BWJT

[kooler]

figure i would post some schematics of the backwards joule thief..

[conradelektro]

Thank you Kooler!

Great, I will make some test and measurements with your backward Joule Thief.

Could you please give an indication of the capacitor value and the tune-able resistor value you recommend?

In the circuit on the right (the one with the air core):

- I would put at least 40 turns on a 50 mm (2" inch) air core to come close to 100µH?

- And according to your teaching, there should be a third inductance between the collector (of the transistor) and the + pole (of the battery)?

I guess the three circuits are all for very low voltage batteries (0,5 Volt and even 0,25 Volt)?

Greetings, Conrad

[conradelektro]

Hi Robbie (Kooler)!

Because I am thinking about implementing your BJT and because I like air core coils, further questions concerning the circuit on the right side (the one with the air core):

The two windings 30 turns and 20 turns (air core), are they

- on two separate cores (two independent coils),

- bifilar,

- two windings one after the other on a single air core,

- wound (connected) in an counter-wound fashion?

Greetings, Conrad

[kooler]

the below pic is the same as above.. (i fix the diagram above also..)
it has 104k cap 100,000pf= 0.1 uf
10k resistor
mpsa06 transistor        amp draw = 7.8ma's at 0.9 volts

[kooler]

sorry but i fix the aircoil bjt .. this time it is right..