wah buffer question

[starekase502]

im sorry if this has already been asked i really couldnt find it
but im wanting to replace the MPSA18 transistor in my 535q wah with a j201 and being a bit of a newb i noticed one is labeled emmiter base cathoide and the other drain grid source which terminal goes were thank you for your help

[anchovie]

Is this on the input or the output?

This schematic doesn't show a transistor buffer.

BTW, the pin names on a BJT transistor are collector/base/emitter and on a JFET are drain/gate/source.  The functional relationship is collector=drain/base=gate/emitter=source but without knowing whether you mean one of the transistors in the above diagram or another which is not shown it's impossible to say if a straight swap of the component will work or not.

[starekase502]

its for the input buffer someone on the forum maybe R.G recommended the swap

[anchovie]

Like I said, the schematic doesn't show a transistor input (or output) buffer. The first active part the signal hits is an op-amp and the transistors in that diagram are not buffers at all.

Did the mod that you read about specifically mention the 535Q or was it just referring to Crybabys in general?

[starekase502]

yes its for the 535q wah and there is a transistor buffer in my pedal mine is an early 535q that schematic is for a newer one the 535q was changed a few diffrent times they just never bothered changeing the name performed the mod today and it worked i just needed to know the pinout thanks for your help