TREE

This tiny conductivity tester works with LM 3909. The tester makes a beeping sound if the resistance between the test probes between 0 and 100 O lies. Due to the volume of the beep, the resistance between the test probes can be determined. Audio Lm 3909 IC-conduction tester Circuit Diagram Parts List      R1 = 1 k      C1 = 10 uF      C2 = 100 nF      LS = Loudspeaker 12 to 16 Ω      IC1 = LM 3909

Simple Condenser Pre Amplifier LM 1458 Circuit Diagram. This is the very Simple Condenser Pre Amplifier LM 1458 Circuit Diagram. This circuit using a LM1458 dual op amp IC. The circuit takes the audio signal rom the condenser microphone and amplifier it, so you can use the microphone as the input to some device which wouldn’t normally accept microphone level signals . Simple Condenser Pre Amplifier LM 1458 Circuit Diagram The circuit requires a 6-9 volt supply. Output of the microphone amplifier can be made variable by connecting a 10kΩ potentiometer . Circuit’s gain can be increased by men perbesar the value of 47K, depending on the input sensitivity of the main amplifier system. The microphone should be housed in a small round enclosure. Parts List Q1,Q2    : LM1458 Op-Amp R1,R2,R3 : 4.7k ohm resistor R4, R5   : 10k ohm resistor R6,R7    : 47k ohm resistor C1,      : 0.22uF ceramic capacitor C2    ...