3v OU Flashlight

[Sergh]

http://en.wikipedia.org/wiki/Electrolytic_capacitor = http://www.youtube.com/watch?v=xpFMUPV1QOw

... e.t.c...
http://www.youtube.com/watch?v=mjkV4SYUwhQ

&

http://www.google.com/patents/US3434029

http://en.wikipedia.org/wiki/Fuel_cell + http://www.youtube.com/watch?v=JS1XclcWCe0

[MenofFather]

OK, now we are getting somewhere...

As usual, the secret was rather simple.
Everyone assumed that the switch coil (collector of C1815) was a single coil. Am I right guys?

From + and colector transistor is a single coil with two cuper not shorted tapes, conected to that coil. But maybe cuper tapes is not nessary.

[TinselKoala]

hi everyone,

I have attached screenshot of my back Emf produced by the 61 turns on 22AWG with copper shield with gap(gap align inside and outside during turning stage) on <3cm diameter pot core.This is my 1st winding attempt on small locally available pot core while waiting for 4.7cm diameter pot core.

Voltage 3.9volts(Li-ion)
current:6mA drawn for 5% duty cycle base on frequency 10hz.
Frequency applied:10hz....3khz produced same waveform as attached,no changes.Changes in waveform starts from 4.3khz onwards for my case.

The setup remains same using signal injected to base of C1815 transistor via 1k resistor.I'm also using 1000uf capacitor at emitter and (+) of my test circuit.

I got to head out.Time to work.

Can you try the exact same setup but with a different transistor like 2n2222a (metal can), 2n3904,  or some other similar NPN silicon type? I'm wondering how much of this behaviour is due to overdriving the transistor rather than some strange inductor behaviour.

Also, I'm losing track of the actual circuit you are using. Can you please show the _exact specific circuit_ you used to make the scopeshot, just for me? Thanks.
(I've looked through my stash of Japanese transistors-- I have hundreds of them-- but sadly not a single 2sc1815. Have you tried a higher-voltage transistor like 2sc1514? )

I read this in the 2sc1815 data sheet just under the AbsMax rating table, so it must be important:

Note: Using continuously under heavy loads (e.g. the application of high
temperature/current/voltage and the significant change in temperature, etc.) may cause this product to
decrease in the reliability significantly even if the operating conditions (i.e. operating
temperature/current/voltage, etc.) are within the absolute maximum ratings.
Please design the appropriate reliability upon reviewing the Toshiba Semiconductor Reliability Handbook
("Handling Precautions"/"Derating Concept and Methods") and individual reliability data (i.e. reliability test
report and estimated failure rate, etc).

[verpies]

I have attached screenshot of my back Emf produced by the 61 turns on 22AWG with copper shield with gap(gap align inside and outside during turning stage) on <3cm diameter pot core.This is my 1st winding attempt on small locally available pot core while waiting for 4.7cm diameter pot core.

The period between your pulses is approximately 400ns.  The Russian guy had 11µs.
Maybe with a larger core it will be longer.

What is the pk-pk voltage amplitude of the signal applied to the 1k resistor ?  Any DC offset ?

Voltage 3.9volts(Li-ion)
current:6mA drawn for 5% duty cycle base on frequency 10hz.
Frequency applied:10hz....3khz produced same waveform as attached,no changes.
The setup remains same using signal injected to base of C1815 transistor via 1k resistor.I'm also using 1000uf capacitor at emitter and (+) of my test circuit.

Like this ?

[magpwr]

Can you try the exact same setup but with a different transistor like 2n2222a (metal can), 2n3904,  or some other similar NPN silicon type? I'm wondering how much of this behaviour is due to overdriving the transistor rather than some strange inductor behaviour.

Also, I'm losing track of the actual circuit you are using. Can you please show the _exact specific circuit_ you used to make the scopeshot, just for me? Thanks.
(I've looked through my stash of Japanese transistors-- I have hundreds of them-- but sadly not a single 2sc1815. Have you tried a higher-voltage transistor like 2sc1514? )

I read this in the 2sc1815 data sheet just under the AbsMax rating table, so it must be important:

hi TinselKoala,

This is the hardest part to advise,base on what if component is altered.2N2222 plastic transistor is definitely the most popular transistor for any low voltage circuit.
I can try out the available 2N2222 transistor only tomorrow and advise,its kinda late now over here.

Since i am living in Asia access to Japanese transistors is easy ,C1815 already existed around 20years ago when i first came across this transistor.