Matt:
Upon checking your TVFool report, if you want reception of both Philadelphia and Baltimore stations (which are in different directions), the best way is to use either a combination antenna, or separate antennas on the same mast, on a rotor. Your TVFool report says that, in addition to your UHF stations, you have several VHF-high stations available to you (channels 8, 11, 12 and 13) and one VHF-low station (channel 6). To add the VHF low and high capability, you have a few different options:
1 - Replace your 4228 with a Winegard HD8200U antenna, on a rotor:
http://www.solidsignal.com/pview.asp...0Antennas&sku=
The 8200 is a very good long-range antenna that covers VHF-low (channels 2-6), VHF-high (channels 7-13) and UHF (channels 14-51), and its advantage is that it's a very good all-in-one solution. The disadvantage is that it's a very large antenna (168" long by 111" wide at its rearmost reflector). Depending on your home situation, the antenna may simply be too large.
2 - Since your 4228 is already one of the best UHF antennas available, you could use that for your UHF reception and add an appropriate VHF antenna about three feet below the 4228 on the same mast, all on a rotor. Many people prefer separate VHF and UHF antennas because they have better gain than all but the very largest VHF-UHF combination antennas, and since the individual antennas are somewhat smaller (with the VHF-only antennas having a flat configuration), they tend to look smaller up on the roof, even though you're using two antennas. You'd combine the UHF and VHF antennas together up at the mast into a single downlead using a UVSJ:
http://www.solidsignal.com/pview.asp...Combiners&sku=
But what VHF antenna to pick? Here, you have a few more options:
2a - Add a Winegard HD 5030 about three feet below your 4228 on the same mast, all on a rotor. The HD 5030 is a good antenna with reception capability for both VHF-low and VHF-high stations:
http://www.solidsignal.com/pview.asp...u=615798398156
One disadvantage of the HD 5030 might be its fairly large size (119.5" long by 111" wide at its rearmost reflector, tapered in its width toward the front). Another possible disdvantage is that its gain might not be sufficient for your Baltimore channels 11 and 13 (a close call), because your TVFool dB NM figures for those channels are -4.8 and -5.6 respectively (which are somewhat weak). If you check out the gain figures for the HD 5030 (by clicking on the "Specifications" tab on the website page), you'll see that it has 7.7 and 8.2 dB gain for channels 11 and 13 (decent, but not the best). However, it might work just fine (others might chime in with their thoughts on this issue), and would be the quickest and least expensive overall solution if it worked.
2b - Add a Winegard YA-1713 instead of an HD 5030 (again about three feet below your 4228 on the same mast, all on a rotor), but that antenna covers VHF-high only (channels 7-13):
http://www.solidsignal.com/pview.asp...u=615798304867
The YA-1713 is quite a bit smaller (100" long by around 35"-ish at its rearmost reflector) than the HD 5030, so it would look less unwieldy up on the roof. Also, if you look at the dB gain figures for the YA-1713 (again, by clicking on the "Specifications" tab on the website page), you'll notice that the YA-1713 has more gain over the VHF-high band (10.0 and 10.3 dB gain figures for channels 11 and 13) than the HD 5030. This would tend to ensure good reception on channels 11 and 13, over using the HD 5030. But then you'd be giving up channel 6 from Philadelphia because the YA-1713 doesn't have VHF-low reception capability.
2c - Add a Winegard YA-1713 plus a separate channel 6 antenna. Even though this might sound like too much hassle, it might be a good option. The VHF-low channels require the longest-length elements on any VHF antenna, making it large. Since channel 6 is your only VHF-low station, a separate VHF-low antenna wouldn't need to be on a rotor, and can just be pointed toward Philadelphia in a fixed position. In addition, channel 6 is the strongest station on your TVFool report. In your situation, you might get away with adding the YA-1713 to your 4228 outside on a rotor (combined with a UVSJ at the mast) for your VHF-high plus UHF stations, and then add a Winegard YA-6260 (for channel 6 only) in your attic, if you have one:
http://www.solidsignal.com/pview.asp...u=615798304874
The 6260 is a fairly big antenna (87" long by 110" wide at its rearmost reflector), so you'd have to have room for it in your attic. But the advantage is that you'd be hiding your widest-width antenna inside your attic. You'd run the combined line from the UVSJ (connecting the 4228 and the YA-1713) into the attic and combine with the YA-6260 with an HLSJ, and then run that single output down to your tv:
http://www.solidsignal.com/pview.asp...Splitters&sku=
The advantage of this option is very good gain across all desired channels. The disadvantage of this option is that if the YA-6260 didn't receive channel 6 from your attic, you'd be forced to put it outside, and having three antennas together outside is probably too much, and ruins the advantage of hiding your VHF-low antenna.
I would try to get the best reception first without any amplifier and then add an amp at the end only if absolutely necessary.
Hope this is helpful - good luck!