[AMPS] MRF150

[George K. Watson]

The EB104 kit is a design by a gentleman named Helge Grandberg of Motorola. He is a sort of
god for solid state amp designers. As far as solid state amps go, it is as good a performer as you will find.

Some advice:
Move lots of air over these devices.
Use a thick (3/8") copper heat spreader.
Use a big heat sink.
Build VSWR protection and overdrive protection in.
To cover the HF bands you will need 6 lowpass filters.

You may get close to half as rugged as your tube.

CC's splitters and combiners work FB.

To get a gallon out you will not need much drive with 8 MRF 150's in the EB104 configuration (2 modules,
4 MOSFETS apiece) , about 15 watts.

You will, however need 2.15 KW DC input at 50V, about 45Amps for good measure;) This is not easy to find.

In short, I believe that this project is a more difficult undertaking then most single device GG tube amplifiers. Even
with the EB104 supplies from CC, this is not a kit project. Of course it is a little less dangerous then building
a tube amplifier. You will wind a boatload more torroids, need more control and protection circuitry and have some
difficult layout problems to solve.

I run MRF150's for a gallon here and am working on the design for another amplifier using higher voltage MOSFETS,
so I am an SS believer.

(I also have a GG amp based on the GS-31b russian tube, 6m only)

Thanks and 73,
George K. Watson
K0IW

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