DIY audio amplifiers circuit diagram electronics projects and other related audio projects like : power amplifiers, audio systems, audio filters, vu meters, tone control, audio equalizers and more .
A class A amplifier can be designed using a TDA1034 as an preamplifier and final stage made with transistors, can be achieved like in electronic diagram below.
An alarm with delayed trigger can be made using electronic scheme below. This electronic alarm becomes operational after about 30 after the input becomes 0 emitting four sounds at one second interval. This operation is repeated every thirty seconds until the input signal reaches a logic state 1 again.
The circuit is realized with binary counters with 14 stages, with oscillator built realized in CMOS technology type 4060. Oscillator frequency, f is determined by following formula f = 1/4R3C1, where f is in Hz, in ohms R3 and C1 in farads.
