I am debugging a Beta Products pcb part number 304330. It has 6 of these chips which which are the only IC's on the board. I need to know the pinout to be able to create a test fixture to verify operation and possible re-design the obsolete board. The date codes make me believe this board was make in 1985 and the chips have date code of 8450. But I can't find the data sheet on-line. I found one site that calls it a quad dual-input NAND gate which is believable, but I couldn't determine which pins were inputs and which were outputs based on voltage readings, so I am not sure this is true.
A schematic of the 304330 board would be ideal.
Any help or suggestions where to look?