I just wired up a PNP Germanium Tonebender. I had some problems wiring the DC jack but got it worked out eventually. What confuses me, however, is when I wired up the jack as you would for centre negative the circuit worked with a One Spot plugged straight in i.e. I wired up the +ve ground row to the negative of the DC jack and the -ve 9v row to the positive of the jack. And when I reversed the DC jack wiring and used a reverse polarity adapter, again the pedal worked.
What am I missing here? I would have thought that my first wiring of wiring the jack shouldn't have worked.
I wired up the circuit as per the below schematic, PNP, positive ground:
