In the second half of the 70 such devices were in at the height of fashion. The guys walked down the street, holding the elbow flexed at such a mafon and it was cool.
The size of such was, remember, a little smaller than a standard laptop. A classmate was in the 75m, but I'm not lucky ...
There was another Sputnik-404, something else, but that was not it. The best, no doubt, were the Spring-206 and-302 Electronics