I will need a converter box to convert OTA digital signals for viewing on my analog TV. Can I use an antenna with built in amplifier, or buy an amplifier to connect to my current UHF rooftop antenna, without damaging the converter box?
... with the caveat that most antenna amplifiers really don't help digital TV signals all that much. Try it without one first, and if you do get one, don't just spring for the blister pack cheapo. Get a high-quality Channel Master or something.