Question Fidelity chess challenger - how it retains its programming

[wpshooter]

I have one of the old Fidelity chess challenger dedicated chess game boards from back in the 1970s.

My question is regarding how this thing manages to hold onto/retain its programming.

I have had this thing for about 40 years now (was a birthday gift from my brother) and for long periods of time (some as long as 10 years) the thing would not ever even be plugged in and used. However, whenever during the 40 years that I occasionally get around to dragging it out and plugging it in, it always works/plays chess just fine.

So how does this thing manage to hold onto its programming after such long periods of complete inactivity ?

I would think if it had something like a modern PC CMOS battery, it would have long since gone south.

Is the programming/logic of this thing pretty much good for an indefinite period of time as long as the structure of the game board is intact ?

More info supplied if needed.

Thanks.

 

[Hail The Brain Slug]

The Fidelity Challenger was entirely solid state, so it looks like there is solid state ROM that stores the programming. I can't find a parts list or teardown but it uses the Fairchild F8 microprocessor, which was generally paired with solid state ROM in other applications.

 

[wpshooter]

Isn't it possible for this solid state programming to dissipate or become corrupted after an extremely long period of time ? Thanks.

 

[corkyg]

AFAIK, that would be Read Only Memory (ROM), and that is rather permanent unless subjected to something traumatic, electronically or physically.

This has a pretty good discussion of ROM devices:

Read-only memory - Wikipedia

en.wikipedia.org