Enclosure not stated
Transistor Tester
Based on the Transistor Tester
From the post
Ever hear about "leaky" germanium transistor and wonder how to measure that? Well, here's a little utility board that allows you to test germanium transistors. It's based on this article by R. G. Keen, which you should definitely read. It explains pretty much everything going on in this process. I've included a switch to allow you to reverse the polarity of the power going to the board. This allows you to test both PNP and NPN transistors with the flip of a switch. The pads marked V and Com on the board are for your digital multimeter probes. Use pin headers here for easier use with your DMM probes, and be sure to use a socket for the transistor.
Schematic
This is a board layout, a drawing of where each part goes, and the post may link the schematic it was drawn from. Open the layout at Effects Layouts (blog). No KiCad fragment has been drawn for this circuit yet.
Parts list 4 rows
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| Ref | Value | Normalized | Type | Notes |
|---|---|---|---|---|
| Resistors 1 | ||||
| ×1 | 2.2M | 2.2M | read from the layout by eye | |
| Trimmers 1 | ||||
| ×1 | 5K | 5k | adjust to 2.472k; read from the layout by eye | |
| Switches 2 | ||||
| Gain | SPST | SPST | Sw1/Sw2 pads; read from the layout by eye | |
| Polarity | DPDT | DPDT | swaps +9v and ground for PNP/NPN; read from the layout by eye | |