SMD Transistors for RF use

I've decided to experiment with modern SMD transistors, to see if I can find a few that will work at least as well up to 30MHz as the old TO-39 2N2218 and 2N2219.  You can see the first episode on YouTube here:

Link to Video

I've attached below a link to a ZIP archive containing the three KiCAD files that I created for the simple amplifier circuit for evaluating various part numbers.  As I covered in the video, I had to create custom footprints for the SMDs to get better heat dissipation.  I am not including the KiCAD design for the TO-39 circuit.

Also included are the LTSpice simulations, minus several of the .lib files - the ones that specifically say that redistribution is not allowed are not included.  You'll have to go get them yourself.

For the input impedance model, I use an AC current source at 1A. Then measuring the output voltage is directly equivalent to the impedance (the units still say Volts but it also equals Ohms).

Enjoy!

Download File

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