I presume when you indicate PBS, you are having trouble with WGVK. They are one of the few TV stations in the country to broadcast DTV in the low VHF band. Channel 5 in this case. Neither of the antennas you have are designed to receive the low VHF channels (2 - 6). As you have experienced, an antenna will still receive some signal on frequencies it's not designed for.
Antennas Direct and Antennacraft each offers a L-VHF antenna,
model V4 and
model Y526. These antennas are specifically designed to receive channels 2 through 6.
As the leafs start to come out, you will see signal levels drop. The HD7694P should be able to provide the gain needed to offset that loss. The additional gain on channel 7 should have stabilized reception of WOOD presuming it is aimed in that direction.
You will need a
HLSJ.
Edited: As ADTech points out, most HLSJs will pass UHF through the high port. Thanks ADTech.