Most of the cards a symmetric around the center for the two drives. A few cards are shared between both drives. At the left is the type 725 reel motor power supply. It produces 18 and 38 volts. The rest of the voltages are externally provided.
Cards from left to right:
Two G848 motor drive cards
G859 40 Hz motor drive oscillator.
M941 Jumper card.
Should be G742 jumper card, wasn't in drive when I got it so I built a replacement.
Empty, used for daisy chaining drives
Should be M908 drive control cable, I had to build an equivalent.
M040 solenoid driver for head relays and select status.
G851 head relays. Connects head to common bus when drive selected.
Empty, used for daisy chaining drives
Should be W032 drive cable, I had to build a replacement.
G851 again
G888 Head Manchester read/write amplifiers.
G888
M040
M117 NAND gates card for various drive logic
Rest same as other side
There is a second row of cards not visible in this picture but can be seen some in this picture. ( 66K) .
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