The answer is yes, and no. Using the software utility available here you can stretch the coverage of your UV-3R Mark II. This
only works on the Mark II (dual watch display) and the new Plus model. There are two options for changing the coverage. You can stretch up from VHF or down from UHF. Only the UHF option seems to work. Now, before you run off and do this, let me pass a few warnings. First of all, the UV-3R is NOT designed to do this, so transmitting at full power on a band your radio was not designed to work on has the potential to fry something. Second of all, most users have put the output power between 1 and 16 milliwatts (yes, milli), and my tests concur with this. It does receive OK on 220, but not as well as it does on 2M or 440. The procedure can be a little complicated, but there is plenty of help at the UV-3R Yahoo Group.
So, does it really work? During my morning commute, my train passes south of my club’s main repeater site. Now this is on a rather high building, in one of the highest points on western Long Island, and is pretty much line-of-site for a 4-5 mile stretch of my train ride. I tested to see if I could key up our 220 machine, and it seems that the effective range was about 4 miles this morning. Now that was just keying the repeater up. I’ll have to check to see if I can actually be HEARD on it. For listening to the 2 or 3 220 repeaters near my office though, it works fine. Also, keep in mind that this was all done with the stock antenna, which is most likely far from optimal at 220 Mhz.
Once again, I can’t stress enough that if you don’t want to risk breaking your radio permanently, don’t try this. So far, my little radio has suffered no ill-effects, but your mileage may vary.