4606 System Building Block
"PULSE AMPLIFIER" on solder side. Portion of one land pattern has peeled up off PCB. Two indecipherable script letters written in orange crayon on both solder side and component side: possibly "ry".
Digital Equipment Corporation (DEC)
||4606F on solder side
1/2 x 7 x 4 1/2 in.
Component: circuit board / module