Your points, Karen, on preservation, conservation, and restoration are well made.

It also seems to me there are several “classes” or “levels” of restoration. Some examples:

Get it working
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When I restore a piece of vintage test equipment, my goal is typically to get it running so I can put it to work. For example, I recently acquired several vintage Wilson hard drive testers. If one was not working properly, I replaced parts using vintage or modern components. My goal was not to have/show a tester as a historical object, but rather to use it as a working tool.

Restoration – maintain it’s vintage status
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In this case, a restoration must only use modules, peripherals and parts which are age and configuration appropriate. For instance, I acquired a DEC PDP 11/34 and restored it carefully. When it could pass all diagnostics, I upgraded it with cache memory, additional RAM memory, added two RL02 cartridge disks, and a third party SCSI controller. All the boards and peripherals used were age appropriate to the 11/34; i.e., one could have expected to see an 11/34 in the seventies with this configuration.

Restoration – of a historical artifact
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This is the most demanding level of restoration. We vintage computer collectors rarely restore to this level. The goal is to restore a system with as little change to the artifact as possible. This means using replacement parts which are the same type and vintage as those one is replacing and insuring that any changes made can be reversed.

Those of us who had the privilege of restoring the CHM’s PDP-1 did so at this level.

The entire restoration process was carefully defined by the Restoration Team. We studied the history, uses and architecture of the PDP-1. We discussed the alternative restoration processes by the hour.

Recognizing we were dealing with a rare artifact, we created a restoration process which insured to the best of our ability that we would not have an event which could damage the system in any way.

We also initiated a system log in which every action we took and changes to our process were logged in detail.

A critical element in our restoration process was that every part which was replaced was put into a plastic bag with a tag identifying its origin module’s location. The replacement part was identified on the module with a “dot” of red nail polish. By doing so, we were able to insure that all our “changes” were reversible.

If the PDP-1 Team had merely had the charter to “get the PDP-1 working” we could have done so a LOT more quickly.

However, the process we used insured that the PDP-1 not only “worked”, but maintained its status as an accurate historical artifact.

I am a strong advocate of future CHM restorations and agree with the CHM’s strategy of being “dedicated to collecting and preserving at least one unaltered example of the major technological advances of the Information Age”.

While some may see this as too restrictive, from a practical perspective it’s actually quite broad. Restoration of historical artifacts is very doable – but a necessarily careful and sometimes time consuming process.