SIGNAL INJECTOR

SIGNAL INJECTOR

This circuit is rich in harmonics and is ideal for testing amplifier circuits. To find a fault in an amplifier, connect the earth clip to the 0v rail and move through each stage, starting at the speaker. An increase in volume should be heard at each preceding stage. This Injects will also go through the IF stages of radios and FM sound sections in TV's.

source : http://www.talkingelectronics.com.au/projects/200TrCcts/200TrCcts.html