Hi! If I want to build a PNP version of a circuit like the LPB1 or others simple boosters that usually use this transistor, do I have to do anything else apart of rotating the polarized caps and put a PNP transistor?
Also, what PNP transistor are good replacement for the common 2n5088 or 2n2222?
That would be very useful for 2 in 1 boxes with vintage germ fuzz + silicon booster.
Would a PNP germ transistor work for this modern boosters? That would be another option.
2n3906, 2n5087, mps6562, BC327 are all good Si pnp bjts. Ge will work also, with the usual caveats (leakage, temperature instability, etc.)
There are a couple of different ways to convert a circuit for pnps. If you're willing to use a battery or a dedicated (non-daisy-chained) adapter, then compare these two circuits and modify yours similarly.
If you want to use a daisy-chained adapter, then there are at least two common ways to modify the circuit, neither one is 100% successful for reasons only the gods understand. I usually recommend leaving the circuit as positive ground and building a dc inverter into the pedal.
In a circuit like the SHO, should I reverse the zener protection diode? I mean the one that protects the mosfet.
Yes. Assuming you're just building it with a standard positive ground like the PNP Fuzz Face schem, you can just flip the zener. If you build the version with two 1n4148 instead of the zener, you can just reverse those as well.