Ultra-sonic sound processing with schema electronic audio
Parts List
SEMICONDUCTORS ---------------------------------------------------- IC1 567 phase-locked loop, integrated circuit U1 LM386 audio power amplifier, ic Q1, Q2 2N391M NPN transistor Q3 MPF102 JFET transistor RESISTORS (All fixed resistors are 1/4 watt, 5% units.) ---------------------------------------------------- R1, R2 220,000 ohm R3-R6 2,200 ohm R7 1,000 ohm RS, R14 270 ohm R9 100,000 ohm R10 4,700 ohm R11 10,000 ohm R12 50,000 ohm, potentiometer R13 10,000 ohm, potentiometer CAPACITORS -------------------------------------------------- C1, C2, C5 0.01 microF, Mylar C3 0.047 microF, Mylar C4 0.0022 microF. Mylar C6, C7, C11, C12 0.1 microF, ceramic-disc C8 10 microF, 16 WVDC, electrolytic C9 47 microF, 16 WVDC, electrolytic C10 470 microF 16 WVDC, electrolytic
Ultra sound is captured by the microphone 1 and through two stages of amplification in the P1 and P2 will produce a single frequency, which is produced by the LM567 oscillator U1. LM567 is a tone decoder but the input control voltage.
Two signals in Q3 mixed to produce a good signal in the audio range and higher frequencies are then filtered.
The remaining audio signal through the last stage of controlled (R13) amplification of the LM386 at U2 before available to the AUDIO OUT output.
This consists of two times the frequency of voltage controlled oscillator (VCO) and divider which sets the reference signal for phase and amplitude detector. Phase detector and VCO phase-locked to form the loop (PLL) that locks to the input signal frequency within the range VCO control. “
