Rene/Meissner EMF Higher Voltage Charger Variant

[forest]

I'm quite sure it could work continuously.... like similar circuit here https://www.youtube.com/watch?v=3Q6NA5N6ioU&feature=push-fr&attr_tag=rmh84E9sTase1VFw-6

[SkyWatcher123]

Hi all, Hi forest, thanks for sharing the video, i will study that later.

I could not get the dual transistor, npn pnp circuit to oscillate with the coil i have.
However, i know i can get the sucahyo oscillator to work and it has the advantage of the shortest on time possible, because it has the pnp backwards from the typical way.
I will see how it works with the rene split negative circuit variant.
peace love light

[SkyWatcher123]

Hi all, i was able to get the oscillator running i showed in post #27.

Im using 20 volt input at the moment, without the the led shown.

I'm testing different variables to see what effects what and added a resistor and capacitor in parallel on the PNP emitter leg.

Was able to get it oscillating by testing different transistors, using TIP3055 npn and TIP42 pnp, though a couple other combinations worked also.
peace love light

[SkyWatcher123]

Hi all, here is the circuit I'm testing at the moment.

It seems to be very efficient, both transistors run cool.
I did try with the voltage doubler off a 4 strand secondary, though this seems to perform better with the 2 parallel diodes.

Plus, it is using all 12 strands for the primary of the oscillator and lowering losses further.
Let me know what you think.
peace love light

[gyulasun]

Hi SkyWatcher,

This circuit must be tinkered with to make it oscillate when both transistors have a relatively low hFE values
like for the types you use. Even though their hFE values get multiplied in this Darlington connection
the resulting hFE may still be low and this is why the feedback components need the correct values
to start up oscillation. (2kOhm-100nF and 56kOhm-10nF). Especially that you use a 2 kOhm resistor
in the emitter which you found needed to reduce overall input current, its presence reduces the AC gain,
this is why a capacitor is needed in parallel with it. 
The voltage doubler is useful when the resulting supply voltage to the transistor and the primary coil is less
than the voltage of a battery to be charged as was the case for your last week circuit, this was the main reason
I suggested. (It is not good to pulse charge a battery with much higher voltage spikes than the actual battery voltage.)
I assume you find this circuit at least as efficient as the one you tested last week with the tv transistor?  To compare them,
similar input voltage and current values ought to be considered for both.
Good job, keep it up.

Gyula