Which transistor is best for joule thief between BC107 and BC547?

I want to make a joule thief to run led's from my death batteries.I have 2 transistors,BC547 AND BC107. Which transistor should I use to make a low voltage joule thief ?

-max-2 years ago

A germanium signal transistor might be what allows you to get down to insanly low voltages, since the junctions in standard transistors need about 0.6V just to conduct.

Crazynventor (author)  -max-2 years ago

Can u plz tell me which germanium transistors are best for very low voltage joule thief.

They are about the same the BC107 is 300 mW and the BC547 is 500 mW allowing a greater range of use.