... Remember power = voltage x current so that at high voltages even a few milliamps can cause overheating....
Look at the circuit again - the NPN transistor's collector is always at high voltage whether its on or off - it can't saturate.
...just check the dissipation in that resistor...
We always used MPSA42 for NPNs and MPSA92 for PNPs for HV circuits like this. Cheap and In Stock at Digi-Key (among others) .
...Among those, here is a power supply which is using them.... I might have messed it up: I only get 90V, but I'll try again some time soon
I might start with 330K for R2 and 3K3 for R3.
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