Lasersaber strikes again. A joule thief king ?

[d3x0r]

I tried to replicate Lasersaber's SJRLooper but had little success.

Then I saw the video from Igor Moroz https://www.youtube.com/watch?v=P0kVuhWJwCY and this worked for me.

My transformer has three layers (no copper foil), first layer 29 turns, the a layer with 5 x 29 turns and finally a top layer with 26 turns, wire YT 0,6 mm.

I see a little feed back, but I have to try with a different transformer and a few LEDs (instead of the 220 V LED-Lamp).

I think that the diode in the feed back loop is not necessary because the battery withh absorb the negative pulse and store the positive pulse.

Greetings, Conrad

the foils are important, and lasersaber still has them wrong... see 3v akula circuit... which is what it's based on, other than a joule thief to drive it.

[conradelektro]

the foils are important, and lasersaber still has them wrong... see 3v akula circuit... which is what it's based on, other than a joule thief to drive it.

Please see the attached drawing. Which one is the right connection of the copper strips? Version B and C are probably the same.

Greetings, Conrad

[d3x0r]

Please see the attached drawing. Which one is the right connection of the copper strips? Version B and C are probably the same.

Greetings, Conrad

B and C are the same and B and C match this video


just flipped the coils so the dots were all on the same side in B  (made B last... C was a rough sketch)

[SkyWatcher123]

Hi folks, here is the circuit of my looper variant,
similar to what conrad posted.
It lights the 6 watt led bulb more than adequate
for a night light and using 3 AA nimh cells for 3.6 volts,
it gives very usable light at 200 milliamps or 720 milliwatts.
This gp19 ecosmart led bulb is non-modified.
Will be testing next with capacitor on input and see what we can do.

peace love light

[conradelektro]

Hi folks, here is the circuit of my looper variant,
similar to what conrad posted.
It lights the 6 watt led bulb more than adequate
for a night light and using 3 AA nimh cells for 3.6 volts,
it gives very usable light at 200 milliamps or 720 milliwatts.
This gp19 ecosmart led bulb is non-modified.
Will be testing next with capacitor on input and see what we can do.

@SkyWatcher: nice replication!

If you have time, you could try the changes I have indicated in your drawing. The power consumption should go down considerably. But the LED lamp will be a bit dimmer. (It might not work with 2.4 V, but it worked for me nicely with 3.6 V power supply.)

The 100 Ohm resistor is not very elegant and could be replaced by a better way of driving the transistor (which I have not figured out yet).

The LED from transistor base to negative rail consumes the negative spikes at the base which are not very good for the transistor (but the 1 K resitor at the base of the transistor might be sufficient to prevent damage).

Greetings, Conrad