On Thursday, November 1, 2012 11:56:39 AM UTC+8, jrehwin wrote: > > > I would like to make the Microcontroller flash the colon's in between > the Hour and Minute Numbers. > > (I will be later on using this for Temperature trends - fast flashing > for warming up and slow flahsing for cooling down) > > > > anyway I got some MPSA42's of the 'bay and wired them as following ==> > > > > http://www.halfluck.com/source/nixie/MPSA42.jpg > > > > Then uploaded the simple blink sketch to the Microcontroller. > > > > The issue I'm having is the Colon's just stay lit, they don;t actually > blink. > > You may have a weak pull-up enabled on your microcontroller, which leaves > the transistor on enough > to light the colon. If your microcontroller is an Arduino and you're > using pin 13, the LED on the Arduino > could be pulling your transistor on too. > > I'd suggest trying a different I/O pin. Another thing you can do if you > have an LED lying around is to > replace your 33k resistor with a 1k to 10k resistor and put your LED in > series. That way, the LED > should light when you're turning the transistor on. If you see the LED > flashing, that means you're > sending current into the transistor. If the colon still stays on, try > adding a resistor from the transistor > base to ground to absorb stray current. > > Other things you might want to investigate: does the colon stay on if you > power off the microcontroller? > If not, it means your transistor is okay, but your microcontroller isn't > turning that I/O pin off enough. > How about if you disconnect it from the transistor? If it still stays on, > you may have a bad or misconnected > transistor. > > - John >
Hello John, Fantastic Advice - Many Thanks. Yes it is an Arduino. I have it on Digital Pin 10 & had 13 Blinking too so I could see what was going on. That definitely gives me some ideas to work with. I will try all of your recommendations and report back. Cheers Rob. -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to [email protected]. To unsubscribe from this group, send email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msg/neonixie-l/-/qlOrsBZ27H8J. For more options, visit https://groups.google.com/groups/opt_out.
