Junkbox Voltage Negatizer (Vero)

[Toney]

 Chromespere's thread made me think about this. Just a simple oscillator/rectifier but it does the job.
Trannies can be whatever so long as Q2 is PNP.  3904/3906. 2n4401/3 for more power BD139/40, for more again. Whatever is in your junkbox.
Put voltage in one end - get negative voltage out the other, minus the diode drops so something like 2n5817 are excellent and if the diodes are ultra fast types that's very nice but anything works withing reason, so long as its ok with the current.
Puts out a reasonable amount of power >100mA with bc547.