This is a very rare chip from the dawn of the microprocessor age. It is an attractive white ceramic package with gold leads and a gold framed UV window over the die itself. This particular package has never beein installed, it just sat in its black foam from hwen it was delivered, then surplused, then in a box given to me by a co-worker sometime in the 90s, and now here it is. Notice in the closeup how the die is not square nor centered on its pad under the window - the ICs of that era had a lot of hand wori, probably the gold leads were bonded by hand.
The C8702 is one of the earliest UV PROMS available, the data sheet is on line Time - 1.3 f-tsec Max.• Fast Programming - 2 Minutes for All 2048 Bits• Fully Decoded, 256 x 8 Organization• Static MOS- No Clocks Required• Inputs and Outputs TTL Compatible• Three-State Output - OR-Tie Capability• Simple Memory Expansion Chip Select Input LeadThe 8702A is a 256 word by 8 bit electrically programmable ROM ideally suited for microcomputer system development where fast turn-around and pattern experimentation are important. The 8702A undergoes complete programming and functional testing on each bit position prior to shipment, thus insuring 100% programmability.The 8702A is packaged in a 24 pin dual-in line package with a transparent quartz lid. The transparent quartz lid allows the user to expose the chip to ultraviolet light to erase the bit pattern. A new pattern can then be written into the device. This procedure can be repeated as many times as required.The circuitry of the 8702A is entirely static; no docks are required.A pin-for-pin metal mask programmed ROM, the Intel 8302, is ideal for large volume production runs of systems initially using the 8702A.The 8702A is fabricated with silicon gate technology. This low threshold technology allows the design and production of higher performance MOS circuits and provides a higher functional density on a monolithic chip than conventional MOS technologies.
from computerhistory.org, we have some of the back story:
Dawon Kahng and Simon Sze of Bell Labs described in 1967 how the floating gate of an MOS semiconductor device could be used for the cell of a reprogrammable ROM. In the early 1970s, General Instruments, Hicksville, NY adapted a metal nitride oxide semiconductor (MNOS) process to build small electrically-alterable EAROMs for TV tuners. 1971 Intel announced the 1702, a 2048-bit user-erasable, PROM (EPROM) designed by Dov Frohman that could be reused multiple times by erasing the pattern with ultra-violet light. Generations of UV EPROMs with multi-million bits of storage from Intel and others found wide application for storing and modifying program codes as firmware in microprocessor-based system designs.

Note to me: computer hutch, Bin 3

I normally ship within 24hours of your order, but the post office does not alwaysinitiate tracking when Iput the packages in the drop off box.