[1] From the age of 11 he attended the Nyborg Realskole (a private school with partial state funding), where he developed interests in chemistry, biochemistry and ornithology.

In the garden of the Kullerup rectory he carefully recorded in musical notation the characteristic song and variations of over 20 different songbirds.

[1] Having assembled a crystal radio receiver and transmitter, he once transmitted his mother Gunnild playing Schumann on her grand piano.

His biographers suggest that this may have been "an early manifestation of what later became a serious research activity, namely the construction of the analog parallel synthesizer at the Institute of Phonetics in the late sixties.

Having read Bernhard Karlgren’s introductory textbook on Chinese and a grammar of Old Norse, Rischel raised rabbits and sold them to earn the money to purchase a copy of Danmarks Runeinskrifter, a scholarly three-volume work on Danish runes edited by Lis Jacobsen and Erik Moltke and published during World War II.