This card likely originated from a RAF Panavia Tornado aircraft and is presumed to be a component of the inertial navigation system. Printed on the label is the title DATA STORES 2 MK2 along with the project number 3854/77235. The UK MoD NSN is 6605-99-784-8733 and the card was manufactured by Ferranti Scotland. The card contains a variety of high temp, mil spec, ceramic ICs. The chip prefix SN54 denotes mil spec/high reliability. The collection of chips and lack of any microcontroller or processor leads us to believe that this board is responsible for temporarily storing, processing, or manipulating digital data. At the bottom of this page is a table that lists each chip along with a description and function.
There are no components on the back of the board. The overall construction resembles 80s-90s electronics design principles.
We received the following form with this card which indicates it is serviceable. Since the card was in the original box, it appears to be unused and was likely a surplus item. According to the form, the card originated from RAF SEALAND and was also serviced there. The safety warning that reads "contains SSD'S handle with care" is interesting. Perhaps SSDs referred to solid state devices, sensitive storage devices?
| Chip Marking | Family / Manufacturer | Function (Datasheet-Based) | Notes |
|---|---|---|---|
| SN54LS367AJ | Texas Instruments, 54LS TTL | Hex buffer / line driver with three-state outputs | Used for bus buffering and isolation; military temperature range |
| SN54LS04J | Texas Instruments, 54LS TTL | Hex inverter (six NOT gates) | Signal inversion and buffering |
| SN54157J | Texas Instruments, 5400 TTL | Quad 2-to-1 data selector / multiplexer | Standard TTL (non-LS); higher power consumption |
| SN5400J | Texas Instruments, 5400 TTL | Quad 2-input NAND gate | Basic combinational logic element |
| SN5495AJ | Texas Instruments, 5400 TTL | 4-bit bidirectional shift register with parallel load | Serial-to-parallel and parallel-to-serial data handling |
| SN54123J | Texas Instruments, 5400 TTL | Dual retriggerable monostable multivibrator | Pulse generation, stretching, and timing control |
| SN5402J | Texas Instruments, 5400 TTL | Quad 2-input NOR gate | Used for combinational logic and gating |
| SN54175J | Texas Instruments, 5400 TTL | Quad D-type flip-flop with asynchronous clear | Temporary data storage and synchronization |
| SN54LS83AJ | Texas Instruments, 54LS TTL | 4-bit binary full adder with carry | Arithmetic addition of two 4-bit words |
| M1-6551-2 | Harris | Custom logic device | No public documentation |
| 914C153X2PE | Vishay | Resistor network | No public documentation |