Voltase hobby: wave

Sunday, October 5, 2014

2SC1061 2N3055 LM358 CD4047 100W Square wave Inverter

This is AC Inverter. Input 12VDC from car battery to output 220V AC 50Hz or 60Hz at Square wave signal.
The main part is IC CD4047 and IC LM358 and Transistor 2SC1061 and 2N3055.
The transformer is 12V-012V Primary : 220V Secondary.
and current 3A up for power output than 100W.
Note:
C1 = 0.1uf metalized-film capacitor, 5% tolerance.
R1 = 47K for 50Hz output, 39K for 60Hz output.

Thursday, September 4, 2014

3 φ Full Wave Controlled Rectifier circuit to control DC Motor Speed

In the given Block and schema diagram of a 3 φ Full Wave Controlled Rectifier schema to control DC shunt motor is shown.

In this schema diagram the field and armature diagram are connected through three phase full wave Controlled rectifier schema.

In three phase supply, each phase is different form other one in 120°, therefore at each out put terminal a, b, & c give the following Sine wave voltage.

Through the three phase controlled rectifier, the three phase supply is converted to a DC and provided to the armature and field of the DC shunt motor.

Through the 3φ full wave Controlled Rectifier, the 3φ AC supply converted to a DC voltage and provide to the armature and field of the DC motor, which flow in shape of T_A (Armature Current) through the ckt (DC motor) due to this controlled Dc the motor start in low speed.

If the DC motor start through ordinary way, then an external resistance is connected in the armature ckt, these resistors in armature ckt controlled the speed of the motor, (Gradually decreases the resistance form the armature ckt) and when total resistance (Resistors) remove form the armature ckt, the motor is rotate at its full speed (RPM). The main purpose of the resistance with the armature ckt is that, to match armature current with internal current (emf) to decreased value.

In case of the controlled rectifiers the resistors are not connected because at motor starting time the SCR connected in armature ckt set the delay angle value ,that the armature resistance controlled the voltage drop in the armature. The armature controlled method is mostly used as compare to the field controlled method,

In armature controlled method the field voltage is kept constant, while the armatures voltages changes.

In the given ckt rectifier converted to the in put DC supply (Full wave) , the rectifier is consistof SCRs , the out put of the SCR is Directly apply to the Armature in a variable shape. The applied voltage can be change form the changing the firing angle of the SCR.

Square A to Sine Wave Converter Wiring diagram Schematic

Build a Square A to Sine Wave Converter Circuit Diagram. This is a simple schema diagram in this schema using Two pairs of MOSFETs form a bridge that alternately switches current in opposite directions. Two parallel-resonant LC diagram complete the converter. The Ll/C1 combination is resonant at the fundamental frequency; the L2/C2 combination is resonant at the clock frequency`s third harmonic and acts as a trap.

Square A to Sine Wave Converter Circuit Diagram

Tl and C3 ensure that both halves of the MOSFET bridge are never on at the same time by providing a common delay to the gate drive of each half. Select the values of R1 and C3 to yield a time constant that`s less than 5% of the clock`s period. You can add an output amplifier for additional buffering and conditioning of the schema`s sine-wave output.

Monday, September 1, 2014

Medium Wave Modulator Wiring diagram Schematic

If you insist on using a valve radio and listening to medium-wave stations, you have a problem: the existing broadcasters have only a limited number of records. Here there’s only one remedy, which is to build your own medium-wave transmitter. After that, you can play your own CDs via the radio.

The transmitter frequency is stabilised using a 976-kHz ceramic resonator taken from a TV remote control unit. Fine tuning is provided by the trimmer capacitor. If there’s another station in the background, which will probably be weak, you can tune it to a heterodyne null, such as 981 kHz. As an operator of a medium-wave transmitter, that’s your obligation with respect to the frequency allocations. And that’s despite the fact that the range of the transmitter is quite modest. The small ferrite coil in the transmitter couples directly into the ferrite rod antenna in the radio.

Medium-Wave Modulator Circuit Diagram

Medium-Wave-Modulator-Circuit-Diagram

The modulator is designed as an emitter follower that modulates the supply voltage of the output amplifier. As the medium-wave band is still mono, the two input channels are merged. The potentiometer can be adjusted to obtain the least distortion and the best sound. The RF amplifier stage has intentionally been kept modest to prevent any undesired radiation. The quality of the output signal can also be checked using an oscilloscope. Clean amplitude modulation should be clearly visible.

The medium-wave modulator can simply be placed on top of the radio. A signal from a CD player or other source can be fed in via a cable. Now you have a new, strong station on the radio in the medium-wave band, which is distinguished by good sound quality and the fact that it always plays what you want to hear.

Author: Burkhard Kainka - Copyright: Elektor

Tuesday, August 26, 2014

Sine wave to square wave converter Wiring diagram Schematic

This is a simple Sine wave-to-square wave converter Circuit Diagram. Many signals are digitally generated or transmitted as square waves. It is often desirable to convert these signals into sine. In this Sine wave-to-square wave converter Circuit Diagram The sine input is ac coupled by capacitor C; Rl and R2 bias the input midway between Vn and Vp, the input threshold voltages to provide a square wave at the output.

Sine wave-to-square wave converter Circuit Diagram