On 25 January 2012 19:41, Kirk Wallace <[email protected]> wrote:
> On Wed, 2012-01-25 at 17:06 +0200, Viesturs Lācis wrote: > ... snip > > I tested by connecting/disconnecting 4N25 pin1 to GND and measured the > > voltage on laser power pins. > > Do you mean pin 2? Shorting pin 2 to ground should complete the circuit > and push current through the opto's LED. Place regular LED in series > with R1, just as shown for D?, but with an LED. The LED should light up > when pin 2 is grounded. If the LED lights up the opto's LED is sure to > light up too. > > > Conclusion - not working. I have 0V on output in both cases. Any > > ideas, what might be wrong? > > You can try a 12 light bulb in place of the laser to see if Q1 turns ON. > > > Can I short-wire +5V to pin4 of 4N25 to test, if it works then? > > Yes. 5 or 12 Volts to pin 4 should turn Q1 ON. Be sure R2 is in between > your short and Q1. If this works, replace U1, it might be defective. > > > That > > way I intend to check, if 4N25 is good or no. > > > > Viesturs > > See attached schematic. The . is hard to see so the "6 V" are really .6 > V. The voltages are approximate. > -- > > By the way, you are using a PNP package for a NPN device. Be sure to change it before doing a layout. Regards Roland ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
