3v OU Flashlight

[TinselKoala]

what is the high voltage lines frequency in that area? 270Hz does not seem divisible by 50 evenly. I am not a high voltage Line man or engineer thus someone with knowledge in this area would be a help. Comments?

The ~270 Hz figure is calculated by Akula's scope and it also corresponds to reading the trace by eye and doing the math. But it could be a result of a harmonic of a slightly fluctuating mains frequency of about 50 Hz... maybe. Or the nearby CFL (if that's what it is) could be making some subharmonic of its oscillation frequency. I just can't tell unless I can duplicate the frequency as well as the general waveshape.

My circuit behaves like a very sensitive EM detector of sorts. I injected a 270 Hz positive squarewave pulsetrain at the inverter pin 13 input, using a FG, and got the following result. The squarish pulses are the "normal" output of the MC34063 and I think their width depends on the inductance of the coil half that is connected to the chip: less inductance, narrower pulses I think.

I'm working on another coil bobbin that will have inductances in the 30-60 microHenry range instead of the large milliHenry inductances I'm now using. Later this afternoon I should have some results from those.

[HG8AD]

TK said:

You might want to consider that the brass tube bobbin will act as a low ohmic shorted turn and soak up a lot of your switchers energy. It will need a vertical slot to avoid this. Best to use something non-metallic to avoid this and eddy losses.

(old switchmode designer)

I join the Vortex1 post   


According to me this the yellow brass tube, secondary coil,, short-circuit with   encumber the sign reduces the circle goodness of the transformer , PP and the lane   width....   

It will  need  a long  slot to 1mm width avoid  this 

,, yellow brass tube  to is ground wire,,


Excuse me for the bad English   

[starcruiser]

The ~270 Hz figure is calculated by Akula's scope and it also corresponds to reading the trace by eye and doing the math. But it could be a result of a harmonic of a slightly fluctuating mains frequency of about 50 Hz... maybe. Or the nearby CFL (if that's what it is) could be making some subharmonic of its oscillation frequency. I just can't tell unless I can duplicate the frequency as well as the general waveshape.

My circuit behaves like a very sensitive EM detector of sorts. I injected a 270 Hz positive squarewave pulsetrain at the inverter pin 13 input, using a FG, and got the following result. The squarish pulses are the "normal" output of the MC34063 and I think their width depends on the inductance of the coil half that is connected to the chip: less inductance, narrower pulses I think.

I'm working on another coil bobbin that will have inductances in the 30-60 microHenry range instead of the large milliHenry inductances I'm now using. Later this afternoon I should have some results from those.

Cool TK, looking forward to your results.

[d3x0r]

Yes, I know. Don't the specified foils in Akula's coils also have this effect? I think they are continuous wraps all the way around.

They're not; they are all gapped...


... much like the copper tube with a slit in several kapandaze gens

[TinselKoala]

Well, OK, I'll put a slot in the next ones then, but I think you are having a problem because my waveforms sure do look a lot like his, even without a slot.

Is anyone willing to predict an observable difference, with and without slot?  Because I have enough wire and brass tubing to make identical coils, one with and one without slot, for actual experimental comparison in this system ... something I'll bet you have never done. I'm not saying there is no effect, because obviously... I have not yet done the experiment. But I'll bet my next paycheck on this: the slot won't make the LEDs stay on after the power is removed.


Meanwhile, here's a short video where I try to explain the 'embedded sinus' waveform that appears and disappears in the MC34063 Pin 1 output signal.

http://www.youtube.com/watch?v=xBQwAlm-ryM

I switched the inductances around because the converter chip seems to like the larger inductance rather than the smaller one. In fact I should mention that I made a coil of about 600 microHenry and the chip didn't like it, drew 500 mA and heated up. But of course I didn't have a slot. Do you think that made a difference? I dunno. So I'm going to try 5.7 milliHenry next. With and without a slot.