Devices in the GF401xx family have an unusual construction which resembles the metal can packages of Western Electric power transistors from the same era, but instead of using the long thin leads seen on most Western Electric transistors, GF401xx devices have 11 heavy square pins. This basic configuration is replicated in the Western Electric 112946xx series of integrated circuits, monolithic devices which are direct replacements for the GF401xx series. This package type is exclusive to GF401xx- and 112946xx-series devices, and appears to have never been used commercially.
The GF401xx series devices are among the rarest and most unusual semiconductors ever produced by Western Electric, as they are the only family of Western Electric semiconductors known to be constructed from multiple discrete transistors and diodes. Such technology was used for only a short period of time, between the era of discrete semiconductors and the era of monolithic integrated circuits.
Very few of the GF401xx devices are known to exist. The Smithsonian Institution has at least four examples of these devices, in part numbers GF40139, GF40140, GF40142 and GF40164, with date codes from 1968 and 1969. The devices held by the Smithsonian originated from a Bell Labs employee, and at least one of them has had its lid removed.
We obtained a total of 25 GF401xx devices from a military electronics surplus reseller in 2008, nine of which have either been released to private collectors, or are slated for release. No other examples of these devices are known from any other collections. The devices held by the VTA are as follows:
Western Electric GF40139 40A66 - 4 pieces
Western Electric GF40142 39A66 - 2 pieces
Western Electric GF40142 40A66 - 1 piece
Western Electric GF40142 14F69 - 1 piece
Western Electric GF40143 40A66 - 4 pieces
Western Electric GF40145 39A66 - 4 pieces
Previously released to private collectors:
Western Electric GF40143 40A66 - 2 pieces released to private collector #1 (2009-01-01)
Western Electric GF40145 39A66 - 1 piece released to private collector #2 (2010-02-06)
Western Electric GF40145 39A66 - 1 piece released to private collector #3 (2010-03-16)
Available for release to private collectors:
Western Electric GF40139 40A66 - 1 piece currently available for purchase
Western Electric GF40143 40A66 - 1 piece currently available for purchase
Western Electric GF40145 39A66 - 3 pieces currently available for purchase
We also obtained 10 examples of the second-generation 112946xx monolithic devices. These devices were produced by Western Electric and Motorola, and are not currently known from any other collections. The devices held by the VTA are as follows:
Western Electric 11294641 7032, red print - 2 pieces
Western Electric 11294644 7227, green print - 1 piece
Motorola 11294629 7111, black print - 1 piece
Motorola 11294639 7124, black print - 1 piece
Motorola 11294641 7110, black print - 1 piece
Motorola 11294641 7118, black print - 1 piece
Motorola 11294644 7115, black print - 1 piece
Motorola 11294650 7212, green print - 1 piece
Motorola 11294651 7050A, black print - 1 piece
Additionally, we have two engineering samples of these devices. The first sample includes a GF401xx device and its direct replacement, a 112946xx device. Both devices are lidless and their part numbers are unknown. The second engineering sample includes two examples of Western Electric 11294629, date code 6812, black print. One device is lidless, while the other is complete.
Western Electric GF40143 hybrid integrated circuit.
GF40143, internal construction.
GF40139 hybrid integrated circuit.
GF40142 hybrid integrated circuit.
GF40145 hybrid integrated circuit.
