Oscillator astable multi-vibrator with Crystal controller
RF - Oscillator
   An oscillator circuit of this nature. Often used as a clock circuit. This circuit uses a million crystal frequency control with stability. And a circuit that does not use the capacitor or Inductor all.    Each transistor to work, the amplifier with feedback. The Q2 transistors(2N834) to circuits with a gain equal to 1. The gain of the transistor Q1(2N834), as a function of the resistance of the crystal, while the resonance.   By default, the resistance will be less than 22K.This is the feedback resistance of the circuit. Therefore, the gain of the circuit Q1, it is higher than one.     Output …
Very simple voltmeter with ic741
Basic - Tools & Tips
This circuit can be used to measure the voltage to 15 volts.Using the current from the battery 9 volt,At 23 mA only. Input circuit has a diode, to protect the Return terminal. And input impedance of the circuit, were more than 1 M ohm. Heart of the circuit is op – amp number 741.Which acts as a comparator,When the voltage across the pin emitter-bass of the transistor Q1 is a great value.Resistance between the collector and emitter are charged less.Therefore, the voltage at pin 2 of IC1.Therefore less valuable, and the output of IC1 to pay current LED1 light.When we …
A frequency multiplier in depth
RF - Oscillator
Most of the frequency multiplier circuit using IC phase locked loop (PLL).It will increase the frequency to an integer only. But this circuit can double the frequency, in the integer to a fractional number.This circuit has an IC phase locked loop number NE565. It changes frequency as the incoming voltage,Frequency control. That, from the IC Oscillator NE566. IC phase locked loop circuit is in the nature of Demodulator.The output at Pin 7 and is connected to the IC op amp 741. Which is connected in a manner of Voltage-follower circuit. to the driver IC 566 to work. The voltage passing …
Led light bar scan back and forth led two color
Lightings
This circuit is a circuit run on alternating two colors.It uses the 2-color LED with a built-in 3-pin single.This will chase away the glow of each LED until the end.It turns alternating to another color.In any way to the moon on the moon first end, then the LED end of the first LED.Circuit consists of, nand gate ic.Two 10 Counter circuits IC, and IC JK flip flop. Operation of the circuit is divided into 3 sets.It is a set of signal generators, a set of display and control.Set the signal generator is IC1a,and IC1b number 4011 is a signal generator.The …
Timer control 1-15 minutes by Triac 2N6075 and LM555-LM358
Controls & Timers
Most timer circuits. Often used with electrical transformers containing low as 9V and 12V, and use of electrical control relays.but the 1-15 minute timer circuit.It uses a triac instead of electrical control.This can be used with a 220V power house it is not connected to the transformer. Make smaller and easy to use. This circuit is divided into three parts: work special high-voltage level, the scheduling and control electrical appliances. When 220V power supply circuit R1, C1 and ZD1 a special level voltage 220V to rest 10V. The 10V input voltage is power supply to IC1 No. 555. which is …