Core memory experiments

I got a single core memory plane from EPay:

The core plane laminated between two sheets of plastic, four quadrants of cores with the drive windings along all four edges and new leads soldered to the corners.

After some microscopic introspection I soldered some new wires to the panel:

Colors	Type	Resistance
Orange	Sense? Runs all cores diagonally	17 ohm
Blue	Inhibit? Runs all cores diagonally	11.51 ohm
Yellow	Address X	1.98 ohm
Green	Address Y	2.01 ohm

To be able to put sufficient current in the X and Y wires I built a simple full bridge amplifier to drive one of the X/Y wires, and a small 100x amplifier to detect the pulse from the sense wire:

The driver: an NE5532 pair feeding a TIP31C and TIP32C bridge for the X/Y wire, with a second NE5532 as a 100x sense amplifier below it.

which will receive a signal from my signal generator so that we can see the cores flip with a bit of luck.

I sent a 1kHz sine pulse train of 10 periods separated by 100ms pause as to not overload the cores. This resulted in this:

Ten cycles of a 1kHz burst. Yellow is the generator, blue and green the two bridge outputs, and the sharp spikes on the magenta sense trace are the cores flipping.

The yellow line is the function generator input. Blue and green are the outputs of the bridge amplifier (referenced to gnd). The purple trace is the sense output, and we see the core nicely flipping