The tools

Most of my time was spent troubleshooting and repairing the PCB’s in the system.  My ‘best buy’ was a Hako FR-301 de-soldering tool, set to 3.4 temperature setting and using the N61-10 1.6mm standard tip.

The PCB’s are single layer technology and more than 50 years old.  They require a quality temperature controlled de-soldering tool to avoid damaging or lifting the tracks.  When it came to soldering, I used a standard Antex X25, 25 watt soldering Iron.  

Repairing the core memory required the use of a Stereo Microscope, and two pairs of tweezers with sharpened tips to reduce their physical form factor.  More about core memory repair later.

For most of the time I had no requirement for PCB extender boards, however they did prove useful for adjusting pots on the serial interface timing card. I purchased new ones from Douglas Electronics in California.

Of course a good dual trace Oscilloscope is required.  My Chinese Hantek worked well, once I upgraded the firmware to the latest revision.  I also used a current probe for setting up R/W and Inhibit currents.

Current Probe – with thanks to Mark Atherton:

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