[Heathkit] SB-634 modification, WB4VVF Accu Keyer installed

[Heinz und Hannelore Breuer]

Hi,

I checked one of my SB-634 and it has a mod. There is a pcb mounted
vertically behind the main pcb with "WB4VVF" on it. A Google search
found it to be the Accu Keyer from QST August 1973. Is this of any use
or should I remove it?

73
Heinz DH2FA, KM5VT