Most of the information about 1960s-era fuzz boxes on this website comes from anecdotes, press cuttings & advertisements, and from historical photos. However, when it comes to examining circuits and verifying production dates of specific pedals, the principal source material is often pedals themselves.
I have an ever-growing collection of original fuzz boxes from the 1960s, but this pales in comparison to the database of photos of surviving pedals belonging to other people that I have catalogued over the course of more than a decade.
If any readers also happen to have any 1960s-era fuzz pedals, then any photo contributions towards this research would be greatly appreciated. In turn I happily provide insight about fuzz boxes that are submitted, ranging from general historical & technical information about the model in question, through to ascertaining its originality & authenticity.