Vacuum tube type SR1407
||Printed in silver on top of the glass envelope.
||Handwritten vertically in silver ink on the glass envelope.
||Stamped in green ink near the bottom of the glass envelope.
overall: 2 7/8 in x 1 1/8 in x 1 1/8 in
This is a Sylvania developmental power pentode in a glass envelope with an eight-pin loctal base. This is a spare tube for Bus Driver Arithmetic Rack S/N 4.
Gift of the Digital Equipment Corporation