lm317 adjustable power supply

lm317 adjustable power supply

   lm317 adjustable power supply is a easily built one.with a 12v 1 ampere transformer its capable of supplying  2v - 15v dc voltages.its enough for most of hobby projects.in here i have used half wave 12v transformer and result is quiet good.

circuit :

all diodes used here are 1n4007 D4 can be replaced by a 1 AMP schottky diode. if its hard to fine 4.7k pot replace it by a 5k or 6.8 k one.

PCB :

PDF

in action : youtube

Download eagle cad files :
https://github.com/stark9000/lm317_power_supply

java Swing Stop Watch

java Swing Stop Watch

 

java swing frame work is a great frame work when it comes to develop cross-platform software development.swing is actually a UI component library which support java platform.first came out bundled with Net-Beans IDE.which is a great Dev-environment for a some time and still to today.

   today i'm going to develop a java swing stop watch.which involves java Thread class so this software will be a multi threaded application. 

global variables and objects :

    private Thread TMR;
    private byte MIN = 0;
    private byte SEC = 0;
    private byte MSEC = 0;
    private volatile boolean RUNNING = true;
    private volatile boolean PAUSED = false;
    private Object PAUSELOCK = new Object(); 

timer start method :

 private void start_timer() {
        if (!jButton1.isEnabled()) {
            return;
        }
     
        jButton2.setEnabled(true);
        jButton3.setEnabled(true);

        reset_all();
        TMR = new Thread(() -> {

            jButton1.setEnabled(false);

            while (RUNNING) {

                synchronized (PAUSELOCK) {
                    if (!RUNNING) {
                        break;
                    }
                    if (PAUSED) {
                        try {
                            PAUSELOCK.wait();
                        } catch (InterruptedException ex) {
                            break;
                        }
                        if (!RUNNING) {
                            break;
                        }
                    }
                }

                MSEC++;
                if (MSEC == 100) {
                    jLabel5.setText(String.format("%02d", 0));
                } else {
                    jLabel5.setText(String.format("%02d", MSEC));
                }
             
                if (MSEC >= 100) {
                    MSEC = 0;
                    SEC++;
                    if (SEC == 60) {
                        jLabel2.setText(String.format("%02d", 0));
                    } else {
                        jLabel2.setText(String.format("%02d", SEC));
                    }

                    if (SEC >= 60) {
                        SEC = 0;
                        MIN++;
                        if (MIN == 60) {
                            jLabel1.setText(String.format("%02d", 0));
                        } else {
                            jLabel1.setText(String.format("%02d", MIN));
                        }

                        if (MIN >= 60) {
                            MSEC = 0;
                            SEC = 0;
                            MIN = 0;
                        }
                    }
                }

                try {
                    Thread.sleep(10);
                } catch (InterruptedException ex) {
                }
            }
        });
        TMR.start();
    }

timer pause method:

public void pause_timer() {
        PAUSED = true;
    }

timer resume method:

 public void resume_timer() {
        synchronized (PAUSELOCK) {
            PAUSED = false;
            PAUSELOCK.notify();
        }
    }

reset method:

 public void reset_all() {
        MSEC = 0;
        SEC = 0;
        MIN = 0;
        jLabel1.setText(String.format("%02d", 0));
        jLabel2.setText(String.format("%02d", 0));
        jLabel5.setText(String.format("%02d", 0));
        RUNNING = true;
        PAUSED = false;
        PAUSELOCK = new Object();

    }

timer stop method:

 public void stop_timer() {
        RUNNING = false;
        TMR.interrupt();
        reset_all();
        jButton1.setEnabled(true);
    }

in action  :youtube

download net beans project files : github