write-only memory: n. The obvious antonym to `read-only
memory'. Out of frustration with the long and seemingly useless
chain of approvals required of component specifications, during
which no actual checking seemed to occur, an engineer at Signetics
once created a specification for a write-only memory and included it
with a bunch of other specifications to be approved. This inclusion
came to the attention of Signetics management only when regular
customers started calling and asking for pricing information.
Signetics published a corrected edition of the data book and
requested the return of the `erroneous' ones. Later, around 1974,
Signetics bought a double-page spread in "Electronics" magazine's
April issue and used the spec as an April Fools' Day joke. Instead
of the more conventional characteristic curves, the 25120 "fully
encoded, 9046 x N, Random Access, write-only-memory" data sheet
included diagrams of "bit capacity vs. Temp.", "Iff vs. Vff",
"Number of pins remaining vs. number of socket insertions", and "AQL
vs. selling price". The 25120 required a 6.3 VAC VFF supply, a +10V
VCC, and VDD of 0V, +/- 2%.
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