Occasionally contributions to electronics education are received from overseas. This is one such piece received recently from the United States. Although the demonstration described is common in schools, it is the very fact that there is a different terminology and approach within, this article that we include it in the journal. The American use of English has deliberately been left unedited. The teaching of this topic is aimed at ‘two-year college level students’, or in the English system years 7 and 9. it is hoped, in this unedited version, that the article informs and entertains and that the reader can use the ideas for their teaching.