz PL Tone, or "Old Squelch" which is no tone but rather a carrier squelch, or no squelch at all. Finally, the RT-524 (And I'm almost pretty confident that other "Green Radios" are similar) only has a stepping capability of 0.05Mhz. This is a problem in itself because some of the commonly used simplex frequencies are 52.02, 52.04, 52.525, 52.54, 53.02, 53.52 and 53.09. All of which the RT-524 can't tune into.
For instance, the RT-524 can tune to 52.00, 52.05, 52.10, 52.15, 52.20 etc... If your not dead on, they won't hear you, and if they can, you'll sound distorted.
You can receive signals on any frequency that the radio will do, (For instance, the local Highway Patrol office is on 39.45 Mhz I believe) but you can only transmit on the 6 Meter band as allowed by FCC Rules. (Now I could be entirely wrong in this next Sentence) Since most people transmit on SSB (Single Side Band) its hard to find anyone to talk to on FM like this radio does.
But, if you have a group of a fellas who have the "Green Radios" then you could effectively use it while taking part in a convoy or close range applications, like up to a 60 Mile Range Line of Sight I think.
I have not done a whole heck of a lot of research on the capability of this radio or any other for that matter. I just know that my rig works (I verified it by setting up my scanner and transmitting on my rig and was sucessful.) I have heard a conversation on 6 Meters a few months ago, but the other party didn't hear me. I assume that it was because they were using a PL Tone Squelch other than 150 Hz. Also, keep in mind that the "Green Radio" that I have does not have the capability of being used on a traditional repeater (Where you receive on one frequency and transmit on another). Therefore, it's like a simplex radio.
Hopefully, NF6X might chime in as he's pretty well knowledgable on this topic too.
73 - KI6LMI