Simple Telephone Ring Amplifier circuits
The telephone repeater circuit or The call signal peripheral circuit to the loud than the original,with a buzzer or a electric bell, to increase loud sound Read more
4 simple transistor tester circuits
This is the Transistor tester circuit into PCB. When your project do not works, the tester electronic parts or component be what need very much. Read more
16 keys keyboard encoder circuit using 74C922N
It may be difficult. In the design of the BCD signal generator circuit by pressing a key. Here is how you make a keyboard encoder circuit for 16 keypads. Read more
18V DC power supply circuit using LM7818
When I need to use DC regulator power supply 18V 1A for the transistors pre tone control circuits. Read more
Audio peak limiter circuit to improve input signal
The simple audio signal overload protection circuit. Why use it? it will protect input of power amplifier away high amplitude, more than1Vrms. Easy circuit! Read more