A 30 year old antenna? Geesh, it's time to bite the billet and replace your antenna, rotator and cabling with all-new equipment! What you have is probably so corroded and weathered that it probably isn't picking up much of anything. Remember that an amplifier can only amplify what the antenna sees, and, given how close to the DC transmitters you are, just about any amplifier is likely to overload on the strong signals. Since you also have access to the Baltimore channels from your location, I would use a Winegard HD-7696P antenna, all new RG-6u coaxial cabling, a Channel Master 9521a automatic rotator with new control cabling. When you are done, you will have access to more TV channels that you can possibly ever watch, including duplicates of the major network channels from DC and Baltimore. Here are the specs, and a good antenna installation guide.
http://winegard.com/kbase/upload/HD7696P.pdfhttp://channelmaster.com/product-overvi ... 8&catID=34http://manuals.solidsignal.com/AntInstallGuide.pdf