Sir TophamHatt Posted September 20, 2018 Share Posted September 20, 2018 Just to save a massive thanks to all those who have helped with the answers and food for thought on this. Tested today and it works pretty good! click here for Video I'll do a bit of a guide at some point in the near future about this. On a side note, not sure where the similar thread went but the stay alive will only make the motor go one way as reported in that thread. However, this is when using a Lais decoder. I don't have any others that I can use (tried with a Zimo but failed!). Thanks! Link to post Share on other sites More sharing options...
Nigelcliffe Posted September 20, 2018 Share Posted September 20, 2018 Just to save a massive thanks to all those who have helped with the answers and food for thought on this. Tested today and it works pretty good! Video: https://drive.google.com/open?id=1aQvSjIXXcEeCMgYndvlGg68mfDnbaTJl I'll do a bit of a guide at some point in the near future about this. On a side note, not sure where the similar thread went but the stay alive will only make the motor go one way as reported in that thread. However, this is when using a Lais decoder. I don't have any others that I can use (tried with a Zimo but failed!). Thanks! Its working, after a fashion, which is good. But its not working well, which could be due to the decoder being used. The video shows the motor stopping, then the capacitors do something to make it run again. Its as if the decoder is having a reset, deciding its not on DCC and working on DC instead. A properly working setup, on a decent decoder, won't show any interruption in running. Link to post Share on other sites More sharing options...
Sir TophamHatt Posted January 14, 2019 Share Posted January 14, 2019 Sorry for dragging this up again. It's been a while since I did this and now my extra notes have gone. Is this correct? So the black wire is the nagative and connects to the negative side of the cap. And then on the other side, the two positives meet from the last cap to the diode? And all that returns to the positive side of the chip? I'm sure it worked (I have a video!) but putting it in another loco seems to keep the lights on but not turn the motor. Thanks Link to post Share on other sites More sharing options...
Art Dent Posted January 14, 2019 Share Posted January 14, 2019 Sorry for dragging this up again. It's been a while since I did this and now my extra notes have gone. Is this correct? IMG_20190114_164156.jpg So the black wire is the nagative and connects to the negative side of the cap. And then on the other side, the two positives meet from the last cap to the diode? And all that returns to the positive side of the chip? I'm sure it worked (I have a video!) but putting it in another loco seems to keep the lights on but not turn the motor. Thanks Correct STH. In normal operation the diode is reverse-biased (this means no current will flow through it as its resistance in this direction is very high - much higher than the charging resistor) and so any current flows through the charging resistor into the stay-alive capacitors. The charging resistor (to limit the inrush current to the capacitor should be somewhere in the region of 50-100 ohms). When there is no track current, the capacitors discharge through the diode and ignore the resistor (since the resistance of the now forward-biased diode is much smaller than the charging resistor - for the popular 1N4007 diode this is around 0.9 ohms) - so the decoder sees a 'positive' supply on the blue wire and a negative (well negative with respect to the blue) on the black wire. This should - providing the capacitance is high enough - power the motor, lights and sound. If the capacitance is small, there won't be sufficient current flow to power the motor but any lights and/or sound should still operate as their power demand is much smaller. If you have just swapped the stay-alive to another loco and the stay-alive doesn't seem to be powering the motor - have you checked that the motor is still connected to the decoder? I'll PM you another possible reason (because I did it last night and it is too stupid to share on an open forum - I'd never live it down ) Hope this helps, Art Link to post Share on other sites More sharing options...
calvin Streeting Posted March 7, 2019 Share Posted March 7, 2019 thanks for info .. just made one a soldered to a Gaugemaster DCC27 see Link to post Share on other sites More sharing options...
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