Slightly revised version of the 1970 KC-6060, the KC-6060A offered and still does hours and even days of marvelling at waveforms drawing patterns on the green-ish 3" tube !
From 0,1V peak-to-peak, to left or right waveforms, stereo spread displays, monaural lines to FM multipath... plus a built-in 1Khz oscillator, a built-in sweep generator from 10Hz to 100Khz and, of course, solid-state circuitry.
All the diagnostics the fascinated hifi buffs would spend hours to comment and interpret.
The next step was going pro and using the real Trio/Kenwood 'scopes for the pros - and knowing what stinkers most amplifiers and tuners really are.
And that isn't as much fun as not fully understanding the little green alien messages on the tube !
Innocence (and imagination) is bliss.