Lasersaber strikes again. A joule thief king ?

[scratchrobot]

My take on Lasersabers circuit, running on a 100uf cap at 9v.
https://www.youtube.com/watch?v=nDP1XuUUZf8

[conradelektro]

My take on Lasersabers circuit, running on a 100uf cap at 9v.
https://www.youtube.com/watch?v=nDP1XuUUZf8

@scratchpot: I guess you used a MPSA18 transistor and the circuit as given here http://laserhacker.com/?p=410 ?

Trivial calculation for your circuit:

100 µF  *   9 V = 0.0009 As (charge at start Voltage)
-100 µF * 0.5 V = 0. 0.00005 As (charge at stop Voltage)
0.00085 As in 150 seconds (2 minutes 30 seconds) --> 0.00085 / 150 = 5.6 µA on average

Great achievement, congratulations. I saw the coil specs in your video info, thank you for specifying the details.

Greetings, Conrad

[scratchrobot]

@scratchpot: I guess you used a MPSA18 transistor and the circuit as given here http://laserhacker.com/?p=410 ?

Trivial calculation for your circuit:

100 µF  *   9 V = 0.0009 As (charge at start Voltage)
-100 µF * 0.5 V = 0. 0.00005 As (charge at stop Voltage)
0.00085 As in 150 seconds (2 minutes 30 seconds) --> 0.00085 / 150 = 5.6 µA on average

Great achievement, congratulations. I saw the coil specs in your video info, thank you for specifying the details.

Greetings, Conrad

Yes i used the mpsa18 and your calculations seem acurate
Thanks

[conradelektro]

Greetings Conrad

Tell me what inductance and ratio you would like me to simulate in each of the coils, maybe something similar to what LS is using. I already have a circuit that has a 1:1 ratio, 50 mH each, but it can be changed. See attached.

green =collector V
blue=baseV
red=LED current

@Vortex1: thank you for publishing your very interesting circuit. I am always impressed if something is done in a well documented way together with a simulation. I will come back to your nice circuit once I am done with LaserSaber's circuit.

If it is not too much work for you I would like to ask for the following:

Please simulate LaserSaber's circuit as given here: http://laserhacker.com/?p=410

- you could omit the three 1N4146 diodes if it is easier

- the MPSA18 would be important

- as coil please use my coil: see the attached drawing, the core is the following

http://at.farnell.com/ferroxcube/etd59-31-22-3c90/ferrite-core-half-etd59-3c90/dp/3056430?Ntt=3056430
FERROXCUBE - ETD59/31/22-3C90 -  FERRITE CORE, HALF, ETD59, 3C90
Farnell Order Code: 3056430
Manufacturer Code: ETD59/31/22-3C90

My goal:

- I want -30 Volt peak at the base, which windings ratio would achieve that (at 9 Volt supply Voltage)? (Now the ratio is 1:3 and the peak is about -15 Volt). In other words, the signal from the secondary should have an amplitude from -30 V to + 30 Volt (60 Volt peak to peak) at 9 V supply Voltage.

- What happens if I double the windings (while keeping the ratio) ? (I want more current in the signal, but the peak should stay at -30 V)

- I have enamelled wire with 2 mm diameter (31 Gauge) and 4 mm diameter (26 Gauge). If necessary I could get different wire.

So, my aim is to find windings which give me a peak of -30 Volt at the base (from the secondary) and a bit more current in the signal from the secondary as I have now (all at 9 Volt supply Voltage). I hope I specified the requirements well enough. I do not know how much current is in the signal now, but it seems a bit too weak.


My coil as it is now:

- now I have 29 turns (one layer) as a primary, 5.5 mH, the wire has 0.6 mm diameter but a very thick insulation, it has in total a diameter of 1 mm (the layer fills the whole width)

- now I have 145 turns (5 layers) as a secondary, 145 mH, same wire (1:5 ratio)


Planned new winding:

- 1 layer of 0.4 mm wire as primary (will have about 70 to 80 turns)

- 6 layers of 0.4 mm wire as secondary (will have about 420 to 480 turns) (1:6 ratio)

- a last layer of 0.4 mm wire which I can add in series to the secondary to get a 1:7 ratio

Could you simulate that (at 9 Volt supply Voltage)?  (I want to have a -30 V to +30 V and reasonably strong signal on the secondary)


Last question: I have to learn this simulation business, do you happen to know from where I can download a useful version of LTSpice (for Windows 7)?

Greetings, Conrad

[conradelektro]

Dark Alchemist's circuit meets with my approval.

DALM, using MPSA18 or BC337-25.

@TinselKoala: I know I could search for the DALM circuit, but do you have a link to the circuit or a drawing at hand?

What is the power requirement of your DALM inplementation (roughly)?

I saw the inductance measurement, thank you, that helps.

Greetings, Conrad