Wasp 4069 - buffered or not?

[Haible Juergen]

Hi again, and happy new year.

Short question: Could anybody who owns an EDP Wasp could check
if the CMOS IC that is used for analogue amplifiers is buffered or
unbuffered 
type? 
You'd have to look for a chip with the number 4069 (with some prefix)
on it, and I am interested in the letters directly after the "4069".
I'd expect either "A", "UB" (both unbuffered) or "B" (buffered).

Thanks,

JH.