3AX83B leg identification

[Richmondpedals]

Hi,

Just received some 3AX83B, but I cant figure out the collector base and emitter.  I also cant find a data sheet for them.

Can anyone help?

[LucifersTrip]

you can deduce that from this is you find out what Fuzz and layout THOMMO used...or just pm him.

http://www.diystompboxes.com/smfforum/index.php?topic=36392.msg902455#msg902455

[Richmondpedals]

Thanks, I will PM him

[jazbo8]

3AX83B，20V，0.5A，0.5W - like a larger version of the 81 AFAIK... So pin out should be the same as the 81.



Jaz

[Richmondpedals]

Thanks Jazbo8.  I could not find much info on them

[Mark Hammer]

If you have a meter that can test diodes, put it to that setting, and look for the relevant forward voltage reading between pins.  For instance, if it's a germanium PNP transistor, one should get a reading of somewhere between 180 and 300mv, with the negative probe on the base and the positive probe on either the emitter or collector.  If it's NPN, you'd get the same thing with the probes reversed.  If it's silicon bipolar, you should get readings between 500-600mv or so.

Once you have the base and type (NPN, PNP) identified, you can nail down which are the emitter and collector pins with your meter's hfe scale.  Insert the transistor in the relevant socket.  If you have the leads flipped around wrong, you won't get any hfe reading.  If you have them correctly oriented, you will get a reading that falls in a reasonable range - at least 90-100 for Si and at least 30 or so for Ge.

[jazbo8]

If you plan to work on many pedals (aren't we all ), then you should get a transistor tester, something like this DIY one works well for the purpose of identifying and showing basic transistor parameters.

Jaz