Kustom K25c-2

[g1]

No typo on the device, no typo on the schematic. Someone misread the schematic and installed 2N3657 where it calls for 2N3567.
Just someone using the wrong part.

[lowell]

I can't find any transistors with that #. Only Gen. Electric - Thyristor 2N3657 datasheet

[Enzo]

Lowell, 2N3567. Look by Q13 in your schematic. That is what they used, that is why Small Bear sells them.

2N3657 does not belong in the amp or in the schematic.

[lowell]

Agreed, thanks.

[g1]

Looking at that package in the link Lowell posted for the scr (true 2N3657) there is no way someone mistook it for a small signal transistor.
A real scr like that is one of those bolt on big guys.
Now I see why it may be a typo on the actual part he found in there, whatever it was. Strange.

[lowell]

Yes! Totally. Maybe a counterfeit.