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PNP transistor or NPN transistor?

Eva713

Member
Good day, all
I'm kind of a newbie with electronics but I do know some how to differentiate the two. But in this there aren't any of the common markers. If I had to guess it would be NPN from NPN Transistor Arrangement and Symbol Basic but I can't be certain. If someone more experienced could help me out that would be great.

basic circuit.jpg

Also, if there are any guitar pedal guys out there, does the pot control the overall fuzziness of the circuit?
Any idea is appreciated. Thanks in advance.
 
The transistors should be NPN (you drew PNP). We usually use Q as the component designator; M is more commonly used for MOSFETs.

I'm not a guitar pedal person, so don't know what fuzziness means. The pot would control the frequency at which the gain is increased.

The capacitors on the right have their polarity reversed.
 
They did not draw the polarity of the 9V battery either, so it is possible to do this circuit with PNP if the top connects to the negative of the battery. That would explain the capacitor polarity too.

As DL324 says, that pot at lower right controls the increase at high frequency, which would be where it limits as square wave fuzz. That looks like an old circuit. 9V seems a little high for generating square waves these days, but maybe the more robust signals work better on stage.
 
Thank you all for the replies. Maybe I need to look up the data or measure the transistor for gain. One fact must be recognized that most transistors are made by many different manufacturers, and some transistors of one type have a different connection layout.
 
There are 3 standard pinouts for transistors in TO-92 (2N*, BC*, and 2S*); though there are some some exceptions (e.g. some BC have the same pinout as 2N).

Well designed circuits accommodate variations in transistor gain because it varies with current, CE voltage, and within and between manufacturing lots at the same manufacturer.
 
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