Experience with "Caltech" Class E PAs?

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Experience with "Caltech" Class E PAs?

Postby Brian K1LI » Wed Apr 09, 2014 7:50 am

Dave Rutledge and his students at Caltech have published numerous articles on some very interesting Class E PA designs.

Does anyone have any experience with these units? Boards for the amps described in QST were available at one time, but no longer. I'd like to have the PCB artwork or some photos so I could produce one myself.

Thanks -- Brian K1LI
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Re: Experience with "Caltech" Class E PAs?

Postby Gilly » Fri Apr 11, 2014 11:42 pm

Hi Brian

Have never made the TX but could be a fun project.....

This here is a good read http://www.its.caltech.edu/~mmic/reshpubindex/papers/QST.pdf

The PCB would be easy to make up using a Dremel Tool or something similar......

The FET will get hot so a good Heatsink would be required....also a Variac controlling the Drain Voltage would be nice too.....

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Re: Experience with "Caltech" Class E PAs?

Postby kf1z » Sun Apr 20, 2014 12:32 pm

Actually, there was something pretty flawed in the caltech documents....

I can't remember what it was, but I remember possibly Steve, QIX commenting on that several years ago.
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Re: Experience with "Caltech" Class E PAs?

Postby Diego-CX4DI » Sun Apr 27, 2014 4:01 pm


I just experiment the Caltech Class E circuit in 7Mhz and 10Mhz some year ago and work very good as CW amplifier. Very recommended!

best 73's
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Re: Experience with "Caltech" Class E PAs?

Postby steve_qix » Thu Dec 31, 2015 9:07 pm

The main problem is a complete lack of headroom. Everything is run right to the edge.
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