AUDIBLE_OHMMETER_1

Published:2009/7/20 20:11:00 Author:Jessie | From:SeekIC

Volume and/or pitch of one-transistor audio oscillator varies with resistance across test terminals, to give audible indication of continuity and relative resistance without looking at meter. Can also be used as transistor and diode tester, signal injector, code practice oscillator, and CW monitor. Oscillator uses transistor-type transformer having center tapped windings, connected as shown to give three-winding transformer. Operates from two 1.5-V cells in series. Will respond to resistance values from short to about 100K. Volume in-creases and pitch rises as resistance is increased. For very low resistance, tone resembles croaking of frog.-Build the EI Sapo Tester, 73 Magazine, Dec. 1977, p 184-185.



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