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Buck Boost with 555

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Before spicing the booster I'm working on (with a 555 oscillator) I wanted to spice the simplest possible SMPS booster I could find: http://soundation.blogspot.com/2012/07/very-simple-5v-to-65v-dc-boost.html

I replaced the MOSFET with the MPSA42 I'm using, and the circuit seems to work in spice, switching at about 40 kHz and with an open-circuit output voltage a bit above 80 V. I'd like to breadboard it and need advice on a suitable PNP to use. Here's a plot of the voltages seen by the PNP:
**broken link removed**
Node 2 is the emitter, 1 is base and 5 is collector. Those Vbe spikes up to the full output voltage look a bit worrisome. Would a suitable high-voltage PNP BJT tolerate them?

Edit: this circuit has awful efficiency and is of no practical interest. Sorry for the noise.
 
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An mpsa92 is a complement for the mpsa42.
 
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