This is a photograph of a core storage cabinet.
It contained 256KBytes. There is more about it at
360 Core Storage.

Our interest here is the rectangular white panel
at the top right. We still have it!

Just in passing, below it is power supplies,
to the left of that two gates opened
each containing 64KBytes of core storage,
there were two more gates on the other side.
In between was a central fixed gate
containing circuitry common to all four gates.

This is the panel.
It displayed the state of 25 power supplies,
power and high temperature indicators,
and six rheostats for adjusting the voltages
of the core storage modules.

This is the rear of the panel.
At the top is two rows of indicators
for the 25 power supplies

Below that is two rows of reed relays
that controlled the power supplies,
and below that a mass of wires.

Here is that mass of wires.
Go to Closeup to see the detail
of the hand work involved
in the construction of just this panel
let alone the core storage gates.

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