Just a suggestion, I've done similar and I've found that because a museum display is static, untouched, that actually a visibly-accurate, animated mock-up is better, one that appears to the casual viewer to be very busy on a problem, with moving-coil meters swinging, knobs rotating, indicator bulbs fading up and down, a 'ding' solenoid bell, an internally-looped chart recorder... you can even coordinate a dangerous prediction with meters and chart recorders bouncing off their end-stops with red lights throbbing...
Participation is good, you could give them one nice strong pot to turn against a dial labelled 'radius' and have it show 'area of the circle' on a meter. Feed a pot into a comparator and get them to try so set the output mid-way (which of course they can never do but it amuses them to try!) then explain its operation and where it would have an application.
Present Joe Public with a perfect replica of a Heathkit HC-1, in a glass case, doing nothing, and they will glance and move on. Give them an animated or interactive display and they shout their kids over to see it...
![Smiley :)](https://www.eevblog.com/forum/Smileys/default/smiley.gif)
Its rather like the animatronics that attract customers into those amazing German Christmas stores, but applied to demonstrate history and the technology of its time.
As I said, its just a suggestion, based on our own presentations.
Cheers
Phil