Hi Ed. the zener is VR4341, Tek part No. 152-0166-00. I'm not sure if the
zener is used as a reference voltage. I believe it is part of the
horizontal amp circuit and bridges the two balanced amplifiers that lead to
the deflection plates. The part I purchased from Mouser Manufacturer Part #
1N5234B-TR. I'm not sure if this is a direct replacement for the Tek part
number. I guess I could google the part number and see what the equivalent
component is.
