Electronic schematics, circuit designs
Universal line amplifier
A line amplifier is a circuit which is good to have around to adjust a the line or raise the level. This may be necessary during a recording or in a broadcasting system. In addition with some of these amplifiers can be built a mixer line.
Amplifier input can resist to high voltages. The volume potentiometer from input has his “cold” terminal not to the ground but to the first amplifier output. Because the signal is dephased from that at the entrance, amplifier gain negative reaction by P1. In this case amplification is inversely proportional to the size of input signal. It may be accepted at the entrance even a signal taken directly from
Read the rest of this entry »
Capacitor meter
The capacitor meter presented here can measure capacities between 100pF and 1uF on five areas of measurement, more we can say multimeter or tester.
Circuit consists of an oscillator with variable frequency, a divided frequency and measurement stage. The Oscillator is based on a inversor from a 74HC14 and generates a frequency f inversely proportional to the Cx placed between terminals.
Approximate relationship is:
f = 1.2 * R * Cx,
where R depends on the position of S1. With the values of the schematic, the frequency is situated between 240Hz (Cx = 1uF) and 12kHz (Cx = 100pF).
During a half periods of each signal his exit from IC3, C2 is loading by T1. During the other half of the period, T2 is brought Conducted by the signal, so that C2 will be shortcircuited. In this way, the maximum voltage C2 depends on the frequency signal. Tension is taken over by repeter IC1b and integrated R1-C1.
Read the rest of this entry »
Talk Over circuit schematic
A very usefull talk over circuit which you can use in your radio stations, club or anywhere you want to speak over music without any movement of potentiometers. Just talk in your microphone and the music level will drop accordingly to your voice.
Talk-over circuit schematic:
Read the rest of this entry »
