By : Eliza Sukiman
YB 0 BAJ Indonesian Amateur Radio Organization
This Mosfet Rf Amplifier will give you 800w output. The PA stage consists of four push-pull modules ,with splitter and combiner. each comprising a pair of IXYS 82N25P MOSFET devices. Each push pull is rated Po = 200W only. They have an "on resistance" of 0.35 Ohms , will dissipate about 500W each. V dss Drain Source Voltage 250 , Id Continuous Drain Current 82 A , C iss input Capacitance 4800pF,Output Capacitance 900pF .
produce 800w from 24V on 80 , 500w on 160 and 40 M .
The circuit work with four push-pull modules ,combiner and splitter The amp as shown needs 75W of drive for full output. The splitter wound on a small tubing or toroid transformer with about one turn pri. and two turns sec. The Combiner made from large ferrite tubes .
The Switching power supply is 24 Volts 100 A.
The standing current for this Amp.200ma for each mosfet.
Mosfet Rf Amplfier
Bias should be set to
about 400 ma by adjusting the 10k Ohm pot carefully! Remember these FETs can
really draw some current!,
Schematic
a pair of this schematic with splitter and combiner...
See Youtube 800w... Click Here