Circuit Schematic learn

A lot of controversy exists among amateur fishermen as to the effectiveness of "fish-callers". Some swear by them, others just shake their heads. Here’s an inexpensive way of finding out. The two·transistor circuit drives the speaker.
Varying the two potentiometers produces a wide variety of sounds. You may be lucky and hit on one that will bring in the big ones. An inexpensive waterproof housing is thick walled polythene bag with a few lead sinkers inside. An on-off toggle switch can be manipulated without opening the bag when switching power on and off. The bag opening is sealed with good quality electrical tape to make system waterproof. Tape seal should be renewed after each use.