Power Amplifier IC 74AC244 DIL
Replacement Power Amplifier for WSPR Transmitters LP1 and Desktop models.
The Desktop model Hardware version 2.6 or higher use these and the LP1 Hardware model 2.5 or higher also use these.
Like all DIL ICs they will need to have the pins bent slightly inwards to fit in the socket. They should go 90 degrees straight down from the body when they are correctly bent before you attempt insertion.